Front tire cupping

[JohnVickrey]

The right front tire is cupping along the outside edge.  What causes this??  It's a 4104 wearing Bridgestone R250  11.00/22.5R. 

[bevans6]

When I had that on a van, it was shocks that were bad.  I found that once the tires were cupped there was nothing to do but put up with it or replace them, and hope like heck that what you changed actually fixed the problem.  All sorts of worn out parts or bent stuff can cause cupping.  You could always rotate the fronts to the duals, if they are the same type of tire.

Brian

[JohnVickrey]

I suspect the shocks but only one side is cupping.....

[bevans6]

Maybe only one shock is bad?  The idea is that the tire starts a high frequency hopping motion that the shock doesn't control so it starts to wear the cups.  Once they start they are self perpetuating, they make themselves worse.  My van was a brand new Chevy 3/4 ton, 2000 model year.  The shocks were completely worn out in 5,000 miles and the front tires cupped at about 15,000, I had to get them replaced at my own cost.

The problem is that it can be many things, apparently.  In my case the van (worst purchase decision I ever made on a vehicle) was basically brand new, just had crap shocks.  At first I only replaced the rears, because the back of the truck was hopping around so bad.  I should have replaced all four.

Brian

[papatony]

Out of alignment and/or out of balance will also cause this.

[white-eagle]

out of balance will also cause this.

so you should move to right and let Lois drive.  

seriously, i'll be you've been pushing too much sand and got yourself some alignment issues while making some turns.  But with all the stuff you carry, could be out of balance or even overloaded?.  

[gus]

When I have a tire doing this I move it to the rear once the problem is solved.

[JohnVickrey]

I moved it to the rear.  We'll see how it goes......   

[luvrbus]

On a bus check

camber

drive axle alignment

king pins

bearing adjustment

heavy load on the cupping side

air pressure

got this from the best front end shop in the business Dick Kaiser of Eugene Oregon I never heard of shocks causing cupping on the outside edge with a 11R/22.5 tire learned something

[JohnVickrey]

I don't know if the shocks will cause cupping either.  I checked the bearing and king pin and it seems normal.  Lois sits on that side maybe that is the problem.  

[buswarrior]

This guy here, best we all say a prayer for him.

Dead busnut walking.

If she doesn't read the boards, someone else's significant other will tip her off, because, that's just how it works...

Been nice knowing you John!

happy coaching!
buswarrior

[artvonne]

http://www.procarcare.com/includes/content/resourcecenter/encyclopedia/ch25/25readtirewear.html

[luvrbus]

www.bridgestonetrucktires.com has good info for bus and truck owners tire wear, the comment about the passenger I am not going there John you are on your own lol

good luck

[bevans6]

http://www.bridgestonetrucktires.com/us_eng/answers/doctor_wear.asp#2

Cupping and right front outer edge wear is almost the most common question!

Brian

[white-eagle]

http://www.bridgestonetrucktires.com/us_eng/answers/doctor_wear.asp#2

Cupping and right front outer edge wear is almost the most common question!

Brian

So there you have it!  The graded slope of most roads along with Bridgestone tires is an issue.    I don't have any cupping (knocking on wood) on my goodyears. yet.
come to think of it.  i did have some cupping on my right inside dual a couple years ago.  i later found i had been driving on low air.  Yeah, yeah i know, but it was hard to check, etc.

Sorry John, Fran saw the thread.