Firestone Destination AT

[RedneckEnvoy]

Hi all,
We have a 2004 GMC Envoy XUV 5.3L SLT 4x4 running on 245 70 17 Firestone destination ATs on the stock wheels.

When turning you can feel the tires crunch in like and it feels like over 65mph you could roll it. I have driven tons of lifted SUVs and trucks and never really felt scared like that the vehicle is going to roll at high speeds even on hair pin turns.

I have the air pressure at what it says on the door and have tried different pressures to see if any helps but none.

I usually won't run Firestone tires but I heard such good reviews and the deal was to good to pass up on these ones on envoys and Trailblazers but I am begging to regret it.

My question is has anybody else experienced this?
Any way to fix it?

We do a lot of highway driving with twisty curvy roads and I would like to be able to take this car without being scared of it rolling.

When towing or on the backroads we travel it isn't that bad but unloaded with 4-5 people in it it is just plain scary.
Trav

 

[HARDTRAILZ]

Have you tried a chalk test to get proper inflation?

Are all the suspension components in good shape and swaybars and links solid?

 

[RedneckEnvoy]

Not sure what a chalk test is. I just put it at certain pressures changing from higher rear lower, rear higher front lower, both the same and all ranging at different pressures in 5psi intervals and then drove it on my roads.

Could it be the air suspension acting up? I can't tell if it is all the way down when I don't have a load off and everytime I put a load on it the truck automatically airs up but never hear it air down when I take the load off.
I have never had air suspension like this but have driven big dually 4x4 fords with air suspension like this.

Also I don't have TPMS (tire pressure monitoring system) not sure if that is usual on these cars I figured something this fancy would have it.

All the suspension parts are surprisingly in great shape (everything on the car seems to have quirks minus the drivetrain).
Trav

 

[HARDTRAILZ]

I personally hate TMPS and would remove, but it was not standard on the platform.

A chalk test is running a chalk line on the tire and seeing if it is a solid contact patch all the way across. Goggle for better info.

With 4x4 you want the same pressure front and rear.

Do you know the air susp is loading or is it just pumping? Does the suspension move? The airbags are known to develop leaks over time and many replace them with springs.

 

[RedneckEnvoy]

Wouldn't putting the tire pressure at different spots do effectively the same thing as the chalk test?

I have already looked to see if all the tread is touching the ground and such and it is and it seems solid so to speak (not sure how to explain it).

I don't like the TPMS either only vehicle I have that has it is my 10 F150 but I like it on that truck for different reasons.

right now I have it set back at the pressure on the door and it is the same front and rear I just did it for testing.

I don't know what you mean by loading or pumping? The truck does raise back up to where it was once I put the trailer on and seems like it lowers but it has a ton of rake (front end looks like it is slammed and rear looks like it is jacked up).
I would love to put springs in it but right now it isn't in the budget and if I did I would lift it to get more tire clearance if the stock chevy IFS could handle bigger tires (sorry but never been a fan of Chevy IFS and wish I could SAS the envoy but mom won't let me. LOL)
Trav

 

[HARDTRAILZ]

You won't see with the naked eye like you will with a chalk test. My tires look good from 28-45 psi, but about 35-36 is right.

Sounds like the air bags are working, but your front springs are sagging possibly. Do you know if the shocks and struts have been done? Bounce on either bumper and see how they react if you don't know. Certainly is one commonly overlooked wear item on most vehicles.

My relatively stock IFS has handled 35s and some pretty good wheeling and work for awhile now. I have considered SAS, but when the TB keeps up or passes lifted Jeeps and many other rigs on and off roads, I have some difficulty in justifying it.



I do hope you can figure it out, because I really have complete faith in my truck and even without a rear swaybar have no issues from 0-100 or feel like it will tip over unless it one of the hairier trails .

 

[RedneckEnvoy]

I will have to try the chalk test although I doubt anything will come from it.

Shocks and all are fine I think you may be right about sagging springs. The truck was heavily abused before so I don't put it past anything. It is sad though because my 94 Explorer is in better shape then this thing.

I don't really need 35s I really more of just need 33s or so so that gives me a little insurance.

I love the car especially the power (I have never seen a suv with this much power bone stock naturally aspirated.)

I hope I figure it out too and hopefully it is cheap as I personally would like to keep pouring money into my baby (88 F150 4x4). LOL
Trav

 

[Sparky]

I have Destination AT, had them at stock size for around 65k or so, then I put my 2.5" lift on and now have them at 265/75/16. They have been very stable for me and I probably take turns a bit faster than maybe I should. I run 35 PSI front and rear in them, both when I had stock size and also now on the larger size.

How many miles on the truck, and what shocks are on it? Sway bars/links/bushings all OK? Ball joints and tie rod ends? I know it may be hard to see but how does the rubber on the mounts look?

If there is that much rake to it then it makes me wonder about the front springs as well, and also wonder what would cause that. My 02 has 208k miles on it, has been lifted since 185k, and I've never changed the springs.

 

[RedneckEnvoy]

Here is a pic of the rake granted that was a pic when I first got it with stock tires (please ignore the tarp when I got it the sun roof was open and getting things wet) It is the only pic I have of Snow whites hearse (Yes I do call it a hearse as it looks like one to me and most of my buddys around town here. LOL

122K about to hit 123K if I keep driving it as much as I do (hard to resist driving it being it gets the same mileage as my 10 F150 5.4L and keeps the miles off of it with just about 50hp less then it for now).
All bushings look great although they are original along with links and sway bars. Shocks are AC Delco but I want to put blistiens or Rancho on it (do they have them for envoy xuvs?)
Ball joints are either moog or ACDELCO being I have 14 vehicles with ball joints and 2 with forks (Harleys) it is hard to remember the exact brand. Tie rod ends are stock however are in the same shape as the ones on my 94 Explorer with brand new ones.
Mounts are in great shape (one of the things I noticed while changing plugs) however I would like one day to go full polyurethane. However most money is going toward rebuilding the engine for my 88 F150.


I am not sure if the rake is suppose to be like that or not their is only 2 envoys around here and they both are beat up big time and the only trailblazer is and ss and has the huge 6.2L (that is the size for it right?)



Also I did the chalk test (very easy to do just a bit time consuming) and it seemed like it was best at like you guys are saying 35psi so I had mom take it with my brother (I had something else to do) and he said it is performing a little better but he said it is still a little spooky.
Thanks for the help so far,
Trav

I have Destination AT, had them at stock size for around 65k or so, then I put my 2.5" lift on and now have them at 265/75/16. They have been very stable for me and I probably take turns a bit faster than maybe I should. I run 35 PSI front and rear in them, both when I had stock size and also now on the larger size.

How many miles on the truck, and what shocks are on it? Sway bars/links/bushings all OK? Ball joints and tie rod ends? I know it may be hard to see but how does the rubber on the mounts look?

If there is that much rake to it then it makes me wonder about the front springs as well, and also wonder what would cause that. My 02 has 208k miles on it, has been lifted since 185k, and I've never changed the springs.

 

[Robbabob]

Stock size Destination AT's our our '03, always drive too fast through the curves and no issues feeling like we're tipping over.

Just my $.02

 

[Sparky]

Original shocks at 123k and 11 years are going to be pretty well shot. Go with the Bilsteins IMO. I would suspect the shocks before the bushings.

Can you get a direct side shot? Hard to tell really from a 2/3 angle pic.

 

[RedneckEnvoy]

They aren't originals they are newer AC Delco shocks.

I won't be able to get a side pic for a little while but if I remember I will get one up.

Also took it yesterday and noticed it was 121500 miles not what I had said. My bad on that part. I seem to always say the miles higher then what it really is on this car.
Trav