Need some serious help here please. I had my car aligned this past march after I changed over to Koni dampers. The car is lowered 1.5" with FRPP springs. My front tires are 275/35/19's. Because of their width and the car being lowered you cannot see the inner edge of the tires unless the wheels are cut to one side completely so I never really look at them. Well I parked the car yesterday to pickup my kid at daycare and had the wheels cut and when I came back to the car I see the inner edge of the drivers tire staring me in the face and its pretty ugly. nearly bald on the edge and instead of being rounded off like normal its kind of deformed looking. Passenger tire is better but still not good. Plenty of meat in the middle and outer edge of the tire, but the inner edges are jacked pretty good. So I head to the tire shop this morning and spoke with the manager about my $400 worth of tire being ruined in 6 months and he was pretty cool about it. They pulled the car in and checked the alignment. Results are below. He says that the results are within factory spec. I dont know enough to know if thats true or not. I do know that something somewhere is very wrong. What I need is someone with actual factual knowledge to tell me if the car should be aligned differently or if something else could possibly be causing this. I believe the shop is prepared to make this right, but I need hard evidence that the mistake is theirs before I can push in that direction.

 

It's true... sort of.

OE Spec is actually -.75, but then there is the +/- .75 degrees, meaning that anything from 0 to -1.5 is "in spec". -1.5 is way too much for a street car that sees no autox or track use. You need to get that number down, preferably with something good like Steeda HD mounts (camber plates), or camber bolts (much cheaper, but can be prone to slipping and don't fix the wear upper mount issue from Ford).

That's why your tires are worn out on the inside.

And before you ask... Why did Ford do that with the spec? My guess is it was the cheap way to have no issue with Shelby GT's which are lowered on FRPP springs and have no camber adjustment either. If they were -1.5 (which is common) then they can say it's in spec, and if it wears the tires out "it's a performance car". Plus they came with hard tires in the form of 400 treadwear BFG's. If you put something softer and stickier on you'll kill 'em faster.

 

So what your saying is I have no recourse with the shop. They did their job? But I should get a new alignment? What numbers should I be shooting for? The tire with the most negative camber is worn wore then the lesser side. Oh, and your right, this is a pure street car. Daily driver. Tires are Kumho Ecsta SPT. 320 Treadwear. I have camber bolts installed.

 

They did their job... not sure they did it right, or maybe they did but the camber bolts slipped (this can and does happen). Do you have your initial alignment sheet to see where it was when it left them the first time? If it's the same as now, then it didn't slip and they just didn't set it up as well as they could have. If it's different then they slipped and that's not their fault.

 

Sam,

Thank you for taking the time to give some great information here on the board as well as the phone. It will go a long way towards fixing my issue and avoiding it in the future, now that I have some understanding of alignment specs.

 

the camber bolts didnt slip, this would cause the toe to be out of spec as well. any change to caster or camber will effect toe. i agree with sam, get your camber down to .75- and you should be ok.

 

Funny you mention that jwog666, that's one of things I mentioned to Tim (sorry, pennywise) on the phone.

 

Quick update: Spoke with the manager this morning and they are going to realign for me this Friday. Again, thanks for the responses!

 

Hope things go better for you this time. Glad I could help.

 

Make sure they set the toe properly.

I'm running on my '07 Mustang -2.5 degrees camber all of the time, and I don't experience abnormal wear, except for once I set my toe out way too big, and THEN it started to eat my tires on the inside.

It's my experience that improper toe eats tires, not camber. That being said, there is no reason for huge negative camber on a street-driven car (as Sam shared) unless needed for competition, and I autocross a lot.