2003 Grand Cherokee Laredo

[Ronald Miranda]

Thanks for your comments! I did go back to the Bilsteins, I kept blowing the right front Rancho. Likely I was a little off on my lengths and I think I kept bottoming the shock out. Letting them ride for now other than need to install bar pin eliminators to the front shocks. And they are a little short for the new lift now. We shall see how the springs settle in and do under load. Keeping the OME springs in case I find the IRO too soft. In the meantime chasing vibration from either front or back driveshaft and normal other tinkering such as caster/pinion angle compromising and other tinkering.

On cooling so far so good, but I do want to add hood vents soon. Hopefully a patriot blue WJ shows up in the local pick and pull with a decent hood to cut up. I'm a little wary of cutting my original and would like to experiment/dial it in on a donor. The only time het rose uncomfortably was when I held it on a steep hill by throttle instead of the brakes on a 105 edgree day. Self induced. Shows I need a bigger transmission cooler someday. Just backed to level ground and let it idle in park and it came back to norm.

I do have a 185 thermostat but have not put it in. one of these days will need to try that as well.

Well, great choice going back to Bilstein, I just love it!.
IRO is kinda soft. Those are 190 F/185 R LB/IN. OME is way better with the load (over 220lb/in).

I've never considered the bar pin eliminator, I will check it out.
FYI. I used the hood vents from a Mustang GT, and absolutely love it! Check those, maybe you'll like them.

I've built more than 4 WJs.
I'm building another one, for my brother-in-law. But we always go 4" or more. With the RC Add On long arms, Bilsteins, and Clayton 4.5". The RC will drop the T-case and includes the Skid Plate, so, no major worries.

I will keep your post, and any info you may have. Just hit me up!

 

[JimBill]

Hmmm, I didn't realize anything but the full QD system had a rear VL, you learn something every day. I probably used the same sync with the modifier you do, lol (IIRC it was redline) but found they like a little of the Mopar stuff too. And I agree, if it doesn't get driven it gets grumpy. As for the Cs the guy that did mine (and built the exhaust for the Hemi swap) would certainly do yours too (yours should be far easier since there is less truss/custom shock mounts/bump pads/etc. going on) - want me to check on a ballpark price?

-TJ

Yes sir! Ballpark price and availability. If the price is within budget I may have the one on the vehicle done first . Then I won't worry about it anymore! PS I edited in an earlier post a photo of the D44A when open. Cleanest I have ever seen, a testament to your maintenance. Many will say rotating the Cs at 3" lift is a waste of money. Fair enough, for each his own. And if I ever go higher I'm good to go.

 

[tjZ06]

Yes sir! Ballpark price and availability. If the price is within budget I may have the one on the vehicle done first . Then I won't worry about it anymore! PS I edited in an earlier post a photo of the D44A when open. Cleanest I have ever seen, a testament to your maintenance. Many will say rotating the Cs at 3" lift is a waste of money. Fair enough, for each his own. And if I ever go higher I'm good to go.

I'll look into it! And you know me well enough to know I won't be the person saying rotating Cs at 3" is a waste. I think I lucked out with my WJ at 4" where I had no driveline vibrations at all, and still had reasonable caster and it drove at least as good as stock, perhaps better (the better part is probably because I upgraded the rear sway bar, did new Bilstein 5100s, etc. with the lift). Like you said, the great thing is you can have them rotated enough for a 6-7" lift later, but set it for a good caster number now and have an amazing front driveshaft angle. I did see you mentioned how clean it was in the diff... honestly it wasn't just *my* maintenance. I bought it at ~92k and I think the axles came out at around 112k. The original owners were as over-the-top as me, but all dealership maintenance and all way ahead of schedule. I hope those axles serve you well!

-TJ

 

[tjZ06]

Well, great choice going back to Bilstein, I just love it!.
IRO is kinda soft. Those are 190 F/185 R LB/IN. OME is way better with the load (over 220lb/in).

I've never considered the bar pin eliminator, I will check it out.
FYI. I used the hood vents from a Mustang GT, and absolutely love it! Check those, maybe you'll like them.

I've built more than 4 WJs.
I'm building another one, for my brother-in-law. But we always go 4" or more. With the RC Add On long arms, Bilsteins, and Clayton 4.5". The RC will drop the T-case and includes the Skid Plate, so, no major worries.

I will keep your post, and any info you may have. Just hit me up!

I had the bar-pin eliminators when I was a 4" long arm and much more "stock" style suspension. I'd do it again on another WJ, for sure.

As far as hood vents: 2003 Jeep Grand Cherokee Overland Build I wrote a good bit about the hood vents. 99% you see done are in the wrong place. It's very hard to get the vents in the right place on a WJ, but I feel I did as close to "correct" as I could. The short version is the middle of the hood where everybody puts them (assuming "well you want the heat coming up off the engine to come out the vents) is absolutely the wrong place. They need to be above the void between the cooling stack and the front of the engine.

-TJ

 

[JimBill]

Last few evenings ran the tape measure and angle finder all around. Where 3 3/4 lift put things:
Axles are exactly parallel per tape measure resolution.
Corner to corner on axles compares to within 1/8 inch. Square enough.
Transfer case and rear pinion angle within a 1/4 degree of each other. Dead on by my standards. Need to add 1 degree to account for any axle rotation under full torque. No biggie.
Rear driveline u joints both operating at 8 degrees. Should be ok.
Steering linkage at 6.5 degrees and track bar at 9 degrees for a 2.5 degree delta. So it goes, should be ok for now and fab work would be required to get both truly parallel.
Here is where the numbers say there is definitely a problem. Front pinion angle at 4 degrees, driveline at 8.9 degrees, for a 4.9 u joint angle. Has the double Cardan at transfer case so pinion joint needs to be as close to zero as you can get.
Caster, as I could measure it off the top u joint flat is about 6 degrees (not sure I believe it).
So that leaves me now playing the game. If my numbers hold true, with proper adjustments I can get near zero front u joint angle but approach 1 degree of caster. Not so good.
Next Fri will try and get a real reading from an alignment shop and see if my caster is where I think it is.
Then will adjust the uppers and split the difference. And see if that calms the vibes down.

Did get spark plugs changed today, they were a little overdue.

Yup, at 3 3/4 lift rotating the Cs is not overkill and feasibly necessary. Depends what compromises one is willing to make.

In my case the WJ needs to fly down the Hwy at 85 mph with my lady driving, and then crawl in 4 low over obstacles for me.

So tinker tinker tinker!

 

[Ronald Miranda]

I had the bar-pin eliminators when I was a 4" long arm and much more "stock" style suspension. I'd do it again on another WJ, for sure.

As far as hood vents: 2003 Jeep Grand Cherokee Overland Build I wrote a good bit about the hood vents. 99% you see done are in the wrong place. It's very hard to get the vents in the right place on a WJ, but I feel I did as close to "correct" as I could. The short version is the middle of the hood where everybody puts them (assuming "Well you want the heat coming up off the engine to come out the vents) is absolutely the wrong place. They need to be above the void between the cooling stack and the front of the engine.

-TJ

Thanks, man, I will order the BPE ASAP.

About the hood vents (just read your post, I install them right in the position you had them. (The big ones) The main problem I saw was the Alternator, it was just below the left hood vent.
I fabricate an alternate cover for it, so I can protect it from heavy rain. Works just fine now.

I will measure with a temp gun, how many degrees you can lower your engine bay with them. comparing to my brother-in-law WJ. And I will let you guys know.

 

[tjZ06]

Last few evenings ran the tape measure and angle finder all around. Where 3 3/4 lift put things:
Axles are exactly parallel per tape measure resolution.
Corner to corner on axles compares to within 1/8 inch. Square enough.
Transfer case and rear pinion angle within a 1/4 degree of each other. Dead on by my standards. Need to add 1 degree to account for any axle rotation under full torque. No biggie.
Rear driveline u joints both operating at 8 degrees. Should be ok.
Steering linkage at 6.5 degrees and track bar at 9 degrees for a 2.5 degree delta. So it goes, should be ok for now and fab work would be required to get both truly parallel.
Here is where the numbers say there is definitely a problem. Front pinion angle at 4 degrees, driveline at 8.9 degrees, for a 4.9 u joint angle. Has the double Cardan at transfer case so pinion joint needs to be as close to zero as you can get.
Caster, as I could measure it off the top u joint flat is about 6 degrees (not sure I believe it).
So that leaves me now playing the game. If my numbers hold true, with proper adjustments I can get near zero front u joint angle but approach 1 degree of caster. Not so good.
Next Fri will try and get a real reading from an alignment shop and see if my caster is where I think it is.
Then will adjust the uppers and split the difference. And see if that calms the vibes down.

Did get spark plugs changed today, they were a little overdue.

Yup, at 3 3/4 lift rotating the Cs is not overkill and feasibly necessary. Depends what compromises one is willing to make.

In my case the WJ needs to fly down the Hwy at 85 mph with my lady driving, and then crawl in 4 low over obstacles for me.

So tinker tinker tinker!

I really appreciate your thorough process and write-up! I wish I had measured everything when mine was still on the 4" IRO Rock-Link kit. I don't know how, but it drove absolutely stelar, had no driveline vibrations, and was just an excellent setup (so of course I had to rip it all of and change it, lol). Once I had the very custom Trail Forged setup done, which is around a 7" lift as best I can figure measuring against other WJs, I had a nightmare on my hands. To get the pinion angle in the realm of acceptable the front end had 0, or perhaps even a degree of negative caster - no bueno. As you know cutting and rotating the Cs was my solution so we could get the pinion/driveline dead-nuts and have 7 or 8 degrees of caster in it (more than the "spec", but with the hydraulic assist steering I prefer the extra to improve higher speed road manners with really no downside for trail maneuverability w/ the hydro). I'm still a bit surprised you ended up needing to rotate the Cs, but I fully agree with your math. I wonder if I just had atrocious front driveline angles? Then again, at that point I still had the 247 t-case in it, so not only was spinning the front driveshaft at all times like all WJs, it was also *powering* the front driveline at all times. I think if my angles were terrible it would have manifested as vibrations, and the thing seriously had NONE. Like I said, I don't recall what I had for caster at that point, but I know it drove wonderful so it had to be at least 4, I'd guess...

BTW, my guy says prob early next year to be able to get you in for the C rotation. IDK if that's a non-starter for you, but it seems like EVERYONE is backed up 6+ months these days. With what's happening in our economy I'm surprised how many builds are still going on right now.

-TJ

 

[JimBill]

BTW, my guy says prob early next year to be able to get you in for the C rotation. IDK if that's a non-starter for you, but it seems like EVERYONE is backed up 6+ months these days. With what's happening in our economy I'm surprised how many builds are still going on right now.

-TJ

Thanks TJ. Just my aerospace engineering mind, or more likely preemptive laziness. Easier to figure out how to get where I am going when i know where I started.
Early next year is AOK, good timing to have him rotate the C's on the front Varilock diff hand me down from your Overland. Just do it once and roll it into that project. Good time to replace ball joints for the hell of it as well.
By then I will know exactly where I want things to be. Some relationships that are minor but are unaccounted for-such as the driveline angle will change slightly as the pinion is rotated up- actually helping the numbers a wee bit. Have not done the math based on driveline length, and so on, so will just do it and let the angle finder tell me what it ends up. For now I will just tinker and see where I can get.
The far worse case is to drop it back down to an even 3 inch lift with the OME springs I am holding on to, until such time the Cs are rotated and the diff is installed. I may find the happy medium without rotating the Cs, but I hate compromises so that will not change my desire to have the Cs done on the donor front diff early next year.
A deadline came up for an adventure up by and around Leviathan Peak, giving me only this coming weekend to find the sweet spot. Also this weekend I need to go to Hollister Hills and flex it out and see just how bad the tire clearances are lol.
And with shipping so erratic, don't think I can squeeze a steering box replacement in time. Kinda feel like I am in a reality TV show with self- induced timelines to make it interesting......
I was going to send you the factory hub to fender measurements so you can measure what your lift is over "stock", but no, you modified the fender openings so that ain't gonna work!!!!!!

Strange as you mention, this "discretionary" spending segment hasn't slowed yet. It is VERY interesting times for sure.

 

[JimBill]

The numbers are in and don't lie. 5 degree front u-joint angle told me that is the likely problem for all the vibration.

Last night I adjusted the front upper arms almost a half inch out to get a clean front u-joint angle. Yup, vibration under load now gone. Well that big vibe anyhow! Also, I had speculated (at 3 3/4 lift) that a properly aligned pinion angle will force caster towards zero.

The results are in! Got it on the alignment rack today. With a .75 degree front u-joint angle, (was aiming for 1 degree) caster is 1.3 degrees. Other things learned at the rack- toe was off pretty good and was set to minimum spec per my request. Also, the donor rear diff is CONSIDERABLY straighter than the one that came out. Lastly, I got lucky and set this up pretty dam square.

I failed to measure front u-joint angle with the budget boost before all this. I know it was not ideal, but it had no vibes. I do think I can start easing the front pinion angle and gain a little more caster but have no idea how far.

First impression is it actually drive pretty decent. The steering wheel comes back to center, and on the short ride home and cruise over one of the worst roads in the county, no hint of death wobble. Now, with minimum toe and almost no caster, this is a drivers car at the moment. No looking at your phone at 75. Also be gentle on turning. It does grab and turn very quickly as expected with very little caster. No delay or mush of any kind. But not to the point of being twitchy, but very close to it.

Since I have 32s, 1.3 isn't as bad as the stock 29s would be at this caster. The bigger the radius is, the further off center you go from center. So maybe it is acting like a stock shoed WJ with 2.5 degrees caster?? I'm curious but not so much as to run the numbers on the weekend.

So will let it settle in and may fine tune it for a little less pinion angle and a little more caster, as well as slightly tweak the rear pinion angle. And top off the diff fluid in both and get the greasy gun out. And play with sway bar angles since i am higher than I planned to be, and get it out and check clearances. Tire clearances with the 32's may be another can of worms I'm stepping into. Tinker tinker tinker!

 

[MrWilsonWJ]

Are you running adjustable lowers in the front? Mine are adjustable upper and lower and I pushed the axle forward a bit and it gains you a tiny bit more to play with while setting angles ( driveline angle) and some clearance at the back for bigger tires. I think I started with +1" but that was too much and caused clearance issues with up travel, pretty sure I'm around 1/2"-3/4" now. I don't remember where I found the degree for stock sway bar angle but I think it's supposed to be about 30 degrees. One of my employees has a stock WJ, I can always measure it for you if you can't find the stock angle online. I know when I adjusted my Discos to get the sway bar closer to factory it helped with handling.

 

[JimBill]

Are you running adjustable lowers in the front? Mine are adjustable upper and lower and I pushed the axle forward a bit and it gains you a tiny bit more to play with while setting angles ( driveline angle) and some clearance at the back for bigger tires. I think I started with +1" but that was too much and caused clearance issues with up travel, pretty sure I'm around 1/2"-3/4" now. I don't remember where I found the degree for stock sway bar angle but I think it's supposed to be about 30 degrees. One of my employees has a stock WJ, I can always measure it for you if you can't find the stock angle online. I know when I adjusted my Discos to get the sway bar closer to factory it helped with handling.

Getting the bars reasonably close to stock does really help handling. I should be fine looking them up on-line. Yes, have all adjustable control arms. Good idea on stretching the front axle location, every little bit helps. Not sure I have much room to move but after testing this weekends work I should have an idea.

 

[JimBill]

More fine tuning. Was going to take the plastic out of the front fender wells, but ended up trimming the first known contact point on the bumper. Will flex it out and see where the witness marks are and go from there. Also to slightly help the caster issue, I took the spring spacers out of the rear. That took the back down 3/8 of an inch, thus rotating the front back ever so lightly. Insignificant, but what the heck. I like the look a little better.
Since the rear sway bar links were sized for a 3 inch lift, made and added 3/4 inch spacers for the mounting brackets to match actual lift. Between the bracket spacers and removing the spring spacers, rear sway bar angle looks pretty good now.

Lastly, I was having issues with my brake booster leaking down every time I shut off. And once on the trail did loose vacuum assist once on the brakes. Was looking at a PITA brake booster replacement I wasn't looking forward to. Luckily, snooped around and found the vacuum hose was a poor fit to the manifold port. Added a spring clip and now good to go. I'll take the simple fix any day.

 

[JimBill]

A quick test Sunday showed the disconnected front end was still hitting inside the wheel well, and a little on the passenger side bumper. Who knows int he rear, the heavy duty sway bar never met the bumpstops. Looks like I will have to load it up to see. Afte the flex test took it home and removed the first two pieces of sheet metal. Kept the plastic wheel well liners for now.
At the low caster number it actually feels more stable over roadway bumps, potholes, and chop. So far so good.

 

[MrWilsonWJ]

If you are running the Addco HD sway bar watch the mounts pretty close. It doesn't take much wheeling/flexing to have the mounts start to tare out. I didn't think I was wheeling mine hard enough to have that issue but after 1 season of off road and trails mine started to rip. It starts to flex the frame where the bolts go and will crack it, sounds like you are twisting a pop can back and forth. Just an FYI since it sounds like you plan to take it off road.

 

[JimBill]

If you are running the Addco HD sway bar watch the mounts pretty close. It doesn't take much wheeling/flexing to have the mounts start to tare out. I didn't think I was wheeling mine hard enough to have that issue but after 1 season of off road and trails mine started to rip. It starts to flex the frame where the bolts go and will crack it, sounds like you are twisting a pop can back and forth. Just an FYI since it sounds like you plan to take it off road.

Thanks for the heads up! When I bought the WJ it had the Addco, and I switched to a junkyard stock bar and ran it for years on and off road. I love the rear flex of the stock bar, but it shows how weak it is. The last 2000+ mile round trip to Washington convinced me to put the Addco back on, and figured I needed it with the soft IRO springs anyhow. Unfortunately the stocker went to the scrapyard last clean up, but it is on my mind to go to Pick-N-Pull and grab another.

A couple of years ago I determined I needed a 5/8 or 3/4 inch rear bar to be a near perfect compromise. Of course bolt in options do not exist for the WJ lol.

Again thank you for the heads up. Your experience tells me I need to run the stock bar when I plan to wheel, and the Addco when I daily drive it.

 

[JimBill]

Monitor Pass, weekend Aug 4-6 2023

A nice little trip with friends to explore somewhere we have not been. Monitor Pass BLM area in the Eastern Sierras. Met friends in Snelling, then drove Sanora Pass to Hwy 395, then up Hwy 89 to Monitor Pass. Nice little trip to see how all the WJ mods are working. Trails mostly a 2, with a few spots maybe a soft 3 here and there. My battery operated chainsaw was essential to get the 4 runner with rooftop tent through a number of spots. Great relaxing trip with new pinstripes to remember it by.

 

[JimBill]

Monitor Pass, WJ rundown after the mods- 3" IRO springs, 265/75-16 LTs (32" ish tires), bumpstop spacer length tweeks, front wheel well and bumper trimming, spare on roof, factory rear sway bar and factory front (disconnected on trail), with 3 day off grid load out:

Leaving home- (tires at 28 psi) Pacheco Pass was a fun introduction to sway and wandering. Not quite white knuckle but not comfortable. Was wishing I had the big rear sway bar on. Definitely drives like a lifted Jeep. At altitude could really feel the big tires and shift points. Had to wind the piss out of it to get over Sonora Pass. No issues but shift points definitely not optimal. Good news is wound in 1st gear climbing past 8900 ft temp gauge didn't move. Kinda wish for bigger brakes as well when heading down the 26 percent grade. Vibes feel like they are from tires, drive line u-joint angles are where I want them.

Trail- (tires at 16 psi, front disconnected) Lots of Sierra chop when not on dusty powdered dirt. I love the IRO springs compared to the blown out stockers and budget boost they replaced. Much less harsh, never bottomed out, and felt much more sure footed. Never once heard or felt any tire rubbing. (only rubbing is on the lower control arms in the front when turned near lock either direction). All good, and a definite improvement in feel, clearance, and tire grip. Aired down I could really feel the tire aggressive tread, almost lug by lug when creeping- new to me since I have only ran ATs prior to this. .

Heading home (tires at 30 PSI). A little more in the tires helped a bunch, but not enough. Did bottom out front suspension very hard on a culvert cut/repave on Hwy 88 at Capers lake. (watch out motorcyclists, they will throw you off your bike as we saw one down looking very bad). Took back roads through the central valley and the wind kept me totally focused on driving. Very much likes to wander due to not enough caster and the small sway bar in the rear. Inspection today showed no damage from hard bottom out, except one front bumpstop cup shows the foam collapsed completely and the metal cup was a little deformed from the front axle pad. Track bar stayed out of the oil pan so all is good, and tires never barked contact with fenders.

I do have a new steering box coming, lets see if that helps the wind wandering. At a headscratcher now on the rear sway bar. Big one is too much for off road flex and small one sucks on road. Wish someone made a 3/4 inch diameter bar. Also very curious how the same trip would be with the OME HD psrings in. Likely a heck of a lot better on pavement, but I wonder if they will ride and flex as nice on the trail.

Tire on roof sucks, despite the KOR tire rack working perfectly. Wonder if I can sledge hammer my spare tire well to fit it. Do not want to mount to rear hatch and loose rear visibility (HK solution). Once past the 30.5 tire size a rear swing arm is almost a must. So at 32's (267/75-16), clearance gets interesting if you want to disconnect, tire storage is an issue, shift points and braking become interesting, and Vari-Locks start to complain. On return rear vari lock very unhappy. I do not have the additive potion correct for it's personality. Will have to drain fluid and start over, this time with Mopar additive.

No cooling issues with AC on and pulling high RPM up Hwy 88, and tripple digit temps all the way home. At one point over Sonora pass my outside temp gauge red 109, but that was from the slow speed and heat pouring out of the engine compartment (it was 91 outside!!!!!). Point made for hood vents.

 

[Hernandez59]

Wow sounded like great adventure.

 

[JimBill]

Link to a great website of WJ information. Link will take you to the sway bar page but from there is a ton of WJ info documented.

Jeep Grand Cherokee WJ - Sway bars, factory (wjbible.com)

This tidbit was invaluable information for sorting out my options. The data given appears reasonable to expectations- so out of laziness I accept it as best known. (credit to wjbible.com):

 

[AggieOE]

Love the wheel choice and tire combo. Looks great! Adventures look fun too.