blank87

Guys I noticed my front tires are starting to cup pretty bad. Im gonna start looking for worn bearings all over my front end tomorrow and get my alignment checked but I was wondering if any of you guys have heard of certain bearings that are a constant problem? I just want to hopefully skip a step and just check something that is more of a common problem first. Thanks guys...

huntingman2706217

what do you mean by cupping? center tire wear? outer tire wear? only one side wears? or every other tread wears?

finneys98xj

rotat your TIRES. every oil change when you run a mt or at

blank87

I have mickey thompson mtz tires and they are only wearing in the middle. And its a weird kind of wearing pattern cause its there is a 1/8" depth difference between each **** on the tread pattern going down the middles. And on the mtz's each **** is about 1"X1.5" so its very noticeable.

Mike1998XJ

I believe that the toe-in is incorrect if you have cupping. Have it aligned...

huntingman2706217

if there only wearing in the middle the you have them over pressurized causing the center to bulge out more then the sizes... if the tires was under inflated the sides would wear faster then the middle... i dont know what these other guys are talking about... thats why i needed a better explanation... if you set it at max psi then thats probly to much... hints MAX psi... try 5 or 7 psi less then the max... goodluck!

huntingman2706217

toe in would cause the inside of your tires to wear faster then the outside... because th tires would point like this.... / \... and they would fight each other to the center... causing death wobble and everything else... tow out they woud point like this... \ / ... and then the outside of the tires would wear and they would fight each other and cause the same problems... both will also kill your suspension joints... there is no angle that wil cause the center of the tires to wear... only tire pressure...

blank87

all of my tires have the same pressure and its only my front tires that are showing the wear

Firestorm500

Cross-rotate all 4 tires every 5000-7500 miles to equalize wear.

Have toe-in checked pretty soon.

thelaststarfighter13

The front of your vehicle and the back don't weight the same. Especially if you tow. You need to adjust your tire pressure. Also your front tires will show more wear quicker with the wrong tire pressure. Consider that they are doing all the steering and most of the braking along with the weight of the engine on them.

Tire pressure.

Firestorm500

He should be running betwen 30-35 PSI cold front and rear.

Same pressure in all on a Cherokee.

Firestorm500

In addition he might have bad or weak front shocks.

Mike1998XJ

I pulled this off the net... You have it backwards... Toe in causes wear or cupping on the outside edge of the tires as I said.
Mike

For minimum tire wear and power loss, the wheels on a given axle of a car should point directly ahead when the car is running in a straight line. Excessive toe-in or toe-out causes the tires to scrub, since they are always turned relative to the direction of travel. Too much toe-in causes accelerated wear at the outboard edges of the tires, while too much toe-out causes wear at the inboard edges.

huntingman2706217

yep your right... i had it backwards... but its still not as you said either... hes got ware in the middle of the tires... not the outside or inside... So toe has nothing to do with it unless its worn so much on the outside or inside that its all the way to the center... i mean i could be wrong but i worked at nissan as a tech and thats how the alignment machine explained it... so i guess its right anyway?

Mike1998XJ

Yes, I reread his second reply and I see he changed his tune from cupping to a center wear issue which should be overinflation as someone said. I wish people would always post pictures... Or at least google a little information so they are sure they are describing their problem in correct terminology.