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View Full Version : Rear Tire Wear...Again!!!



Marauderjack
04-08-2005, 04:15 AM
I spoke with Miles at the Tire Rack yesterday to get a price on a set of front tires for my car and explained the problems we all seem to have with the rears!! :(

He said that ALL CARS with "staggered" tire sizes wear the rears much faster than the fronts!! Typically Porches with larger rears "burn" two sets of rears for every set of fronts....I told him that I was on the third set of rears (2 weeks ago) and if I wasn't worried about the fronts they would probably outlast the third set of rears!! :confused:

My fronts were wearing on the inside until I took the pressure up to 40+ and now they are very even....BTW, running 42-44 in the rears and got 33K miles out of the last set!! :bows: They would have gone 35K+ but why chance it?? :confused:

My $.02 FWIW..... :coolman:

Marauderjack :bandit:

Krytin
04-08-2005, 04:11 PM
Yep - 38K miles and the second set is going bald down the middle. Ran this set @ 38 psi & the fist set @ 32 psi w/the same results - less than 20K miles to replacement. I have been driving a little harder lately....

DEFYANT
04-08-2005, 04:36 PM
hehe, I've been workin on mine too!!!

Bradley G
04-08-2005, 05:02 PM
I got new rears ready to go on.I got 18 K on the orig. set,I hope these new ones don't last that long!:D

MENINBLK
04-08-2005, 05:17 PM
There is a post at the BFGoodrich Forum.
BF Goodrich - KDWS Center Wear ??? (http://www.bfgoodrichtires.com/bfgapp/servlet/Controller/site.forums.LoadMessages?discu ssion_id=.1dcec03a&topic_id=.1dce8370)

The simple explanation is that we need an extra 5 - 7 lbs of pressure
on the DRIVE AXLE because the KDWS we use are WIDER,
and because our cars are considered high horsepowered....

The Pontiac GTO also suffers from this problem.
They run a very wide 17" KDWS and have accelerated center wear.

Marauderjack
04-09-2005, 03:14 AM
Softer compound on the center rib only?? How'd they do that?? :confused: :confused:

Marauderjack :cool:

dflynn5
04-09-2005, 09:46 AM
I always believed center wear == overinflation. Too late for the current set of tires.



However, take it from me as a Tire Designer (6 years) and Ex-Test Driver for BFG (6 years), rear wheel drive, high horsepower, and high torque applications that exhibit accelerated center rib wear usually benefit from INCREASING cold inflation pressures. Now I know absolutely everyone in the public domain will tell you accelerated center rib wear is caused by over inflation, but believe me it's also caused by under inflation on the 'driven axle'.

Sully008
04-09-2005, 10:35 AM
This is some good info! I'll have to check the pressure in my tires since I got the car on Monday. It probably only has the Ford recommended inflation.

RF Overlord
04-09-2005, 11:54 AM
Until now, I was saying: "NO WAY will INCREASING the tire pressure reduce center wear...that's bass-ackwards"...

But enough members here have said it, and now an honest-to-goodness tire design engineer has explained it, so I guess it's time for me to try it. I just went out and aired-up the Blackbird to 35F/38R. I hope y'all are right...

TechHeavy
04-09-2005, 01:14 PM
hehe, I've been workin on mine too!!!
LOL! Mine will be gone by the end of the month at this rate.... Man, it was a loooong winter! :D

jaywish
04-10-2005, 06:47 AM
Hi,

I intend to increase the pressure in the rears from the recommended specs but Ford installed the wrong sticker (from a Marquis, different vin & all) on my fuel door.

What is the ford spec front & rear?

Thanks
jay

RF Overlord
04-10-2005, 07:25 AM
What is the ford spec front & rear?

32F/32R for '03s...I think they raised it to 35F/35R for the '04s...

jaywish
04-10-2005, 07:38 AM
Thanks,

I,ve been running 34's

I will go to 35/38.

Jay



32F/32R for '03s...I think they raised it to 35F/35R for the '04s...

dflynn5
04-10-2005, 11:54 AM
The sticker has 35F/35R

I'm going with 35F/38R.

Rat
04-10-2005, 02:28 PM
Tell him (Miles) he is full of S--- I put the same size on all Four (As Rear) corners and started running 38 all the way around. Same thing as with the original set got 10K on this set and have rotated every 3K and they are going to hell in hurry(Center Wear on all now). I don't have a clue as what to do but just drive and pay. I talked to someone at tire Rack when I bought the last set and he recommended 28 front 32 rear.

Thanks:
Bob



I spoke with Miles at the Tire Rack yesterday to get a price on a set of front tires for my car and explained the problems we all seem to have with the rears!! :(

He said that ALL CARS with "staggered" tire sizes wear the rears much faster than the fronts!! Typically Porches with larger rears "burn" two sets of rears for every set of fronts....I told him that I was on the third set of rears (2 weeks ago) and if I wasn't worried about the fronts they would probably outlast the third set of rears!! :confused:

My fronts were wearing on the inside until I took the pressure up to 40+ and now they are very even....BTW, running 42-44 in the rears and got 33K miles out of the last set!! :bows: They would have gone 35K+ but why chance it?? :confused:

My $.02 FWIW..... :coolman:

Marauderjack :bandit:

metroplex
04-11-2005, 05:47 AM
Center wear = overinflation
Outboard wear = underinflation

Continue dropping the pressure until you observe even treadwear.

the max sidewall rating for your BFGs is 44 psi IIRC. That means using the 75% rule, you fill to 33 psi cold.

How are your front tires wearing at 33 psi? You can adjust camber and toe to fine-tune the inboard/outboard wear.

For the rears, try lowering the pressure... or just get new tires. Ditch the BFG crap in the garbage.

Alan
04-11-2005, 10:20 AM
My MM is at the dealership right now getting new rubbers in the rear. Center gone on both at 16K miles and I go easy on her. I've been running 32/32psi on my 2003...just what the door sticker shows...but replacing those rears every 15-16K is gonna hurt a little.

metroplex
04-12-2005, 03:59 AM
If you have a pyrometer (spelling? checks tire temps), start dropping the rear tire pressure BUT keep monitoring the sidewall temps. If you start to see even treadwear at a low low temp, compare the sidewall temps. If the sidewall temps are significantly higher than the fronts, bump up the pressure.

How much is the difference in treadwear between the center and the outboard/inboard edges of the tread? If it's within 1/32"-2/32", I'd say it's about 1-3 psi difference.

FordNut
04-12-2005, 04:34 AM
I ran my first set at 32, wore out the middle in about 15k.

Second set at 28, wore out the middle in about 15k.

Third set at 38, wore out the middle in about 22k.

I would like to see what 42 does for me, but I'm changing to widened rims and Eagle F1s.

Emipirical data tells me more than theoretical explanations.

metroplex
04-12-2005, 05:37 AM
Emipirical data tells me more than theoretical explanations.

Yep, those bling bling 18" tires suck for treadwear.

Alan
04-12-2005, 08:00 AM
FordNut,

Your post intrigues me. Conventional wisdom says that center wear like we're experiencing would dictate a need for lower pressure. Looks as if you tried that and wore them out at the same rate. However, increasing the pressure in your tires to 38 yielded more mileage.

I seem to recall a post somewhere above that seemed to touch on this phenomenon. It's all bass ackwards...but I'll try anything to prolong the life of those rear tires.

I think I'm going to try 42 psi this time around.


I ran my first set at 32, wore out the middle in about 15k.

Second set at 28, wore out the middle in about 15k.

Third set at 38, wore out the middle in about 22k.

I would like to see what 42 does for me, but I'm changing to widened rims and Eagle F1s.

Emipirical data tells me more than theoretical explanations.

Rat
04-12-2005, 11:19 AM
Alan better try 42, 38 sure is not working for me and I have the same size on all 4 corners and rotating evey 3k.
I have tried from 28 to 38 and it doesn't seem to make any noticeable difference what I do. I think that it has to be something in the tire composition. One thing about it the old style BF's are cheap. I would like to know if the dudes that have changed brands are having the same problems.

Bob


FordNut,

Your post intrigues me. Conventional wisdom says that center wear like we're experiencing would dictate a need for lower pressure. Looks as if you tried that and wore them out at the same rate. However, increasing the pressure in your tires to 38 yielded more mileage.

I seem to recall a post somewhere above that seemed to touch on this phenomenon. It's all bass ackwards...but I'll try anything to prolong the life of those rear tires.

I think I'm going to try 42 psi this time around.

Alan
04-12-2005, 11:26 AM
Rat,

That's clear. Thanks!


Alan better try 42, 38 sure is not working for me...

MENINBLK
04-12-2005, 12:46 PM
Alan better try 42, 38 sure is not working for me and I have the same size on all 4 corners and rotating evey 3k.
I have tried from 28 to 38 and it doesn't seem to make any noticeable difference what I do. I think that it has to be something in the tire composition. One thing about it the old style BF's are cheap. I would like to know if the dudes that have changed brands are having the same problems.

Bob

I am running 40psi in my rears, and 38psi in the fronts.
I've only got 2k on them so I can't really tell you if its working yet.
My first set of rear tires I changed out at 20k and they had .2" center tread left on them.
I was running them at 40 also...

Marauderjack
04-12-2005, 02:21 PM
44 PSI all around will get you optimum mileage if you can stand the ride....actually it ain't too bad!!! :burnout:

Whoever was arguing about lowering the rear pressure...take it from me....my first set was gone at 7K miles with 24 PSI!!! Go for it if you don't want to listen to experience?? :confused:

My second set went 33K miles at 40 PSI and now I'm up to 42-44 PSI to see what happens!! :beer:

Marauderjack :bandit:

TechHeavy
04-12-2005, 03:24 PM
44 PSI all around will get you optimum mileage if you can stand the ride....actually it ain't too bad!!! :burnout:

Whoever was arguing about lowering the rear pressure...take it from me....my first set was gone at 7K miles with 24 PSI!!! Go for it if you don't want to listen to experience?? :confused:

My second set went 33K miles at 40 PSI and now I'm up to 42-44 PSI to see what happens!! :beer:

Marauderjack :bandit:
Could a pattern be developing here?? I've been at a constant 40psi all around and am approaching 28,000 miles with decent tread left, (minus the evaporating of rubber on the rears after the Trilogy, but still ok). :D

Alan
04-12-2005, 03:38 PM
7K?!? Okay...I hate to say this because I don't want to make you feel any worse than you already do about that, but DANG, I thought replacing my rear tires at 16K was bad!


....my first set was gone at 7K miles with 24 PSI...

metroplex
04-13-2005, 05:02 AM
If you're getting optimum treadwear filling to the max sidewall pressure - then the tire size is wrong for your application or your chassis needs tuning (weight shifting, etc...)

because I checked Tirerack and your BFGs have a max sidewall pressure of 44 psi (cold). I saw your stock tires in action at the track and I'm not impressed at all. There are better and less expensive tires, but probably not available in bling bling 18" sizes. None of the BFG tires have yielded optimal treadwear and performance for their price. They're only good for drag radials.

I'd probably look into figuring out a way to swap to 2003-up LX Sport 17" wheels for better tire options unless there are better 18" tires available.
Just my 2 cents...

TAF
04-13-2005, 06:01 AM
I'd probably look into figuring out a way to swap to 2003-up LX Sport 17" wheels for better tire options unless there are better 18" tires available.
Just my 2 cents...
Uh....I'll pass....





None of the BFG tires have yielded optimal treadwear and performance for their price. They're only good for drag radials.
Wrong....

Click HERE to learn more about the NEW BFG's (http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+T%2FA+KDW+2&vehicleSearch=false&partnum=555VR8GFTAKDW2RF&fromCompare1=yes)


http://www.tirerack.com/images/tires/bfg/bfg_gforce_ta_kdw2_ci2_l.jpght tp://www.tirerack.com/images/tires/bfg/bfg_gforce_ta_kdw2_ci1_l.jpght tp://www.tirerack.com/images/tires/bfg/bfg_gforce_ta_kdw2_ci3_l.jpg

metroplex
04-13-2005, 06:21 AM
Uh....I'll pass....





Wrong....

Click HERE to learn more about the NEW BFG's (http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+T%2FA+KDW+2&vehicleSearch=false&partnum=555VR8GFTAKDW2RF&fromCompare1=yes)


http://www.tirerack.com/images/tires/bfg/bfg_gforce_ta_kdw2_ci2_l.jpght tp://www.tirerack.com/images/tires/bfg/bfg_gforce_ta_kdw2_ci1_l.jpght tp://www.tirerack.com/images/tires/bfg/bfg_gforce_ta_kdw2_ci3_l.jpg


Uh... I'll pass. They're most likely noisy and wear down fast. At $131/tire, I'll pass for sure. I just bought new Kumho summer tires for less than $300 shipped, mounted, balanced, and installed on my Vic. Bling bling 18" tires are expensive in comparison. You have staggered tire sizes and if you get directional tires, forget about tire rotation. That's one additional item killing the treadlife. Just my 2 cents. I'll take function over form.

My Dunlop SP Sport 5000s weren't too bad when I bought them 5 years ago ($80/tire). They were great until the last 2/32"-4/32" of tread - no hydroplaning, great wet traction, OEM Lincoln quiet, great dry handling, and I drag raced the schitt out of them (Hack has a video of me drag racing Trilogy 1 doing a large two-wheel burnout at the start, unless he didn't capture that part).

I don't have bling bling 18s so I didn't do any research on your tire options. I'd veer away from BFG unless they changed big-time. Their tires used to sell on because of their name. Function over form.

TAF
04-13-2005, 06:29 AM
Yeah...it's a lot different putting tires on a 16 second CV that handles like a boat.

You made the right choice for yourself. :up:

FordNut
04-13-2005, 06:33 AM
Uh... I'll pass. They're most likely noisy and wear down fast. At $131/tire, I'll pass for sure. I just bought new Kumho summer tires for less than $300 shipped, mounted, balanced, and installed on my Vic. Bling bling 18" tires are expensive in comparison. You have staggered tire sizes and if you get directional tires, forget about tire rotation. That's one additional item killing the treadlife. Just my 2 cents. I'll take function over form.

My Dunlop SP Sport 5000s weren't too bad when I bought them 5 years ago ($80/tire). They were great until the last 2/32"-4/32" of tread - no hydroplaning, great wet traction, OEM Lincoln quiet, great dry handling, and I drag raced the schitt out of them (Hack has a video of me drag racing Trilogy 1 doing a large two-wheel burnout at the start, unless he didn't capture that part).

I don't have bling bling 18s so I didn't do any research on your tire options. I'd veer away from BFG unless they changed big-time. Their tires used to sell on because of their name. Function over form.

Your suggestions on tires may be applicable to the CV, but are totally wrong when applied to the MM. We have stock 18" tires. We have a PCM which will not allow the ABS and TC to work properly unless we have staggered tire sizes. $131/tire is the norm for us. Obviously you have offered advice without doing your research.

TechHeavy
04-13-2005, 12:38 PM
Your suggestions on tires may be applicable to the CV, but are totally wrong when applied to the MM. We have stock 18" tires. We have a PCM which will not allow the ABS and TC to work properly unless we have staggered tire sizes. $131/tire is the norm for us. Obviously you have offered advice without doing your research.
Thank you FordNut. Well said.:2thumbs:

MENINBLK
04-13-2005, 12:49 PM
If you're getting optimum treadwear filling to the max sidewall pressure - then the tire size is wrong for your application or your chassis needs tuning (weight shifting, etc...)

because I checked Tirerack and your BFGs have a max sidewall pressure of 44 psi (cold). I saw your stock tires in action at the track and I'm not impressed at all. There are better and less expensive tires, but probably not available in bling bling 18" sizes. None of the BFG tires have yielded optimal treadwear and performance for their price. They're only good for drag radials.

I'd probably look into figuring out a way to swap to 2003-up LX Sport 17" wheels for better tire options unless there are better 18" tires available.
Just my 2 cents...

Why do you bother coming to this site ?
Do you ever READ anything we post ?
I've made many posts on this issue, and I've even put a link back to the BF Goodrich Forum
where a BFG Tire Designer/Test Driver discussed the issues with our tires.
BF Goodrich Forum (http://www.bfgoodrichtires.com/bfgapp/servlet/Controller/site.forums.LoadMessages?discu ssion_id=.1dcec03a&topic_id=.1dce8370)

Other members have posted their own experiences,
and the results they have gotten by altering their own tire pressure.

Tirerack didn't MAKE the KDWS tires, all they do is SELL them.
Most people aren't impressed with the KDWS on the track because they are STREET TIRES !
And you are trying to take an application for a vehicle,
which is very different than yours,
and modifying your own vehicle to make it fit.
IT WON'T WORK !

If you can't understand what we are stating,
and can't understand what we are writing,
then don't bother posting something that already has been discussed,
because all you are doing is beating a DEAD ISSUE !!!

Canadasvt
04-14-2005, 07:44 AM
I only have 2000km on my MM, but thanks to this thread I think I'll up the psi to 35/40 and report on it later in the year.:beer:

Marauderjack
04-14-2005, 02:39 PM
Canadasvt....

What in the heck is that stuff on the car in your avatar?? :confused:

Never saw that before down here!! :D ;)

Marauderjack :cool:

SILVERMARAUDER
04-15-2005, 08:02 PM
There is a post at the BFGoodrich Forum.
BF Goodrich - KDWS Center Wear ??? (http://www.bfgoodrichtires.com/bfgapp/servlet/Controller/site.forums.LoadMessages?discu ssion_id=.1dcec03a&topic_id=.1dce8370)

The simple explanation is that we need an extra 5 - 7 lbs of pressure
on the DRIVE AXLE because the KDWS we use are WIDER,
and because our cars are considered high horsepowered....

The Pontiac GTO also suffers from this problem.
They run a very wide 17" KDWS and have accelerated center wear.

good info thanks guys!