Rear wheel toe on 90 suburban RWD

[richardberg]

My 90 Suburban pulls to the right, I’ve had it to Firestone twice for alignment and every time it pulls just as much to the right. Those guys don’t bother to test drive the car apparently and didn’t notice that the left rear wheel has a 0.2 degree negative toe (pointing out). I am guessing that’s the cause of the heavy right pull. The rear wheels are not adjustable. The car has not been in any major accident. A rear fender bender with damage to the rear bumpe was all. I’ve replaced the shocks. I doubt that the frame is bent. The distance between front and rear wheels seem to be the same from my measurement with a tape measurer. Any ideas? I’ve swapped around the wheels with no change.

 

[RecklessWOT]

There is no way to align the wheels on a solid rear axle. Especially if it's only one wheel, something is bent. Are you sure the whole axle isn't shifted?

 

[DoubleDingo]

Yeah, sounds like something is bent.

 

[Bextreme04]

My 90 Suburban pulls to the right, I’ve had it to Firestone twice for alignment and every time it pulls just as much to the right. Those guys don’t bother to test drive the car apparently and didn’t notice that the left rear wheel has a 0.2 degree negative toe (pointing out). I am guessing that’s the cause of the heavy right pull. The rear wheels are not adjustable. The car has not been in any major accident. A rear fender bender with damage to the rear bumpe was all. I’ve replaced the shocks. I doubt that the frame is bent. The distance between front and rear wheels seem to be the same from my measurement with a tape measurer. Any ideas? I’ve swapped around the wheels with no change.

The only possible way to have a single wheel out of alignment on a solid axle is to have a bent axle tube. That also shouldn't cause a pull in the steering. When was the last time you had the right front hub/bearing serviced? Same for the brakes? Checked the tire pressure?

 

[richardberg]

I’m glad to hear that a rear toe shouldn’t affect the steering. I haven’t checked the front hub but the wheels spin freely and I can jerk them and they seem tight. Maybe the front hub starts the issue when it’s under pressure and that’s why it’s pulling?

 

[Bextreme04]

I’m glad to hear that a rear toe shouldn’t affect the steering. I haven’t checked the front hub but the wheels spin freely and I can jerk them and they seem tight. Maybe the front hub starts the issue when it’s under pressure and that’s why it’s pulling?

It's hard to say. They should be checked and repacked with grease fairly regularly. It doesn't take a whole lot of difference in friction to cause a pull. The direction it pulls in will be the problem side. The only other thing that you can check that could cause a hard pull is the steering box being out of alignment. The box itself has a self centering function, so if someone did some weird things in trying to adjust the steering box compared to the linkage, compared to the steering shaft, you can end up in a strange state. You can check this by disconnecting the linkage from the pitman arm attached to the steering box while the wheels are pointed straight ahead. Then turn the steering wheel all the way to the left until it stops. Then turn it all the way to the right until it stops again while counting the number of turns it takes. Now turn it half that many of times back to the left and you should be centered. Now go look at the pitman arm and the steering linkage. Do they line up and go together without needing to move the pitman arm? If you need to move something, then it was out of alignment. Adjust the steering linkage arm to the pitman arm until they go together and you should be centered now. You will likely need to adjust the steering shaft or the actual steering wheel now to have it sit straight when the wheels are straight also if you had to change anything.

 

[Bextreme04]

Also, you never said in your post, but is this 2wd or 4wd?

 

[Ricko1966]

Fwiw I worked at Firestone briefly. Went there after working g at a really good mom and pop shop for years.I was told to quit test driving alignments. And if all adjustable angles were in the green it's good. Next please.

 

[CalSgt]

They should be giving you a print out showing before and after when you get an alignment... Post it up

 

[RecklessWOT]

Also, you never said in your post, but is this 2wd or 4wd?

The thread title says "90 suburban rwd" so I took that as meaning it's 2wd, like rwd only.

 

[bucket]

I'm betting on a simple tire pull or the castor is out on one side. Swap the front tires around and see if it pulls the other direction.

 

[bucket]

Nevermind about swapping the front wheels, I just realized you did that already.

It also could be a dragging front brake, but I assume you would have noticed excessive brake dust and heat in that corner. If castor is fine and all else checks out, I've seen a bad steering box cause a pull a few times in the past. Pretty rare though.

 

[Radiohead]

Two tenths of a degree of toe out in any wheel position is not going to do this. Period. Full stop.

The biggest problem you have is taking your truck to alignment morons. Without seeing the print out I can't tell you where I suspect the problem could be, but from what I gather, you have a schitt tire causing the pull. Rotate, test, get back to us.

Another thing to consider, is there enough caster offset for road crown?

 

[Ricko1966]

My 90 Suburban pulls to the right, I’ve had it to Firestone twice for alignment and every time it pulls just as much to the right. Those guys don’t bother to test drive the car apparently and didn’t notice that the left rear wheel has a 0.2 degree negative toe (pointing out). I am guessing that’s the cause of the heavy right pull. The rear wheels are not adjustable. The car has not been in any major accident. A rear fender bender with damage to the rear bumpe was all. I’ve replaced the shocks. I doubt that the frame is bent. The distance between front and rear wheels seem to be the same from my measurement with a tape measurer. Any ideas? I’ve swapped around the wheels with no change.

Have you ever asked them to diagnose why your car pulls right? Or did this start with you asking for a front end alignment thinking that was the fix,and did you ask for a front end alignment or a 4 wheel alignment?

 

[SquareRoot]

How did the OP notice the left rear wheel has two tenths of one degree toe out? Pretty sure it's not noticable to the eye or a measuring tape. This whole thread is based on assumptions.