2003 Grand Cherokee Laredo

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tjZ06

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What I have learned about the WJ so far: (no revelations but observations and confirming what others say...)

Ride is fantastic off road. I went from a 76 Cherokee to a Z71 Chevy Truck to a Tahoe to the WJ. The WJ is the most comfortable platform yet!
Flex is good stock, but disconnect front sway bar. The flex will increase even more dramatically, earn comments from the IFS guys, and reward you with a Cadillac ride off road. But, tire clearance amps to a whole new game when disconnected. A little rub when testing will be a major rub when in the rough. Bumpstop spacer length needs to be dailed in. To get the most out of the vehicle on road, after a lift definitely add the appropriate extended sway bar links and make sure geometry is in spec.

I really, really, really prefer the ride with the Rancho 5000x shocks over the Billsteins (which I thought were good). I can feel more with the Rancho, but it is not jarring or harsh, just better trail feedback so I know what is going on and less bottoming on the bumpstops. Doing 45 mph over washboard in Saline Valley made for a pleasant drive (but it killed the Billstein shocks). Install front bumpstop spacers, real ones, not the cheap boxed ones, when you install an upgraded track bar. Keep the bar off of the oil pan at full compression! Also, a 2x4 can be used as a replacement bumpstop spacer if you crush said cheap thin Amazon spacers doing 45 mph and hit an erosion ditch in the road.

Packing the WJ is a challenge, the cargo room and load capacity is limited. I had to get a backpacking mindset back. I do not feel much difference in handling with cargo on the roof (the Tahoe would sway noticeably). But mpg suffers. Coming home from the last trip, with gas cans on the roof and fighting the wind on highways 99 and 152, I was down 1 1/2 mpg. The cargo weight (max vehicle weight) of the WJ is limiting. Me and my co-pilot are big people, so we use up a bit of weight capacity. I took the electric seat frames out and installed manual, saving 20 pounds each. This allows me to carry my tool kit and a bit of recovery gear without going into the weight budget. With the rear seat bottoms removed, I lay out the soft toolbags across the floorboard and strap them in. Access is good and the weight is very low and centered in the vehicle. The axe and shovel fit under the folded down back seat top. With just a cooler and the tools/recovery gear, the ride is very neutral and the WJ ride is incredibly smooth. But a 7 day trip to Death Valley, with full load out and 2 people, put us just above max. With just me, I could do a 14 day trip and stay well below max weight.....

The hydraulic cooling fan makes me nervous. Temp bounces between 195 and 215+ seemingly at random. Strangely, temp drops if I run high range on long uphill grades and keep the RPMs down. I believe it is because the transmission temp increases enough to kick the fan into gear. With the 4.7, overtemp is a killer, so I would like some control of the cooling system. Underhood temps are always much higher then I like, the fan at idle does not push any airflow through the engine bay. The later model 3 wire solenoid is not adjustable so I have to live with the low fan idle rpm. I believe any constant airflow will help maintain a steady 195, and be that much easier on underhood components. For that reason a conversion to the 99-2000 electric/mechanical fan system is in the works. I will run the mechanical as primary and the electric fan to kick in at 200 degrees. I want the piece of mind I will not overheat this engine.

Why 3 1/2 inch lift? I chose this used WJ specifically for how it was optioned. It has full skids (i wanted the gas tank skid), Cardan joints (no Repezza), 242 transfer case, and Dana 44, V8 for me and a sunroof for the copilot. It will handle just below 4" lift withough needing to drop the transfer case, replace drivelines, install a slip yoke eliminator kit, and the like. At 4 inches things become marginal, and to do it right the expense goes way up. To the point where you might as well go 6". I am amazed at what I have done with the budget boost, and feel I will be able to do what I want without going extreme. 3 1/2 inch is the best value for the capability. And I will still be able to source many junk yard parts (like drivelines) if I need to get out of a jamb. Also, road manners will be fantastic. Going long arm in the front is just for luxury....and in case I want more later.

On this WJ, the two weakest points are the radiator and Dana 44HD aluminum housing. I will be adding a Goliath front skid to protect the radiator. The factory plastic bumper offers no protection. Any slip against a rock, a hit a stump while driving through grass or snow, it gets backed into, etc. will pop the radiator. A little steel in front will help that. The aluminum housing on the D44HD cannot be jacked up from the pumpkin, or it can deform and screw the ring and pinion setup. Same goes if you smack one of the axle tubes. Otherwise it is more than formidable for the platform. So in will go a truss and skid plate modified differential.

Lastly the gas tanks hang low. Even with just the budget boost, the only thing I have smacked on the trail is the gas tank when coming down a granite step. So a tank tuck is planned in the future.
I really enjoy your thread, and these insights - thanks for keeping the posts going! Some of my thoughts...

  • I know you're thinking about just the 3" IRO springs with a 1/2" spacer and their long arms, skids etc... but why not just go with the full 4" Rock Link kit (front Long Arm, rear stock arms) at that point? It's what I run and really, really, really like it so far. WJ 4" ROCK-LINK Long Arm Lift Kit - Iron Rock Off Road
  • You'll be able to run 32"s at 4" with some trimming (I know you've already seen what I've done), the ZJ washer (still haven't gotten around to installing mine, sorry - but I will do a write-up when I do), deleting the fogs, and maybe a c-hair more bump-stop AND/OR moving the axle forward a bit with the adjustable long arms (will require more trimming at the front of the front wheels, but so far I have done ZERO trimming rear of the front wheels and I got MINOR contact when hitting washes at high speed with my ~31.6"s)
  • I agree the WJs are great on road, and should be kept "road worthy" since they're so good at it. I think your plan will do just that. My grey one on the 4" actually drives better than the blue one on the 2" Budget Boost right now, IMHO. Part of that is because the entire front susp and steering is basically brand new and part of that is the Addco rear sway bar. It DOES clunk a bit more in the suspension with the solid "flex joints" on one end of the track bar and the suspension links. It's not anything you hear over music, but just something I thought I'd put out there... but the thing drives FANTASTIC.
  • I'm pretty surprised how much more you like the 5000x's over the Bilsteins, I might have to give those a try!
  • You've thought about your packing and load weight way more than I have... which is good. On my last trip w/ the WJ I had the entire back packed up to the bottom of the windows (with the rear seats folded) for just me, for 1 night. Obviously I had way too much shhhhhstuff. I believe my '03 Overland should have a 5,500lbs GVWR, and Curb weight is listed as ~4,081lbs where I've been able to find it. Payload seems to be listed at 1,000lbs... which seems right if the GVWR is 5,500... curb weight is ~4,300lbs for an Overland. Mine is a bit more w/ the lift, sliders, wheels/tires etc. so let's call it 4,500... leaving me that full 1k lbs to work with. I take a good chunk of that (keyword: chunk ;) ) but I'm still 110% confident I didn't go over 5,500lbs total.
  • I agree about the hydraulic fan. If you lose PS fluid, you lose cooling - that's bad news! I don't worry about the 195-215 fluctuation, had have yet to see it go above 215 so I'm okay with that, but the chance of failure just worries me a lot (like you pointed out, 4.7s don't love being over-heated). I'll be really interested to see how your '99/00 mech & e-fan swap goes. I have a good buddy that made me a super nice fan shroud for one of my sand rails, so I'm tempted to go pure electric on the fan situation with a high quality fan (or two) and a proper, custom-fab'ed shroud (plus a a good controller that properly modulates fan speed). It's just one of those "when I have time and can get it down to the fab guy" kind of things.
  • Agree on the radiator being exposed, when I do a front bumper I'll for sure be getting the radiator armor. I'm leaning towards this front bumper with the radiator protection: WJ Modular Front Bumper - Stubby Bumper and Outer Wings - Trail Forged They're kinda local so I at least can save on shipping.
  • 10000% agree about the darn gas tank. I need to get a rear bumper w/ tire carrier ASAP and do the tank-tuck as well.
  • Also agree on the D44HD. I'll probably truss mine up with a skid just like you did... but I'm always tempted to just go for gold and order the ECGS front and rear D44s...
-TJ
 

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I really enjoy your thread, and these insights - thanks for keeping the posts going! Some of my thoughts...

  • I know you're thinking about just the 3" IRO springs with a 1/2" spacer and their long arms, skids etc... but why not just go with the full 4" Rock Link kit (front Long Arm, rear stock arms) at that point? It's what I run and really, really, really like it so far. WJ 4" ROCK-LINK Long Arm Lift Kit - Iron Rock Off Road
  • You'll be able to run 32"s at 4" with some trimming (I know you've already seen what I've done), the ZJ washer (still haven't gotten around to installing mine, sorry - but I will do a write-up when I do), deleting the fogs, and maybe a c-hair more bump-stop AND/OR moving the axle forward a bit with the adjustable long arms (will require more trimming at the front of the front wheels, but so far I have done ZERO trimming rear of the front wheels and I got MINOR contact when hitting washes at high speed with my ~31.6"s)
  • I agree the WJs are great on road, and should be kept "road worthy" since they're so good at it. I think your plan will do just that. My grey one on the 4" actually drives better than the blue one on the 2" Budget Boost right now, IMHO. Part of that is because the entire front susp and steering is basically brand new and part of that is the Addco rear sway bar. It DOES clunk a bit more in the suspension with the solid "flex joints" on one end of the track bar and the suspension links. It's not anything you hear over music, but just something I thought I'd put out there... but the thing drives FANTASTIC.
  • I'm pretty surprised how much more you like the 5000x's over the Bilsteins, I might have to give those a try!
  • You've thought about your packing and load weight way more than I have... which is good. On my last trip w/ the WJ I had the entire back packed up to the bottom of the windows (with the rear seats folded) for just me, for 1 night. Obviously I had way too much shhhhhstuff. I believe my '03 Overland should have a 5,500lbs GVWR, and Curb weight is listed as ~4,081lbs where I've been able to find it. Payload seems to be listed at 1,000lbs... which seems right if the GVWR is 5,500... curb weight is ~4,300lbs for an Overland. Mine is a bit more w/ the lift, sliders, wheels/tires etc. so let's call it 4,500... leaving me that full 1k lbs to work with. I take a good chunk of that (keyword: chunk ;) ) but I'm still 110% confident I didn't go over 5,500lbs total.
  • I agree about the hydraulic fan. If you lose PS fluid, you lose cooling - that's bad news! I don't worry about the 195-215 fluctuation, had have yet to see it go above 215 so I'm okay with that, but the chance of failure just worries me a lot (like you pointed out, 4.7s don't love being over-heated). I'll be really interested to see how your '99/00 mech & e-fan swap goes. I have a good buddy that made me a super nice fan shroud for one of my sand rails, so I'm tempted to go pure electric on the fan situation with a high quality fan (or two) and a proper, custom-fab'ed shroud (plus a a good controller that properly modulates fan speed). It's just one of those "when I have time and can get it down to the fab guy" kind of things.
  • Agree on the radiator being exposed, when I do a front bumper I'll for sure be getting the radiator armor. I'm leaning towards this front bumper with the radiator protection: WJ Modular Front Bumper - Stubby Bumper and Outer Wings - Trail Forged They're kinda local so I at least can save on shipping.
  • 10000% agree about the darn gas tank. I need to get a rear bumper w/ tire carrier ASAP and do the tank-tuck as well.
  • Also agree on the D44HD. I'll probably truss mine up with a skid just like you did... but I'm always tempted to just go for gold and order the ECGS front and rear D44s...
-TJ
Thanks for your insight as well!
I am running good old fashioned U joints on the stock driveshafts, with the 242HD and slip yoke. If the stock drive system can reliably handle it without dropping the transfer case, then going right to 4" might be the best deal. I am lead to believe it is marginal for reliability, or at least hit or miss with the stock drivelines.
Updates will be a little slow with the holiday coming, but I'm slowly getting the parts for the cooling mod and bouncing some ideas around. The goal is to pay cash for Christmas and the mods so I'm not bogged down paying the card gods.
Some things I didn't mention:
The reason I go with snow rated tires- forget trying to get tire chains on a WJ with anything but the smallest stock tire size unless you want to shred a lot of stuff.
To help with breathing room in the rear wheel wells, and widen the stance a little, I will be going with cheap Wrangler steel 16's. The specs call for about an inch less offset than the stock Silverblades. 2" wider stance on the cheap appeals to my conservative nature.
Also I hatched a plan today for a little better front disconnect system.... the rear links on my Tahoe are 9" center to center (exactly what I want) and in the right configuration. I plan to pull one off and see what I see. I'm hoping it will work by just turning down my existing lower pins...and a new set costs under 30 bucks from Amazon. That will be a nice budget holiday project. Plan B is in reserve- customize a set of EVO Manufacturing links.
Lastly, I hope to acquire a stock rear sway bar from the pick and pull yard. I want to see if I can live with the highway manners to get even better flex back in the rear. When the previous owner did the budget boost, evidently the rear bar was upgraded. Maybe it will be something I switch in and out depending on the trip... who knows, but more stuff to play with to find the best balance. Even with the setup I have now, I know there is more capability to be wrung out. The devil's always in the details...
 

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Swapped out the stock Silverblade wheels for the Wrangled steelies. Offset is 1/2 inch less, giving me an inch wider track and breathing room for the rear shocks. The change is subtle.... and I like the no nonsense look.

Before and after pics of shock clearance:

P_20191227_103600.jpegP_20191227_133111.jpegP_20191227_133047.jpeg
 
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WJ Cooling Mod: WHY THE HYDRAULIC SYSTEM NEEDS TO GO

The hydraulic fan system was created to improve the 4.7’s heavy duty towing capability over the earlier electric and mechanical clutch fan combination. It is also said to be a pretty darn reliable system…..until it isn’t! If any part of the hydraulic system goes, you are stuck because you will lose cooling.

I’ve had power steering pump failures and blown hydraulic lines on other vehicles, but was always able to drive to home base for repair. With the WJ, good luck! The 4.7 is unlikely to survive a single overheating for a variety of issues. For example, years ago my parents lost their WJ due to a blown head gasket while freeway towing somewhere out in the Mojave Desert near State Line. And if the gasket would have held, likely a valve seat would have dropped very shortly after. The internet is full of stories like this (if you can believe the internet).

But what got me REALLY thinking is experiencing two undesirable behaviors in the hydraulic fan performance on my 03 WJ.

First, temperature drifts between 195 and 215 (deg F) seemingly randomly. On long gentle grades (think Saline Valley to Steel Pass with a full load out, tip toeing over and around rocks at slow speed and uphill for miles), it runs hot in 4 low and I get really nervous as it hits the topside of 215 and is still rising. I cannot get the fan to kick on to hold 195, even when triggering the computer by turning the AC on. To get the fan to kick on I have to shift to high range, drop the revs, and heat up the transmission. Once the transmission heats enough the fan comes on and quickly cools the engine back to 195.

Second, no air is moving at fan idle speed, the fan idles too slow. In traffic and at low speeds the coolant temp rises to 215 on and off even on a cool day. There is no way for me to speed up the fan idle speed to create airflow through the radiator and engine compartment. With no airflow, under hood temperatures are higher than they need to be and the engine compartment components see way more temperature than they need to see.

(Note: The early model 2 wire solenoid can be adjusted to increase fan speed, but is long obsolete and not reproduced. The later 3 wire solenoid does not have adjustability- and is what my WJ has).

It’s a shame- the cooling system capacity and hydraulic fan capability is there. With a couple tweaks to the control logic it would work very well. If the solenoid was adjustable, I could live with the system. But adding the fact the 4.7 engine cannot survive being over heated, there are multiple points of failure in the hydraulic system, and the cost and availability of parts is a serious issue, it’s time to abandon it and replace it with a more robust and controllable fan system.
 

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WJ Cooling Mod: PLANNING FOR A NEW FAN SYSTEM

I had a learning curve with warmed over muscle cars in my earlier years. The metal 4 blade fan would get replaced by a flex fan and 160 degree thermostat, then it would be necessary to add a pusher electric fan, and so on. Eventually I would always end up installing a factory hydraulic fan setup, stock or grafted in from a later model year. As a young gear head I learned two things quickly- cheap batteries are not worth it and turning your heater on max with a black vinyl interior and no AC is no fun in hot weather. The hydraulic fan, factory shroud, and a Modine 3 row Desert Cooler radiator was the ticket back then for worry free cooling.

I have also had very good experiences in low speed/high load conditions with hydraulic clutch fan factory setups. This includes driving off road in triple digit conditions in a number of vehicles, including but not limited to a 76 Blazer, 76 and 78 Jeep Cherokees, 99 and 03 Silverados, and the current 01 Tahoe. All have worry free cooling capability.

For the WJ I did not have to look far to find what I wanted for the fan system. The early model (99-01) 4.7 heavy duty cooling system has all the elements I want- a good fan shroud, a mechanical hydraulic fan, and an electric fan as a bonus. Good stuff!

Conversion to the early fan system is reasonably well documented on the net. The 99-01 shroud and 5 blade clutch fan assembly are bolt on. The power steering pump must be replaced to a standard pressure unit and the high pressure line must be replaced to the 99-01 hose. The return hose can be left alone and connected to the now oversized cooler. Disconnecting the hydraulic solenoid will cause an engine code, but a 10 ohm 100 watt resistor or leaving the solenoid connected satisfies the computer. The only loose end that remains is a controller must be integrated to control the electric fan. Success will be all about making sure the controller does what you need it to do.

Bingo! A trip to the Pick & Pull yard yielded in a 99 V8 WJ fan shroud and clutch fan assembly, fuse box wire and connector, and a few odds and ends. Out came the plastic and I started ordering the power steering pump, pressure line, and heck I’d be a fool to not replace the water pump and thermostat……..and the snowball began rolling.

I learned a lot about the parts subtleties and the early system operation protocols, and found I needed to tweak a few things. Everything stated above would work, but I know I can make it work better.
 

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WJ Cooling Mod: WORKING OUT THE DETAILS

The WJ 99-01 heavy duty system employs the computer controlled electric fan for primary cooling, and a 5 blade mechanical clutch fan for “help” when towing or otherwise stressing the system. If either fails, you can work around it and drive the vehicle some distance (outside temp and load dependent) before letting it cool.

But installing the system on the 02-04 WJ is not a slam dunk. There is no easy way to convert the hydraulic solenoid control to a PWM (speed controlled) fan controller (hello aftermarket?). And as said, I do not like the control logic anyhow. On the mechanical side, the 5 blade mechanical fan just doesn’t move enough air to make a go of it alone should when the electric fan fails.

Some folks delete the electric fan entirely, and install an 11 blade Ford fan. This provides more than enough cooling and is a simple, reliable fan system. My hesitation to do this is for three reasons- MPG may suffer, moving that much air all the time on dusty trails may make an unnecessary dust cloud at times when the clutch is fully engaged, and simply the fan noise may be insane.

Others do not use the 99-01 shroud, electric fan, and mechanical fan at all, and install a custom electric fan and shroud setup. In an effort to balance the system and not load the alternator much more than stock, and out of laziness of grafting in a fan shroud combo, this is not for me (another aftermarket opportunity is for a correctly sized, ready to go shroud system). For info on this pathway, MartinBuilt on YouTube has done an interesting mod using earlier Cherokee parts, and here at OB tjZ06 has a solid cooling mod being documented on his build thread “2003 Jeep Grand Cherokee Overland Build”.

To make the early system bow to my preference (with redundancy as well), I intend to swap the electric and mechanical fan duties. Upgrading the 5 blade mechanical fan to a 7 blade Jeep fan for primary cooling and adding a soft start-variable speed controller to use the electric fan as the “helper” if ever needed. All parts required to do this, with the exception of the fan controller, are 99 WJ or Jeep spec parts. For me this means parts availability is good (junkyard or chain parts store) and if I need a part I can send anyone to town to get it- or call ahead and know they have it. Just ask for a 99 WJ…… and the computer jockey at the counter can find it.

I have been working out the plan and been gathering parts since late summer. See notes for subtle particularities on why I chose to buy the part.
Time and budget kept me from going further. Behind the grill LED lights, front headlight support panel replacement, fog light delete, washer bottle relocation, fender trimming, and Goliath front skid plate will have to wait. Also my rear differential project is on hold as well until summer.

Most parts are in. Rip and tearing into the WJ is now dependent on a dry spell and a few free weekends. Doing this outside on a gravel driveway in the winter is unfortunately slowing me down (yeah, I’m getting old). But I will need to get it done and have some time to make sure it is all AOK before heading out to Utah this spring.

And yes, it was a slow week at work so I had way too much time on my hands to write this all up. But it was a good audit of my plan and parts so far.

cooling parts.JPG
 
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tjZ06

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Excellent posts, and so much of it mirrors my exact thoughts.

The stock hydraulic system has the capacity and is actually a pretty cool system -*BUT*- it's controlled using 20+ year old Chrysler computing and logic. I'm sure I could actually rig up my own solid state controller for the 3-wire solenoid, and that'd be a neat solution, but then you still have the drawbacks of any PS-system failure means a complete loss of cooling air as you pointed out. All-in-all heavy industry proves hydraulic fans CAN work... but in this application I don't see them as ideal.

To make the early system to my preference (with redundancy as well), I intend to swap the electric and mechanical fan duties. Upgrading the 5 blade mechanical fan to a 7 blade Jeep fan for primary cooling and adding a soft start-variable speed controller to use the electric fan as the “helper” if ever needed. All parts required to do this, with the exception of the fan controller, are 99 WJ or Jeep spec parts. For me this means parts availability is good (junkyard or chain parts store) and if I need a part I can send anyone to town to get it- or call ahead and know they have it. Just ask for a 99 WJ…… and the computer jockey at the counter can find it.
I really like this strategy! Some might say "but you're losing HP to the mechanical fan." Well, turning an alternator with additional electrical system load (e-fan primary system) or turning a PS pump with additional load (stock hydraulic system) also take power. And really, power isn't a big problem with our WJs. Even with my ~32"s and not re-gearing it's a pretty peppy machine and has no problem cruising at 85 MPH. If it were a 4.0L I6 in a rig with 37"+ tires, yes every HP counts. For us, I think it's a well chosen trade-off to give up a few HP for reliable cooling. Plus, how often are we really WOT in our WJs? Anytime we're not WOT there's always more HP available by dipping a little deeper into the throttle.



All-in-all I think you have a thoroughly thought-out plan and look forward to seeing it come together. BTW, if you get a case of the "well, since I'm in here"-s while you're at it and want to borrow any of the WJ-specific tools I bought to do the timing set, hydraulic lash adjusters etc. just let me know. Fingers-crossed I'll be done with that portion of things by the end of the weekend.

-TJ
 

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Thank you TJ! I'm trying hard to keep this contained to the cooling system, but may end up needing to borrow tools later in the year. As far as fan control, Dakota Digital has a nice controller that integrates with the computer, but I fear entering the world of Chrystler electronics. In my case the KISS principle is necessary so I can use what is left of my brainpower at work. Gainful employment is the sponsor of all this fun!
 

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Take the parts list in my "Working out the details post" with a bunch of grains of salt. As parts have arrived and I start to get a good look see, the parts list will change. First, the Intellitronx electric fan controller was poorly manufactured and will be returned (see "Rant to Vendors and Manufacturers" thread for details), not sure what to replace it with yet. Second, it does appear my AC high pressure line from the pump runs in front of the AC clutch, no fan will fit in there. I need to find and replace the high pressure hose from a non- hydraulic fan variant that runs above the AC clutch. Lastly, there are a lot of possible clutch/fan combinations out there. Ford based, Jeep based, GM based, Dodge.... I have my work cut out figuring out what will fit and work best for what I want.

Presently I have a junkyard 99 WJ fan clutch and 5 blade fan, and intended to find a 7 blade fan for it. Playing with parts, the 7 blade fan I found will not work, the blades are offset way too far back. Also it is 16" and the fan shroud is 20". The fan clutch is a heavy duty by spec for reference.

I also have the Ford parts, a Hayden 2794 clutch and 620-155 Dorman fan (18"). The net says this fits and works well, if not overkill. The clutch is severe duty, so I think it will be a nightmare in dust and MPG drop for no need.

A 3th setup I am considering is a Hayden 2621 clutch (standard duty) and a ZJ 7 b;ade fan (16.5").

A 4th setup that a few people have had success with is a Hayden 2736 Heavy Duty clutch with a Flex-A-Lite 6918 6 blade fan (18").

So it looks like I can't solve this on paper and just need to dig in, and be prepared to swap a few parts as it goes. To Be Continued......................



Edit Aug 3 2021-

Running modified stock fan clutch and 5 blade fan for some time now. Factory 5 blade fan moves plenty of air. It is all about the fan clutch engaging and ramping up the fan at the right time. There are no options for the fan clutch duty (std, heavy, severe duty) so we have to work with the one offered. To make a change tot he stock setting, bend the spring tab (lengthening the spring makes the fan engage at a lower temperature). A little goes a long way. (the alternate fans, such as the Ford setup, what you really get is the fan clutch that has a lower engagement temperature)

Second, the electric fan moves enough air to cool down the airstream hitting the clutch, fooling it to not engage. Back off the electric fan, trigger it high enough to be secondary and let the mechanical fan do the primary work. Temp stays a lot more consistent- just off of thermostat opening most times.
 
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IDK if this vid is sped up or if this guy huffs helium before he records, but nonetheless here's a 12-blade setup that fits in place of the stock 5-blade (so should work w/ the AC-line with a factory '99-01 shroud off a mechanical fan equipped 4.7).

-TJ
 
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IDK if this vid is sped up or if this guy huffs helium before he records, but nonetheless here's a 12-blade setup that fits in place of the stock 5-blade (so should work w/ the AC-line with a factory '99-01 shroud off a mechanical fan equipped 4.7).

-TJ
Thanks, I've seen this one. At the very beginning you can see his AC suction line is above the AC clutch. Mine runs in front. Also he has 2 mods to make the clutch and fan mate, with the combos I listed I can match that interface. Its about correct fan pitch to clutch rating and so on. I have multiple choices that will bolt up but will they work expectation? Say TJ, where are ya gonna put the fan controller? I was looking last night and don't see a spot. Hoping you are more creative than I.


P_20200121_103659.jpeg
 

tjZ06

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Thanks, I've seen this one. At the very beginning you can see his AC suction line is above the AC clutch. Mine runs in front. Also he has 2 mods to make the clutch and fan mate, with the combos I listed I can match that interface. Its about correct fan pitch to clutch rating and so on. I have multiple choices that will bolt up but will they work expectation? Say TJ, where are ya gonna put the fan controller? I was looking last night and don't see a spot. Hoping you are more creative than I.


View attachment 136464
Mine is in front like that, but there's still a LOT of room between the radiator and that line... a LOT. I do agree he had 2 mods to make and I'm not a huge fan of them for something spinning on the front of your engine. He had to drill-out the fan holes and grind the locating tabs on the fan clutch. He did mention a different fan clutch that somebody else had used which didn't require that.

As for the fan controller, it's mounted on the fan shroud straight from Derale:

fancontroller2.jpg
fancontroller1.jpg



I know you have a lot of time and thought invested in your setup, but I hope to have this thing back together next weekend so just a thought, if you're not rushed maybe wait to see how mine works out? I bet you could return a lot of parts and pay for some of the (expensive-ish) Derale unit.

-TJ
 
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JimBill

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Mine is in front like that, but there's still a LOT of room between the radiator and that line... a LOT. I do agree he had 2 mods to make and I'm not a huge fan of them for something spinning on the front of your engine. He had to drill-out the fan holes and grind the locating tabs on the fan clutch. He did mention a different fan clutch that somebody else had used which didn't require that.

As for the fan controller, it's mounted on the fan shroud straight from Derale:

View attachment 136466
View attachment 136467



I know you have a lot of time and thought invested in your setup, but I hope to have this thing back together next weekend so just a thought, if you're not rushed maybe wait to see how mine works out? I bet you could return a lot of parts and pay for some of the (expensive-ish) Derale unit.

-TJ
Yes, I have the time and am watching your progress! When you are done ill probably hit you up to come see it.

I have a path forward for the AC line, if I can find one at the junkyard in the right shape my ex brother in law will freshen it up- use the ends and crimp on new hose. (Ran into him at lunch today, by luck).

I have enough clutches and fans to get started and work, just maybe not optimized.

If your Derale controller works well, ill go with the same, just need to find a spot for it. Or go with the Dakota Digital and mount it in the glove box. TBD!
 

tjZ06

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JimBill - just some thoughts on things to do "while you're there" doing the cooling system job, and a couple lessons-learned:

  • If you have no valve-train clatter I wouldn't dig into the hydraulic lash adjusters, necessarily - but they aren't really too bad if you have the valve covers off and quality parts are cheap
  • I HIGHLY doubt you need to do a timing set like I did unless you're well past 200k miles, I could hardly catch a finger nail in the grooves on the guides and there was no discernible slop in the chains or really even recognizable wear in the sprockets
  • I WOULD absolutely plan to do the re-seal. I really didn't think I had leaks, because none of them were bad enough to cause a nasty engine bay, burning-oil smells, or a mess on the ground. I really thought I had basically no leaks on this thing before I got started. In truth, the front cover seal was leaking. Both valve covers were leaking. And the worst leak was probably the PCV hoses at the back of the cylinder heads
  • Some stuff is obvious to get, like a new water pump and new PS pump since you need a '99 unit. However there are a few things that I didn't think to order. The plug for the driver's side cylinder head is one good example (Mopar 53021031), the upper "donut" mounts (Mopar #52079419) for the radiator is another. I had ordered the lower isolators (Mopar 52079884AA), but forgot the uppers.
  • You also might as well get a PCV valve and a section of line for where it connects, mine was super brittle and the line was very cracked (moreso than any other lines in the whole engine bay)
  • If you ever had a bad/leaky batter just order a battery tray and the hardware associated with it. You can just replaced the little J-clip as the plastic itself doesn't seem to break down, but I just got a tray
    • Plan to clean/paint under the battery area if it had ever leaked
  • Plan on doing your heater hoses, and I really recommend swapping to full soft-line like I did. Let me know ASAP if you decide to keep the AL hard-lines, I have all 4 molded soft lines to work with them I didn't use, I'll send 'em your way for 50% of cost. Just be aware you'll need to use a traditional hose-clamp to secure them to the hard-lines unless you want to order complete units with the soft-lines pre-crimped to the hard-lines... but they run ~$125 each and hardly seemed worth it to me. I prefer that I can easily service the soft-lines on the trail, and I ran them more out of the way for future services (plugs and such). Unless you have very long, very skinny arms plan on getting some cable-operated hose-clamp-pliers to get the clamps at the firewall.
  • I also ended up with lots of extra stuff (some of which I'll be able to return) because I wasn't meticulous with my ordering. For example, I ordered a new radiator cap, but the new radiator included one. I ordered a water pump gasket, but BOTH the new water pump AND the front-cover seal sets had water pump gaskets. I ended up with multiple lower radiator isolators because I ordered them way early in the process, forgot I had ordered them, so re-ordered when I made a follow-up purchase. I ordered a new battery temp sensor, but the new battery tray included it. I actually forgot to order the gasket for the oil-filler neck... but the front-cover set had it.
  • If you haven't already re-done you exhaust manifold gaskets and bolts, definitely plan to do them while access is better. I had actually already done mine.

I'll let you know if I think of any other tips...

-TJ
 

JimBill

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JimBill - just some thoughts on things to do "while you're there" doing the cooling system job, and a couple lessons-learned:

  • If you have no valve-train clatter I wouldn't dig into the hydraulic lash adjusters, necessarily - but they aren't really too bad if you have the valve covers off and quality parts are cheap
  • I HIGHLY doubt you need to do a timing set like I did unless you're well past 200k miles, I could hardly catch a finger nail in the grooves on the guides and there was no discernible slop in the chains or really even recognizable wear in the sprockets
  • I WOULD absolutely plan to do the re-seal. I really didn't think I had leaks, because none of them were bad enough to cause a nasty engine bay, burning-oil smells, or a mess on the ground. I really thought I had basically no leaks on this thing before I got started. In truth, the front cover seal was leaking. Both valve covers were leaking. And the worst leak was probably the PCV hoses at the back of the cylinder heads
  • Some stuff is obvious to get, like a new water pump and new PS pump since you need a '99 unit. However there are a few things that I didn't think to order. The plug for the driver's side cylinder head is one good example (Mopar 53021031), the upper "donut" mounts (Mopar #52079419) for the radiator is another. I had ordered the lower isolators (Mopar 52079884AA), but forgot the uppers.
  • You also might as well get a PCV valve and a section of line for where it connects, mine was super brittle and the line was very cracked (moreso than any other lines in the whole engine bay)
  • If you ever had a bad/leaky batter just order a battery tray and the hardware associated with it. You can just replaced the little J-clip as the plastic itself doesn't seem to break down, but I just got a tray
    • Plan to clean/paint under the battery area if it had ever leaked
  • Plan on doing your heater hoses, and I really recommend swapping to full soft-line like I did. Let me know ASAP if you decide to keep the AL hard-lines, I have all 4 molded soft lines to work with them I didn't use, I'll send 'em your way for 50% of cost. Just be aware you'll need to use a traditional hose-clamp to secure them to the hard-lines unless you want to order complete units with the soft-lines pre-crimped to the hard-lines... but they run ~$125 each and hardly seemed worth it to me. I prefer that I can easily service the soft-lines on the trail, and I ran them more out of the way for future services (plugs and such). Unless you have very long, very skinny arms plan on getting some cable-operated hose-clamp-pliers to get the clamps at the firewall.
  • I also ended up with lots of extra stuff (some of which I'll be able to return) because I wasn't meticulous with my ordering. For example, I ordered a new radiator cap, but the new radiator included one. I ordered a water pump gasket, but BOTH the new water pump AND the front-cover seal sets had water pump gaskets. I ended up with multiple lower radiator isolators because I ordered them way early in the process, forgot I had ordered them, so re-ordered when I made a follow-up purchase. I ordered a new battery temp sensor, but the new battery tray included it. I actually forgot to order the gasket for the oil-filler neck... but the front-cover set had it.
  • If you haven't already re-done you exhaust manifold gaskets and bolts, definitely plan to do them while access is better. I had actually already done mine.

I'll let you know if I think of any other tips...

-TJ
TJ,

There is nothing more valuable than first hand advice from a trustworthy source. Thank you.
After I've had time to let it settle between the ears I'll shoot you a message (so I don't Bogart this thread with just thoughts).

James
 

tjZ06

Rank V
Launch Member

Advocate I

2,268
Las Vegas/Palo Alto
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mynameisntallowed
Last Name
Adams
Member #

20043

TJ,

There is nothing more valuable than first hand advice from a trustworthy source. Thank you.
After I've had time to let it settle between the ears I'll shoot you a message (so I don't Bogart this thread with just thoughts).

James
Sounds good... oh, also spark plugs. As you saw in my thread mine were well over-due.

-TJ