My right front tire was wearing on the inside edge so I decided to take it to a Chevy dealer for an alignment check. As I suspected the Right camber was off. However, when I got it home and looked at the before and after numbers I noticed that the dealer adjusted the caster out of spec on the right front. So I took it back and had them re-adjust the right caster. When I reviewed the numbers I was surprised to see that the BEFORE numbers of the second dealer alignment did not = AFTER numbers of the first dealer alignmnet. The camber numbers were up to 60% different. The should have been close to equal - same machine only 1 day later!

After the second alignmnet I drove my vette for about 2 months and something just didn't feel right on the highway. It didn't seem as solid at 70 MPHas before the alignments. I also noted that the right front tire was still wearing. So I decided to take it to someone else to have it checked. I took it to Sears. After talking with the alignment tech I thought that he seemed competent. Again, the BEFORE numbers of the Sears alignment were way different than the AFTER numbers of the second dealer alignment. On top of that the Sears alignment tech told me that my right front alignment cams are maxed out so he couldn't dial in the right front caster to be in spec! Note that I have NOT hit any large potholes between alignments!

I can't believe this alignment mess! After THREE alignments I still don't have any confidence that my alignment is correct. On top of that I may have a problem with my right front adjusters! What do I do next? Are alignment machines that inaccurate??


Front

First Dealer
Before|After
Left Right | Left Right
Camber -.53 -.99 |-.36 -.30
Caster 7.75 6.83| 7.35 7.96
Total Toe .06 | .02

Second Dealer
Before | After
Left Right | Left Right
Camber -.59 -.36 |-.47 -.06
Caster 7.7 8.17 | 7.51 7.39
Total Toe .06 | .03

Sears
Before | After
Left Right | Left Right
Camber -.7 .2 | -.2 -.2
Caster 8.0 7.1 | 5.7 6.1
Total Toe -.02 | .06

 

I wouldn't have an alignment done at a dealship, I'd find a good old fashioned alignment shop!

 

Sears and/or the dealership do not equal an alignment shop. Go to somebody whose business survival depends on him doing good alignment work.

 

the machines need to be calibrated every so often and yes they do get out of spec. If you want to be 100% sure, the only way to do it is to get out a level, ruler and some string and be ready to spend an afternoon adjusting things.

 

I think you need MORE not less negative camber up front.


-0.5 to -1.0* camber
max but equal caster <--- VERY IMPORTANT TO BE EQUAL
1/16" toe out


I do my alignments by hand, string, meansureing tapes, camber plates, toe plates and smart caster triangle.

 

"I do my alignments by hand, string, meansureing tapes, camber plates, toe plates and smart caster triangle."

Where did you buy the alignment equipment? Do you have anything that shows the procedure?

 

http://www.metricchemical.com/align.PDF

 

David Farmers wed site has the info on DIY alignment.

http://www.pegasusautoracing.com

is where I got the Longacre Toe-In plates, and SmartCamber tool.

A.R.T. makes Laser Toe plates and toe gages.

 

Go to www.hunter.com. Find a shop near you that has Hunter's latest alignment system. Went to Pat Goss' (Motor Week) garage and he had the newest Hunter alignment system. Car acted like it was on square wheels before I took it to Pat. Had the alignment done and Road force balance of all four wheels. Never felt or rode better. That was 4 months ago and everything still feels right on. Good luck.

 

A while ago my alignment was way out of wack

I took it to a local shop with the latest Hunter and recent calibration.

They could not get my caster even side to side in the front and caused tire wear.

Finally took it to an alignment place where the guy sits in a pit with rulers and such....no technical/Hunter stuff. He was able to get the caster correct and car felt much better.

Then I had a steering problem which the dealer fixed necessitating another alignment. They found that the last guy had not set things to spec when they redid the alignment. They used a Hunter and gave me a printout which up me in the Z06 spec range. My car handles great and I get VERY even tire wear....all four corners.

My rack/steering is leaking again and I assume they will need to redo the alignment again after repairs........I will be requesting an exact redo of the last settings


DH

 

I have found that 99% of the time it's more of a operators error than a machine. If the guy doing the aligment doesn't know how to proper set up and use the alignemnt machine, then it's not going to be correct.
Another concern to check would be is something moving and not holding an alignment? OR is something premature worn out.

 

 

Thats been a big problem for me & my c5.I have had both my current fleet aligned 6 times & they screwed it all up.I dont know if its the machines or the operators.I have driven over 50 years legally & finally I had a beserk person come across to lanes of traffic,after hidding behind a big van & hit my s10.This little deal bent the side sway on my frame.I guess thats not too bad a rec. & I never caused any accidents. Anyway,afer it was fixed at,the front had to be aligned & aligned & aligned & aligned some more.They finally got it where it didnt wear the tires,but the steering whl was never straight,but that didnt matter,so I was finally done,until I bought the vette.It all started again,Keep in mind these are the only two vehicles that I have paid to align in 40 years,go figure....I took the guy to small claims on the vette as he had the toe set at about 1/2 inch toed out.This will cut the inside of the tires real quick.I whud say:dont go the stealership,tire store,Or regular garage.Also better get a referral too...That car is a piece of cake to do,I dont know whats going on....

 

While it's true some Sears do not specialize in alignments, but most do. I'm an ASE tech at one To me it sounds like a height problem with your readings. Either your tires were not equal or one was very low causing the car to be unlevel, or the technician did not align the vehicle at a perfect level height that is calibrated to the aligmnent machine. An unlevel height creates a different "frame angle" which will change the Caster readings. BTW, we use the new Hunter machines with wireless heads, they're great and ACCURATE machines(down to a reading the size of a human hair, something a string can never match in accuracy). In any case, your caster reading is not causing your inner tread wear(camber / toe....have the tech keep both settings near 0 degrees or slightly positive). However, an unstable feeling at high speed is a caster problem. Generally, the higher the caster, the more stable it should be, so I'd have my caster as high as specs allow, and keep the right side higher than the left side to offset for road crowns! good luck!

 

I'm going to be getting an alignment soon as my leaking rack is fixed.

Question: does it matter if the tire treads are really worn ??


DH

 

01vetter, you said your right front tire was wearing on the inside, look at your first specs for the "before" setting and you will find the right front camber at -.99 degree. That will wear the inside of the front tire.
I adjusted my car with my specs and have no wear problem. There definately wasn't any string used and you have to be very careful using a garage floor for the basis of making adjustments. If you think your floor is level, throw a bucket of water down and watch it puddle up in the low spots, and see where the cement stick up in the high spots. That's why alignment racks are steel platforms that are up off the floor where they can be leveled.
Of your specs, the last ones from Sears are the best to prevent the problems you describe. And if I was going to go to anyone above, The Nuts would be the guy I would want adjusting on my car, with my help of course. And I would make one bet that would be easy to win, get your alignment perfectly adjusted, take it out and drive it a mile, then put it back on the alignment rack and set back up for an alignment, you'll be amazed how much a mile changes the alignment, or (most likely) it just gets set up differently the second time than it was the first time, which accounts for the different readings.
The most important part of a good alignment is the tech doing the job, not where he works. The second part is the equipment, and there is a lot of good equipment out there, the newer stuff is just easier to set up and use.

 

no, it doesnt matter with the new machines, they will compensate for any small tire subtlities, just make sure the technician has all tires at 30 psi!

 

Ok....all tires the same pressure


DH