Alignment issues- looking for advice

[tHatOne guY]

So after getting an alignment done at Firestone today, looked at my alignment print out and noticed it looked a bit off to me. After reading many posts concerning alignments and shifting the sub-frame to equalize the cross camber on the B6 I decided I'd need phone a friend on this one.

Taking many posts into consideration I did the following in preparation for the alignment:

Car is an 04' 1.8T USP with OE sport spring/shocks

DIY toe constant adjustment- all the way down to the notch
FCP full front control arm kit with TRE and hardware- bushes were shot on the oe arms
P/S rack pre-load adjust- loosened until knock was heard then tightened just enough to eliminate knocking sound
Talked with Firestone tech to custom set toe in- see align sheet

After the alignment the car drove much better with less noise in the cabin, significantly much less wander and tram-lining and the steering wheel wants to self-center now on it's own after making a turn. Before I would have to recenter the wheel after most turns. I even did the rack pre-load adjustment prior.


So the remaining issues I need you guy's help with are this...

I cannot find a caster spec anywhere in the Bentley- is there one? I am aware the lower control arms set the caster and it is not an adjustable angle.

Next, the camber on the driver side is at the max negative end of the spec but the passenger side is already past the negative spec by .4 a degree so shifting the sub-frame wouldn't bring this into tolerance but only make the driver side more negative and out of tolerance, unless I'm missing something?

Lastly, the car still drifts left. Now this I suspect is due to the camber. My guess is that since the side with the most positive camber is the left side and the right side tire is leaning more toward the opposite side inducing the left side drift.

Let me know what you guys think, I really wanna keep this car and get it all sorted. Without this site I don't think I would have made it this far. Well looking forward to your advice and thanks in advance.


Stay

Alignment_2016.jpg

[Mr.Avant]

Rule of thumb, camber pulls to the most positive. Caster pulls to the most negative.

Your camber values should result in a "0.4 degree pull" to the left. Caster appears it will cancel this some, with caster resulting in a "0.2 degree" pull right. Your final difference results in 0.2 degree difference to the left. Should hardly be enough to notice.

Many manufacturers now use a camber difference to equalize the forces of road crown, meaning optimal spec is not always the same side to side.

What are your tires condition? I have done alignments, only to find on the test drive that the vehicle wants to "drift" to one side or the other. This can be caused by what we call "tire pull". Poor tire condition can result in a constant drift in one direction. Doing a proper rotation and test drive is a quick way to check if tire condition is affecting the steering performance.

In this case a subframe shift could only be used to equalize camber outside of spec. Although that small of a difference shouldn't create a constant pull/drift.

[Furly]

You cant adjust caster on an audi.

If your steering rack was that loose and knocked, you probably have a failing rack.

[LINDW4LL]

It's my understanding that your subframe isn't properly centered if your camber is not even side-to-side.

Not sure why it's out of spec, but a little camber does not hurt anything whatsoever.

[old guy]

Overall I think your alignment looks pretty good. Your previous front toe alignment was horrid. I imagine you were chewing up your front tires at a furious rate and wandering all over the place.

You could go through the exercise to shift your subframe and even out the front camber but i doubt it will really make any difference in how the car performs. Once you add additional weight on the drivers side (get in the car and drive) the front left camber will increase slightly.

I suspect the slight pull to the left is more tire related than alignment related. If you have directional tread tires rotate front to rear and see if it makes a difference. If you have inner/outer or universal tread tread tires swap the left side tires with the right side tires and see if it makes a difference.

[tHatOne guY]

Rule of thumb, camber pulls to the most positive. Caster pulls to the most negative.

Your camber values should result in a "0.4 degree pull" to the left. Caster appears it will cancel this some, with caster resulting in a "0.2 degree" pull right. Your final difference results in 0.2 degree difference to the left. Should hardly be enough to notice.

Many manufacturers now use a camber difference to equalize the forces of road crown, meaning optimal spec is not always the same side to side.

What are your tires condition? I have done alignments, only to find on the test drive that the vehicle wants to "drift" to one side or the other. This can be caused by what we call "tire pull". Poor tire condition can result in a constant drift in one direction. Doing a proper rotation and test drive is a quick way to check if tire condition is affecting the steering performance.

In this case a subframe shift could only be used to equalize camber outside of spec. Although that small of a difference shouldn't create a constant pull/drift.

The tire condition had a me a little concerned as they are worn past half way now at 4/32nds front and 6/32nds rear but no shifted belts or sidewall bulges, no plugs or otherwise. Tire pressure is at the specified pressure on the door jamb. I plan to go with a set of Michelin Pilot Sports here in the next week or so and go back to the Firestone for another alignment- since I paid for their lifetime alignment service. It's the out of spec part that's got me. The car was never in an accident, the LCAs are all about a year old and still in good shape so why would the angles be out of spec maybe if the sub frame was bent...?

I'll do a quick cross rotation on the front axle and report back.

You cant adjust caster on an audi.

If your steering rack was that loose and knocked, you probably have a failing rack.

Yep bud I'm aware, was only looking for a spec for comparison to my readings. No failing rack, just did the rack adjustment exactly as the Bentley said, no knock/rattle heard when I was done and steering self-centers now.

It's my understanding that your subframe isn't properly centered if your camber is not even side-to-side.

Not sure why it's out of spec, but a little camber does not hurt anything whatsoever.

Certainly agree. Just not sure why it's not in spec anymore. Has me thinking maybe the control arms are out of spec but how rare and crazy is that right? No accidents or damage to the sub frame or uni body structure. After looking at many of the other posts about sub frame shifts usually one side for example is at a -.4 and -1.2 the other side so after the shift you end up with -.8 camber for the left and right side.

[Charles.waite]

the only thing that is adjustable in the front is Toe, as I'm sure you know. Camber can be evened from side to side by adjusting the subframe and caster as well I believe (though I could be wrong about caster). In the rear, you can adjust camber and toe.

Not sure why the SAI is different side to side. Maybe thats normal?

In all not a terrible alignment at all.

[JayDog747]

If you haven't done anything to the rear suspension, you need to replace the rear upper control arm bushings and the hub bushing. That should help with the tram-lining/wandering.

[tHatOne guY]

Overall I think your alignment looks pretty good. Your previous front toe alignment was horrid. I imagine you were chewing up your front tires at a furious rate and wandering all over the place.

You could go through the exercise to shift your subframe and even out the front camber but i doubt it will really make any difference in how the car performs. Once you add additional weight on the drivers side (get in the car and drive) the front left camber will increase slightly.

I suspect the slight pull to the left is more tire related than alignment related. If you have directional tread tires rotate front to rear and see if it makes a difference. If you have inner/outer or universal tread tread tires swap the left side tires with the right side tires and see if it makes a difference.

You are right, the wander was unreal. The plan is to cross rotate and see how it goes afterward. These are asymmetrical Nittos. If the pull continues I'll keep looking for the issue and if sub frame shift is it then that's what will happen, if not then a new set of Michelins are already on the way. In the past I have experienced even a new set of tires causing a drift. Hope your suspicions are right and it's just in the tires though.

the only thing that is adjustable in the front is Toe, as I'm sure you know. Camber can be evened from side to side by adjusting the subframe and caster as well I believe (though I could be wrong about caster). In the rear, you can adjust camber and toe.

Not sure why the SAI is different side to side. Maybe thats normal?

In all not a terrible alignment at all.

Much more satisfied with the alignment now to the previous set up. I'll keep searching the forum for a few more alignment sheets to compare to and esp look for the SAI angles to compare.

If you haven't done anything to the rear suspension, you need to replace the rear upper control arm bushings and the hub bushing. That should help with the tram-lining/wandering.

No wander or tram-lining now after setting the front toe-in so low. Before the alignment it was all over the place. Glad you mentioned the rear, the thought of a bad rear control arm bushing(s) had crossed my mind a few times as I do know a bad bush can cause the rear axle to steer the car due to too much deflection affecting the rear toe i.e change of thrust angle in and out of throttle.

Can you elaborate on this hub bushing please? I'll admit the front has had most of my attention kinda neglected the rear.

[chad99]

I just had an alignment done today. I can never remember much anything about alignment besides camber and toe but my left SAI is 4.7 and right 4.5 with cross SAI at 0.2 deg

[JayDog747]

Alot of people ignore the rear suspension and don't realize that's the cause of their problem. The upper control arm and hub bushing take the brunt of the punishment. Here is a DIY on the upper control arm. As you page down to the end, there is a diagram of the rear suspension. It's number 13. You can even take it a step more and replace number 15, the tie rod.

http://www.audizine.com/forum/showth...l-arm-bushings

Glad to see you picked the PSS. You won't regret it. I run them and the Pilot Alpin in the winter. Be sure to rotate them every 5K and read the owners manual for the proper tire pressure front/rear. Don't go by the plate on the door jam.

Also, and this is totally up to you, but I highly recommend taking it to an Audi dealer for the alignment. There are several alignment threads scattered here about guys taking it to Firestone only to end up taking to the dealer and have it done correctly

[evo_ski]

Centering the subframe is extremely easy.

[tHatOne guY]

Centering the subframe is extremely easy.

I have read this thread so many times I have it memorized. A lot of good info. I even did the sub frame alignment when I did the LCAs but I had to pull the engine and trans a few months after to replace the clutch and other pieces. Needles to say I didn't mark where the sub frame was prior to removal. When I went back with the engine/trans I just lined up the alignment holes at the corner w/ the little Audi tool and rolled with that. Having the engine on the stand and taking up so much garage space had me a bit impatient.

Alot of people ignore the rear suspension and don't realize that's the cause of their problem. The upper control arm and hub bushing take the brunt of the punishment. Here is a DIY on the upper control arm. As you page down to the end, there is a diagram of the rear suspension. It's number 13. You can even take it a step more and replace number 15, the tie rod.

http://www.audizine.com/forum/showth...l-arm-bushings

Glad to see you picked the PSS. You won't regret it. I run them and the Pilot Alpin in the winter. Be sure to rotate them every 5K and read the owners manual for the proper tire pressure front/rear. Don't go by the plate on the door jam.

Also, and this is totally up to you, but I highly recommend taking it to an Audi dealer for the alignment. There are several alignment threads scattered here about guys taking it to Firestone only to end up taking to the dealer and have it done correctly

Glad to hear the PSS are a good choice. Ran Michelins on my bikes before for a decade or so and never looked back since. As far as the dealer alignment that may be what needs done. My local dealer charges 150$ plus tax for their alignment and at this point that amount is just a drop in the bucket. Before I give up an book that appointment I'm gonna try to eliminate everything else, within reason. Will be looking into the rears today. Thanks for the link.

[tHatOne guY]

Hey guys thanks for the advice!

It was the tires. Rotate and balance done at Discount and pull went to the opposite side of the car.

Appreciate the help fellas!

[old guy]

Thanks for the follow up on a resolution to the thread