4wd vs. 4wd z71

[ChevyGirl89]

What’s the difference in the suspension parts between a regular 4wd Tahoe vs a z71 4wd Tahoe? I know the rear springs are different lengths but what about the front suspension?

 

[wjburken]

What’s the difference in the suspension parts between a regular 4wd Tahoe vs a z71 4wd Tahoe? I know the rear springs are different lengths but what about the front suspension?

I’m pretty sure the Z71 came with different shocks. Rancho, I believe. At least that’s what I had on my 2004 & 2005 Z71 Silverados. If remember correctly, my trucks also came with a full skid plate package.

 

[ChevyGirl89]

My Tahoe had the rough country level lift with rear spring spacers and rough country shocks on it when I bought it. Since then I upgraded to the bilstein shocks. But we just drove to Tennessee yesterday and between everyone, luggage, hitch rack and cooler it’s squatting pretty good to where the right bump will have the tires scrub the fender liners. I have just seen the z71s sit higher and wanted to the what was different in suspension parts.

 

[MassHoe04]

I believe my 2004 Tahoe Z71 came with Bilstein shocks. Mine are a little crusty, but from the looks of it... I believe they are the originals that came with it. Still work fine. Coming up on 200k miles soon.

 

[Fless]

I'm not sure if there are OE suspensions other than the Z71 and the Premium Smooth Ride (maybe someone here knows) but the PSR rear springs are softer than the Z71's, and the PSR has Nivomat self-adjusting rear shocks that complement the softer springs.

I'm not aware of the front shock technical differences, but the aftermarket shocks are different part numbers for the different suspensions. I suspect that the PSR system has somewhat softer front shocks, but I have nothing to back that up.

EDIT: it looks like there is also a Z55 Autoride suspension available

 

[ChevyGirl89]

I put the bilstein shock on that are intended for a level lift. I just didn’t know if any other front suspension parts differ since the z71s look like they sit a little higher than a ls/lt

 

[wjburken]

I put the bilstein shock on that are intended for a level lift. I just didn’t know if any other front suspension parts differ since the z71s look like they sit a little higher than a ls/lt

If i recall correctly the only difference other than the shock might be the bump stop and how the torsion bars are set. I think the Z71 has different bump stops to work with torsion bars that are set for a higher ride height. That being said, it’s been a few years since I’ve owned or messed with that generation of truck.

 

[ChevyGirl89]

First pic is with just luggage, 2nd pic is was 2adults and baby on 2nd row and 1 third row seat with an adult. The luggage is in the other side of where the third row seat would be. It scrubs depending on how much lean there is while turning and depending on the bumps. We recently purchased a camper too so I figure the z71 spring would help out all around? Just not sure if I should ditch the rear spacer or keep it?

 

[Mudsport96]

Damn. Umm. Would maybe the Suburban rear springs have a higher weight capacity?

While it is not a Tahoe, my 95 f150 sagged bad with moderate weight. So i pulled out the factory spring spacer and put in a set of 2wd 8800 gvw f250 camper special springs. It gave me 1 inch of rake, but when loaded with my usual tools and equipment ( 500-600lbs) it sits dead level.
So maybe some 2500 burb springs would help if the drop in place of the stockers.

 

[Myfirstz71]

What’s the difference in the suspension parts between a regular 4wd Tahoe vs a z71 4wd Tahoe? I know the rear springs are different lengths but what about the front suspension?

If I remember correctly from reading on here, I believe that the z71 springs are 300 lbs heavier spring rate. Several discussion on here around the fact that replacing regular Tahoe springs with z71 springs would give about 1-1.5 inch rise in the rear due to the stiffer compression rate.

Not sure how this compares to a 2500 spring as mentioned.

 

[Fless]

What RPO codes do you have for suspension? If they are ZW7 with G65, that's the Premium Smooth Ride and that has softer rear springs to go with the Nivomat self-leveling rear shocks. If you have those codes, do you know if the rear springs were changed with the Rough Country lift?

 

[Doubeleive]

man my 00 yukon xl could be loaded to the gills with tons of people and luggage and it never sagged at all
that was with the nivomat's, somethings wrong there.

 

[ChevyGirl89]

I will have to look at the codes tomorrow, I dont know if the springs were ever changed. I just know the guy before me had the level lift put on and it has the spacers on top of the spring, they looked to be 1in. It does have almost 226k miles too.

 

[EddieC]

My '08 Z71 had different shocks. They were by no means harsh so I replaced them with the same when one failed after many years. Modern upgraded oem suspension is not rock hard like in the old days. I hesitated on our C5 vette but, again, the sporty suspension was very complacent.
I can't say what other suspension parts were different on the Z71 but I suspect the rear sway bar was an upgrade.
We also got 18" wheels in the package that look nice but a bit of an oddball tire size. They are not lacking in sidewall so the ride was not regrettable.

 

[ChevyGirl89]

So here are my codes, I did search the rough country level lift that’s on it and there are 3/4in spacers in the rear. Trying to decide if I should leave them when I upgrade to springs to the Moog HD ones.

 

[Fless]

I would venture a guess that it squats because the Nivomats were removed but the softer springs weren't. Perhaps the spacer was meant to compensate but that's not enough to overcome the soft springs. Bilstein indicates shock replacement for the rear shocks (from Nivomat to conventional) should include changing the springs. Is there a tag with a part number on your springs?

From RockAuto:

 

[ChevyGirl89]

Yeah when I got it, the man before had the rough country level kit with keys, spacers and shocks put on. The sway bar links were shot and the shocks weren’t the greatest so I bit the bullet and purchased these bilstein shocks. I have always had chevy trucks, this is my first Tahoe so I’m learning on the things that differ from the trucks. We just got back from vacation and done a roungh measurement and my front fenders are around 38 1/8 and the rear was about 36 7/8. But I haven’t had a chance to measure on flat concrete

 

[Myfirstz71]

The RPO code ZW7 refers to your suspension package. Z71 is obvious, Z55 is air ride. I would second @Fless’s assessment that the shocks were changed out from the nivomat to standard without taking into consideration the softer spring rate of the rear springs. If you change out the springs in the rear to Z71 OEM or the moog, this should resolve the sag.

You might even be able to ditch the spacer since the new spring will not sag nearly as much under the weight of the rear end. Try new springs with out spacer, take measurements, and if you don’t like it, easy enough to add the spacer back in.

 

[bobsburban]

The 5100 Bilsteins are good but aren't designed as springs (duh). I'd say call Moog and order their version of the Z71 coil springs, which should be what you have on a 1/2 ton SUV. I can confirm that when I did my Z55 delete on my 2011 Suburban, the springs I got from Moog were about 250 lbs stiffer than the Z55 springs, They were also about 2" longer. That should help. Given what was done to the front end to level the truck, it's little wonder the rear squats with that kind of rake. I fight the same issue on my Suburban when towing as I "leveled" my truck by setting the front springs on the first perch from bottom on my front 5100s. I'm still working with my wesight distribution hitch setup to get things as level as possible with 500-ish pounds of hitch weight and water and an ice chest full of drinks in the back of the Suburban.

Good luck.

Edit: pretty sure springs on 2500 trucks are all leaf springs, springs on 1/2 tons, except the really older ones, are coils. Not sure how that works into your year but if 2500 leaf springs are an option, that could be a good move if they fit. Otherwise, Moog is your friend; call them direct and verify the part number for their stiffest coils. I don't think GM makes/stocks these anymore. I had no luck when I was looking for them.

 

[OR VietVet]

The Moog spring number for Z71 is the 81069 springs. I did them on my Z71