2018 Chevy Colorado Z71

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Two good Colorado suppliers are Midwest Overland Ind and 589FAB. More are coming onboard everyday. I just ordered a full set of supermod skids for my ZR2, steel drive shaft is next.
 
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great08

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Btw, don’t tell anyone about that GM comment. A lot of my family has worked for GM.
No worries. It does seem that GM puts it's A-Team engineers and Money on some vehicles and not others. Then it shows in the end product. I know the Blaser has some followers but have heard many bad things about it. GM is about to start making it again. I was hoping it would be a SUV variant of the Colorado... but turns out it is going to be a front wheel drive crossover(another one! lol)... which will end/ruin that name brand.

Your Tundra should be a tough/reliable beast. If I were on the market for a Full size it would be either that or the Silverado. Carcomplaints.com says that the Tundra has way less issues than the Silverado. Which makes sense since it has not been remodeled in so long. All of the bugs are worked out.

For midsize trucks however; The Colorado is showing to be a lot more reliable than the Tacoma.

Here is a link to the 2017 Colorado (the year they put in the new engine, transmission, and x-fer case) 3 complaints If you click on the engine complaint... you can see that it is for squeaky belts. lol
https://www.carcomplaints.com/Chevrolet/Colorado/2017/

Here is the link for the 2017 Tacoma with 44 complaints...
https://www.carcomplaints.com/Toyota/Tacoma/2017/

The 2016 Tacoma was WAAAY worse with 147 complaints. So Toyota may be already making progress to square away the issues. I have faith in them. Toyota is a good company.

I am betting that is why Chevy replaced the entire drive train out in 2017. The 2016s had 68 complaints. Mostly transmission and engine related. So GM is squaring that away as well.
 

great08

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Two good Colorado suppliers are Midwest Overland Ind and 589FAB. More are coming onboard everyday. I just ordered a full set of supermod skids for my ZR2, steel drive shaft is next.
I will check them out. Thanks!

A steel drive shaft would be a must for anyone wanting to make their vehicle as tough as possible for those super tough trails. I think I may leave mine aluminum since I like the fuel economy and power to the ground. Everything has it's pros/cons. I also live in a salty area. lol
 

great08

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I got a new air compressor today while waiting at Pep Boys getting new tires for the wife.

$60
Says it can inflate a car tire in about 1 minute and a truck tire in about 2 minutes.
Rebuildable
Can run for 40min@40psi@70degF outside
1/3HP motor
Uses (max)30A... as in it cannot hook into the cig lighter port(20A fused). So it has to be either hooked directly to the battery... or wired in directly to the battery later on. I am thinking in the bed.
There are better ones out there... but this is a massive upgrade to the pump I have had going on a few decades now. The old one is on it's last leg though. Partially melted and coming apart at the plug. It had to run a long time on each tire. lol
Now I can possibly inflate all my tires in less than 10min! I used to spend that long on each tire going from 30 to 35 psi. lol

IMG_0536.JPG
 

great08

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Fuel Economy:

Ever wonder what a modern truck with a 308HP engine, 8spd Automatic, and Four wheel drive (with mild all terrains) gets for fuel economy? Wonder how those stricter EPA fuel economy ratings worked out over the years? Well wonder no more.

I just did a 313 mile fuel economy test during real world use over the course of 3 days of mixed driving for my daily commute. This is about 1/4 to 1/3 City driving and the rest being hwy. The highways around here are flat with the speed limits set mostly to 60mph but one 55mph stretch and one 70mph stretch. I did the speed limit for 3 days everywhere I went. Using the 8spd automatic I managed to Never go above 2k rpm on the speedo... except when pulling onto the 70mph hwy section and blending into traffic. Started on a cold drive train every 50mi or so. (which kills fuel economy... but it's Summer right now so it's not as bad as it will be)

Rated:
18 City and 24 Hwy
Computer Calculated 26.0 exactly during test.
Fuel pump (used same one) hand calculations worked out to just over 25.45mpg! Not bad sir. Not bad at all....

If I had driven this far in this environment non-stop... my fuel economy would have been higher. If it was only hwy driving... I could have gotten 30MPG!!! Not bad to be able to do that with a focused/trained foot.

That all being said I could have just as easily gotten much worse. It is almost always more about the driver than the vehicle. Flat ground at low speeds helped a lot as well.

I found out that if I set the cruise @ 45mph my fuel economy would shoot up to 35-38mpg!

When I set the cruise to 25mph... my truck will shift into 4cyl mode and get around 30mpg. I tried that in 4HI and 4Auto and it worked as well.

Tire pressures set to recommended 35psi during hwy test portion.

Photographic evidence below. I now have a baseline to guesstimate how much my mods effect fuel economy. Soon I shall remove the front air dam and do another test.

IMG_0520.JPG


Preparing for a hurricane so I may possibly disappear for a while if the power goes off. It seems to go off during every normal thunder storm around here.
 

great08

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Here is a link to a ton of offroad bumpers that cost upwards of $2000 for some of them. Not for me but neat to look at.

https://www.carid.com/2018-chevy-colorado-off-road-bumpers/

I have been putting forth a lot of thought towards what path to take with my truck bed. Getting ready to brace for impact with a hurricane for a while. I will check back soon. Hopefully everything ends up well.

 

great08

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great08

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I performed and ops check of the Master Flow Tsunami MF-1050 air pump.

Observation... it is super quiet compared to my other much weaker air pump that is ~15yrs old.

It inflated my daughter's bike tires from flat/sand pressure to 40psi in around 5secs. Super fast!

There are several little attachments for the tip. When I put the fine tip on it... it felt like the air gun we use at work and should be good enough to knock most of the loose dust out of an air filter after a long dirt track. We set the air at work to blow around 30psi on our aircraft. This felt weaker @ around what 20psi would feel like at work. Should be good. Just remember to blow the dust back out of the filter and not deeper into it.

There is a nice carrying case that would be good for something like under-seat storage. The mount feet are metal and have large rubber inserts/feet that can be removed to mount the air pump onto something. More on that to come later.

It seems well made. I like it!



IMG_0536.JPG
 

great08

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Air Dam Removal:


I just used my spare time sitting around waiting on the hurricane to make landfall making the 1st mod to the truck! Well... ok... maybe the second. The first one was adding/riveting a front license plate holder to the front of my truck when I moved to Virginia a few months ago.

This mod took around an hour to do with a mini ratchet that will hold both 1/4" sockets and flush hold (T10) torxs bits. No the bumper did not have to come off. Yes the hands of a 6ft tall 200lb guy fit in there to get it done. The fuel economy test done in post #46 was with this mod in mind. I now can get a guess as to how much this will effect my fuel economy. I know it will be none around town... maybe 1 mpg on the hwy? who knows.

Either way.... if it is .5mpg or more I will be putting the air dam back on. I will be modifying it to where I can take it off in 2min with power tools in the future. How? By flipping the anchor nuts over and mounting all of the T10 screws upside down. A super simple and easy mod.

Pics of the new bumper ground clearance. It is like giving the truck a 4" suspension lift up front! Not bad. Look how much room is above the basketball I used for reference. There are only a few things under the truck that would snag on a basketball now. Should be great for what I need once I get some skids under there.

IMG_0545.JPG IMG_0541.JPG IMG_0542.JPG


And one last pic of the little anchor nuts(upside down). They just pop off and can be slipped onto the other half of the bolt on surface facing the opposite direction. Already did this for two of the bolts so they are not hanging below the bumper. I think the truck looks better! On that thought I may leave the air dam off!
IMG_0546.JPG
 

great08

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Differentials and Transfer Case Info:

The rear axle for the 3.6 engine is the Dana M220 with a 8.6" ring set. It appears that Range Rover and Jeep Wrangler Sahara use a variant of the same rear axle. Unless... the Colorado has the Wide version of the M220. In which case the Jeep Wrangler Rubicon uses that one. I will read into this more when time permitting.

The front axle is a Dana M200 IFS

Also, since I have the Z71 I got the rear auto locker(non-electric). Which is made by Eaton. Though... any Colorado with a tow package option will also have this. They are super simple and have been around for a long time. My last several trucks(Silverado and 1st gen Colorado) had the same thing and they were maintenance free for the over 200,000 miles I put on each of those trucks. No wires/Just gears and such. If you are wondering if you have that feature in your truck... look at the sticker in the glove box. If you have the G80 code then you have it.

If you are wondering what the importance of a locking rear diff is off-road... here is a slightly cheesy video describing how the Eaton G80 auto locker works and what the benefits are of having one that auto locks versus Electronic locking. The one thing they failed to mention in the vid is that the G80 will engage at speeds up to 20mph. In either forward or reverse. Pretend all of the 4WD vehicles are GMs and just focus on the fact that they had open diffs. It wont be so cheesy then. lol

On a side note... having a locking rear diff makes donuts on dry pavement possible as well.

The Transfer Case is made by Magna. The model is the MP3025G Auto-trac. I am having a hard time finding info on this. They make Xfer cases for many auto manufacturers as well... so it is their specialty and they should be pretty good.

4 Auto and 4HI can be engaged at speeds up to 75mph. With the truck in 4 Auto mode you can drive around on dry pavement without binding up the drive train. So if foul weather is headed your way you can just put it into 4 Auto a leave it there for months and not worry. 4WD does actually engage in 4 Auto... it just varies the amount of power getting diverted to the front wheels. AKA the center diff. is engaged... but unlocked. A very useful real-world feature. If in rough stuff I would use 4HI or 4Low though. They will be stronger and provide 100% power instantly to the wheel with traction (if you get a front locking diff as well). If say all 4 wheels are spinning and one suddenly grabs... then it has 100% of the power output. So don't let them spin too fast or things will snap possibly!

4 LOW can be engaged at speeds up to 3-4 mph.

Neutral mode is obviously for towing behind an RV and such... as in I will likely never use it.

Here is the only link I have found with info. on gear ratios and such for the Xfer case. I want to find out what the inner workings are.
https://www.gmfleetorderguide.com/NASApp/domestic/graytabcontroller.jsp?graytabtype=5&rpoid=58427&vehicleid=21147&regionID=1&section=oi_def

Magna Powertrain makes transfer cases and such for a great deal of different manufacturers. It appears that 60% of 4WD vehicles on the road use their transfer cases. That is 6 out of 10.
 
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great08

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Just did some price searching to get an idea of what it would cost to replace parts that get ripped off by rocks and such while out on the trail.

In the following link you can see that...
The air dam I just removed would be about $71 to replace.
The center plastic piece on the front bumper would be around $210 w/tow hook holes

https://www.genuinegmpartsdirect.com/v-2018-chevrolet-colorado--z71--3-6l-v6-gas/body--bumper-and-components-front

For the back steps...
To replace the steps, their brackets, etc... would be around $150 to $180 if I were to totally destroy all components on a whole corner. I would likely just bend the brackets back and replace the plastic cover for the step. Which would cost around $38 for the left Or $47 for the right side. I am betting they jacked the price up for the right side since that is the side most likely to get damage when off-road (furthest from driver). Man are they good. lol

https://www.genuinegmpartsdirect.com/v-2018-chevrolet-colorado--z71--3-6l-v6-gas/body--bumper-and-components-rear

The rear drive shaft would cost just $311 to replace! Nice....
Either left or right rear axle shafts would be $126. Not bad...

https://www.genuinegmpartsdirect.com/v-2018-chevrolet-colorado--z71--3-6l-v6-gas/rear-suspension--axle-housing

Both the left and right front shafts are priced @ $158
The important bit is that it IS the same part# for both. As in I would only need 1 spare if going somewhere crazy!
https://www.genuinegmpartsdirect.com/v-2018-chevrolet-colorado--z71--3-6l-v6-gas/front-suspension--axle-and-differential

The knuckle/spindles for the front are $80... upper control arm = $101... Lower control arm = $126
https://www.genuinegmpartsdirect.com/v-2018-chevrolet-colorado--z71--3-6l-v6-gas/front-suspension--suspension-components



If you can do the work yourself you can keep these trucks (all trucks) running like new forever. You just need to keep the rust/damage off of the frame.
 
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great08

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Z71 vs ZR2 drive train, steering, and suspension parts... which ones are the same? Lets see...

The following items have the Same Part Number on the gasser V6 Z71 and ZR2 trucks(auto transmission)... I am only checking the parts listed above.

The rear axle assembly on the Z71 and ZR2 both have the same part #s allegedly. The only part number I see different (only looked a few seconds) are the Left and Right Rear axle shafts.

The rear leaf springs and shocks are different. Just one DSSV shock is $604 my Z71 is $64

The rear drive shaft/prop shafts are identical.

Steering Gear assy... Identicle

Tie rod ends... different. For some reason the ZR2 is cheaper

Electric motor for steering gear assy... identical except one of the options



More to come... To be continued....
 
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great08

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Z71/ZR2 parts comparison continued....

Front Diff. Assy = Identical (ZR2 has an e-locker though front and rear... so I assume that does not come with the assy... or the #book is not accurate)
Front Half Shafts = Different (ZR2 are around $186 which is $30 more)
Front Stabilizer Bar and bar end links = Different (not surprised since mine is gargantuan... IE a hinderance off road. My bar is probably 1.5" thick!)
Front Shock Dust Boot = (2WD does not have this item) Both have the same one.
Front Coil Spring = Some match up but most don't Probably depends on engine and package.
Knuckle/Hub Assy, Upper and Lower A-Arms = All different (knew the A-arms were different)
Inner Tie Rod for steering = Different - The left/right sides are interchangeable and cheap(Same for the Outer Tie Rods!). As in $25 for the Z71 and $49 for the ZR2.
I could not find the front drive shaft. :(

EDIT: I have now finished updating the above info...

It looks like there is a lot shared and also a lot not shared between the two. What I have will work great for overlanding... but not as well for things like the Rubicon trail. I like how GM parts are priced well. I will be able to afford buying spares and bringing them with me.

Even those parts like the vapor canister are only $115 on this truck(or ABS module for $276). Some vehicles cost a lot for that kind of thing. I think that is why there are so many GM trucks still on the road with over 300k miles on them.
 
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Z71/ZR2 parts comparison continued....

Front Diff. Assy = Identical (ZR2 has an e-locker though front and rear... so I assume that does not come with the assy... or the #book is not accurate)
Front Half Shafts = Different (ZR2 are around $186 which is $30 more)
Front Stabilizer Bar and bar end links = Different (not surprised since mine is gargantuan... IE a hinderance off road. My bar is probably 1.5" thick!)


I have to go put a school back together after the hurricane... be back in a few hours most likely. I will update/edit this section when I get back...
The DSSV shocks also don’t require as big of a sway bar. Big benefit there.
 
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The DSSV shocks also don’t require as big of a sway bar. Big benefit there.
That is what went through my mind when I saw it. I remember popping some aftermarket inertial adaptive valving into the front forks on my old dual sport and a rear shock. The bike rode stiffer during acceleration, stopping, cornering, and coming off of jumps. However, when hitting bumps or driving over deep holes and such... the valving would open up and allow the tire to move faster up and down. So the ride was smoother on rough terrain with better traction. Doing the front and rear took the whole bike to a new level.

Here is a link to the front valves and rear shock replacement for my old bike.
store.ricorshocks.com/klr650_s/42.htm


Now back to updating my prior post with more info...
 

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Front & Rear Differentials....

This is what I have learned about the Diffs so far...
Made by Dana...
Front diff is M200 IFS.
Rear diff for 2.5 LCV(4cyl) is M210, seems to be the 8" ring gear one.
Rear diff for 3.6 LFX(2015-2016 V6)/LGZ(2017-Present V6) and 2.8 LWN(Diesel with monster tq) is M220, thus 8.6" ring geared.

Nickname for my rear is "Dana 46" allegedly

The new 2018 Jeep Wrangler JL diffs are...

JL Sport (standard)
M186 Front Axle / M200 Rear Axle (Possibly Solid axle variant of the front IFS we have)

JL Sahara (standard)
M186 Front Axle / M200 Rear Axle (See Above)

JL Rubicon (standard)
Dana M210 Wide Front Axle (possibly what the 4cyl colordo has in the rear)/ Dana M220 Wide Rear Axle (Possibly what we have in the rear)

JL Sahara (optional package)
M186 Front Axle / Dana Wide M220 Rear Axle (Possibly what we have in the rear)
 
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