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schuvwj
10-05-2003, 11:26 AM
After painting my brake calipers yesterday I took my Machinist calipers and measured my tire tread wear with 17,000 mile on my MM.

1) 1st I measured my spare tire, 300A, to see how much rubber these tires had when new. I measured several areas to get an average and the spare had 0.225” of usable rubber when measuring from the wear bars.

2) Measured the front tires the same way, which have had 32 psi since day one and they had 0.150” of tread wear left. Wear measurement was even across both front tires.

3) Measured my rear tires and I found something very different. The outside and inside treat measurements were both 0.150” as the front but the center treat on both rear tires only had 0.075” of rubber left. This uneven wear on the rears was do to having 32 psi for about the first 10,000 miles. Now I am running 28 psi in the rears.

Summary:
Front tires – 30 psi to 32 psi have given me very good even wear.

Rear tires – 28 psi to 30 psi seemed best if you’re not hauling anything. (32 psi is too high and will cause center of tires to wear prematurely).

My 2 cents!

Glenn
10-05-2003, 11:40 AM
Would be interested in your comments on the 2004 MM tire pressure of 35 psi. Is it just CAFE. I removed my rear tires yesterday to install Ford "splash guards" and I noticed the centers were wearing more then the edges. The fronts look O.K. My MM has 9,000 miles.

schuvwj
10-05-2003, 12:42 PM
Originally posted by Glenn
Would be interested in your comments on the 2004 MM tire pressure of 35 psi. Is it just CAFE. I removed my rear tires yesterday to install Ford "splash guards" and I noticed the centers were wearing more then the edges. The fronts look O.K. My MM has 9,000 miles.

Glenn, everytime I go to my local F/M dealer where I bought my 03-MM and have the oil changed they always put 32-35 psi in all my tires, front and rear. The first thing I do when I get home is let the air out to 30psi front and 28 psi in rear. If I had the same BF Goodrich tires on my 04-MM I would not run over 30psi in the rear!

Have a Good One!

Marauderman
10-05-2003, 01:42 PM
Tires are strange--I run 35psi all around and all tires are wearing even ...go figure..........Tom

67435animal
10-05-2003, 02:42 PM
I had been running 35 PSI all around (10K miles currently) but based on the above post, I'll try 32 front and 30 rear and see how it goes.

Bob

uwsacf
10-05-2003, 03:17 PM
I'm running 40 all the way around and they are wearing just fine....

Most of my driving is highway though (134 miles daily)

looking97233
10-05-2003, 06:23 PM
What BFG has to say about it:

http://www.bfgoodrichtires.com/bfgapp/experts/index.jsp?style=2


Topic: Tire Performance
Issue: Even Tire Wear

To get even tire wear when using DOT-approved tires, you must be very careful not to use too low a tire pressure. Probably the biggest adjustment you can make to improve tire wear is in your driving. Avoid sliding the tires or locking up the wheels under braking, and drive as smoothly as possible.

I run 40 in front, 38 in back. Wearing evenly.
IMO: The sidewalls of our tires are quite stiff, so running less air in them has the reverse effect as with a tire with softer side walls. Just my .02.

03SILVERSTREAK
10-05-2003, 07:29 PM
Speaking of uneven wear I just visited the BF Goodrich Tires.com website and checked reccommend tire pressure . For both front and rear tires BF Goodrich reccommends 30 P.S.I. all around . the tag on my gas tank door says 32 P.S.I all around . what gives and who should we believe ? I'll stick to what BF Goodrich says after all it is their product...

schuvwj
10-05-2003, 07:59 PM
Originally posted by ADELG670
Speaking of uneven wear I just visited the BF Goodrich Tires.com website and checked reccommend tire pressure . For both front and rear tires BF Goodrich reccommends 30 P.S.I. all around . the tag on my gas tank door says 32 P.S.I all around . what gives and who should we believe ? I'll stick to what BF Goodrich says after all it is their product...

SILVERSTREAK I’m confused on how there can be so many different air pressures used on the same tires and cars with very different wear patterns? If one person can run 35 psi to 40 psi in the rear tires with even wear and another can not the only other thing I can think of is tire consistency!

Maybe I need to go to my F/M Dealer and voice my opinion!

Thanks!