Uneven rear tire wear

Topic: Uneven rear tire wear (Read 1435 times) previous topic - next topic

Uneven rear tire wear

April 24, 2008, 01:48:44 PM

Hello!
First of all sorry it's a little off topic as it's a Lincoln Town Car related question. But, it's still a Ford, huh? :D I think it's best place to ask questions like this.
I bought a 1985 Town Car strech limo lately. Replaced all the tires with brand new set of Coopers (about 100 miles on them). Today while looking at new exhaust system I noticed uneven rear right tire wear - about 1/4 or 1/5 of outer part of the thread shows some wear and little "toothing" (not sure if you have similar term as we use here). Do you have any ideas what it may be? I know strech limo is a little heavy and I was braking from over 70mph today, but I didn't hear any tire squeaking.
Is it possible that it's becouse of weak shocks? They have 90000 miles on them and they are still factory ones.
Thanks in advance for help!
Mariusz...

Uneven rear tire wear

Reply #1 – April 24, 2008, 02:18:11 PM

feathering? heck, the only thing i can thing of to check is if the rear axle is dogtracking and mebbe see if the rim is mounting without runout.

Uneven rear tire wear

Reply #2 – April 24, 2008, 03:23:47 PM

The limo goes straight all the way up to 80mph (haven't tried to drive it faster) and there's no vibration or suspicius sounds at higher speeds. Axles bearings have some play, but it's the same in my T-bird and rear tires are untouched.
Yup... I thought about feathering. I attached a pic of affected area of tire marked in red and feathering marked as red lines.

Uneven rear tire wear

Reply #3 – April 24, 2008, 10:37:29 PM

If that is the right rear, then what you are showing us is the front side of the tire. If it were possibly dogtracking, which is undetectable to the driver, then the inboard side of the left tire should have the same effect. If not, and that is only area of wear, then the right side of your axle may be tweaked forward a bit. Bad shocks would give bad wear across the whole surface of the tire.

Uneven rear tire wear

Reply #4 – April 25, 2008, 02:58:24 AM

Yup, that's front side of right tire. I'll take a look at the inner edge of left one soon. What are the possible causes of dogtracking? Is it possible that it was always this way after streching? Left rear spring is a little lower than the right, is it possible that it's somehow pulling axle toward one side?

Uneven rear tire wear

Reply #5 – April 25, 2008, 07:46:36 PM

This is just my two cents, but honestly, in ANY unexplicable tire wear I have expierienced... it's always been the rear shocks (and/or Axle dampers)

Uneven rear tire wear

Reply #6 – April 29, 2008, 01:26:46 PM

If it is a vehicle that has been converted to a limo, that may be the whole explanation for the dogtracking. Most rear drive vehicles have a very small allowance for thrust angle due to production variance, and they just align the front end to the thrust angle. If you are wearing the rear tires funny then you may have a different issue, causing the thrust angle to be way out of spec. It usually takes an alignment machine to find what is causeing it to be out of spec, unless something bent jumps right out at you.