Negative camber only in reverse?

[Colby_e32]

I just rebuilt my whole front end, using new moog upper control arms, with offset bushings with new balljoints, new lower balljoints, new GM pitman arm, idler arm, new inner and outer tie rods.

I switched from stock decranked keys, to belltech keys was the only “change”

truck is lowered 3.5” front, and 5” rear.


today I noticed when going in reverse the wheels camber in. Probably 3-4 degrees.

when I pull forward the wheels straighten up. It doesn’t seem like the toe changes much at all.

Any idea what could be wrong? I’ve read about this happening on Ford vehicles but never a Chevy.

it may have been doing it previously, but I never noticed it...

 

[exp500]

Sounds like your Alignment cams are loose.

 

[gooffeyguy]

Does it also do it when going forward and braking hard?

 

[Colby_e32]

Does it also do it when going forward and braking hard?

here’s the deal, I got finished installing the suspension Friday night, Saturday morning I was dialing in the ride height by adjusting the keys a few turns.
Every time I backed out of the shop to measure I had crazy camber.

I’d go drive it, pull back in, wheels straight as an arrow.

I have yet to notice if it does it during hard braking, but going forward the wheels are straight.

literally as soon as I put it in reverse and move back a foot, the wheels lean in. All parts are new. There’s no way a part is causing this.

 

[gooffeyguy]

Just trying to rule out if weight transfer was effecting it.

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[Colby_e32]

Just trying to rule out if weight transfer was effecting it.

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I can tell you for sure the cam bolts are tight.

What I’m thinking is the torsion keys are causing the issue, almost as if they aren’t supporting the weight of the truck as well as the stock decranked keys were. It’s sitting at the same height as before. 31 1/2” front ground to fender on a 285/50/20 tire.

 

[wjburken]

A couple questions.

1) Was your vehicle professionally aligned after you installed the new suspension components? Have you had it rechecked?

2) What is the condition of your jounce stops?

3) When you say the camber changes, what are you seeing/feeling that makes you say this? Are you able to measure it as being different or are you just feeling a difference in your steering that leads you to say it is changing?

 

[Colby_e32]

A couple questions.

1) Was your vehicle professionally aligned after you installed the new suspension components? Have you had it rechecked?

2) What is the condition of your jounce stops?

3) When you say the camber changes, what are you seeing/feeling that makes you say this? Are you able to measure it as being different or are you just feeling a difference in your steering that leads you to say it is changing?

Truck has not been aligned yet, it was aligned a week ago. I had 2 degrees of negative camber, caster was perfect, toe was perfect. I installed the moog problem solver upper arms which offer 2 degrees of positive camber. the wheel sits perfectly level now according to my camber gauge which mounts to the hub. That problem has been solved by swapping to the offset bushing upper arms.

jounce stops are like new, they are belltech jounce stops, and have been installed for several months.

when in reverse you can install the camber gauge onto the hub, and watch the wheel physically lean in 4 degrees. I have a video i can post a link to so you guys can watch this happen.

 

[Colby_e32]

I’ll upload a better video maybe with the camber gauge installed.

 

[wjburken]

You can see the wheel roll in and out, that is for sure. To get that much movement, there either has to be something that is not tight or something not seated properly. Have you checked your toe angles? If the front is toed in, it will want to pull the bottom of your wheels in going forward and pull the bottom of your wheels out going backward.

Personally, I'm not sure I would spend much more time trying to diagnose it as you should get it aligned again no matter what. I know you think that the only "change" is your keys, the fact is you replaced quite a few components up there and it needs to be re-aligned properly.

 

[Colby_e32]

You can see the wheel roll in and out, that is for sure. To get that much movement, there either has to be something that is not tight or something not seated properly. Have you checked your toe angles? If the front is toed in, it will want to pull the bottom of your wheels in going forward and pull the bottom of your wheels out going backward.

Personally, I'm not sure I would spend much more time trying to diagnose it as you should get it aligned again no matter what. I know you think that the only "change" is your keys, the fact is you replaced quite a few components up there and it needs to be re-aligned properly.

Absolutely. It’s going to the alignment shop this week. However I wanted to make sure there was no major problem before doing so. I do all my work myself other than alignments as I don’t have an alignment rack.

im certain the toe is off, but camber and caster are within specs according to my gauges. I guess we shall see.

I was mainly concerned and wondering if I have the torsion keys indexed wrong or something. I marked the torsion bar on the control arm before removing it, made sure it was back in the same position upon reinstallation,

but I was not able to Mark the key itself as there’s no room for a paint marker inside the crossmember.

 

[wjburken]

Absolutely. It’s going to the alignment shop this week. However I wanted to make sure there was no major problem before doing so. I do all my work myself other than alignments as I don’t have an alignment rack.

im certain the toe is off, but camber and caster are within specs according to my gauges. I guess we shall see.

I was mainly concerned and wondering if I have the torsion keys indexed wrong or something. I marked the torsion bar on the control arm before removing it, made sure it was back in the same position upon reinstallation,

but I was not able to Mark the key itself as there’s no room for a paint marker inside the crossmember.

I don't think changing your keys would cause what you are seeing assuming you were able to get reasonably close to where you have them cranked before. The toe angle being out would be my first suspicion.

Measuring caster and camber in a drive way or in a garage can be challenging unless you can zero out your gauges to accommodate any slope there may be in the concrete. It will allow you to get close, but as you said, without an alignment rack, that's all you can get.

 

[Colby_e32]

I don't think changing your keys would cause what you are seeing assuming you were able to get reasonably close to where you have them cranked before. The toe angle being out would be my first suspicion.

Measuring caster and camber in a drive way or in a garage can be challenging unless you can zero out your gauges to accommodate any slope there may be in the concrete. It will allow you to get close, but as you said, without an alignment rack, that's all you can get.

one big thing I forgot to mention, the front ride height decreases about 1” in reverse as well.
Maybe the toe is so far in, the wheels are being dragged while in reverse

 

[exp500]

Definately some severe movement! Don't drive it!
Put it where you can work, back up a foot till it moves. Inspect there. If it changes when you jack it, start over and crawl under with sharpie and put a reference mark on everything, Bushinggs, keys, Cams. Jack again and inspect. Its like you are missing control arm bushings.

 

[select127]

Both my lowered tahoe and yukon always did that, back up and you get neg camber. Pull forward and it straightens out. Left it alone and never had any issues.

 

[Colby_e32]

Both my lowered tahoe and yukon always did that, back up and you get neg camber. Pull forward and it straightens out. Left it alone and never had any issues.

weird as hell for sure.

I have quadruple checked everything, and can’t figure it out.

it’s at the alignment shop today. I’ll let them tell me if there’s anything crazy

 

[1992rs]

If everything checks out as tight, installed correctly AND you have not precisely adjusted your tie-rods since the refresh, id blame it on excessive toe. Happened to me before. An alignment fixed it.


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[Colby_e32]

Here is the alignment report guys.

Even after installing the moog control arms with offset bushings, camber couldn’t get into spec.

they recommended drop spindles which I already have. The truck isn’t even low (to me) and they can’t get it right.

I had less camber with stock keys, at the same ride height, makes no sense to me.

Any suggestions would be nice. The truck does drive fairly straight now that the toe is corrected.

 

[exp500]

Offset control arm bushings incorrectly installed.

 

[1992rs]

How much do you trust your alignment tech?

Looking at the sheet, it looks like they barely adjusted anything. They should be able to pull some caster out to gain some more positive camber. Aligning a wishbone like these trucks are kind of a push-pull situation, take caster, get camber and vice versa. Hence why you lost .3° caster and gained .3° positive camber on the Passenger side.

I started to think maybe the offset bushings were installed incorrectly, but if I’m reading it correctly, you purchased the moog UCA with the offset bushings already installed, correct? You should be able to get spec camber and still have good caster. But there’s been several horror stories over the years with these rigs not being able to get aligned after lowering.

Did the toe adjustment fix the camber change?

Can you also provide pictures of all 4 UCA brackets to see how it’s orientated?


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