Harder to diagnose an IFS tire cupping issue. Warn out shocks will not cause cupping. Check all steering components for slop (steering box) and all the bushings and ball joints.

You may need a steering stabilzer in there to control the larger tire.

Are you sure?

I've found bad shock will cause cupping, they allow the tires to bounce.

Maybe I've been wrong all these years, but I'm willing to learn something new.

You're not wrong Michael.

From what I understand the shock absorber is controlling the rate of motion not the geometry of the motion itself. I had dead shocks on my solid axle Ford front axle and it caused no cupping or un-even wear beacause the tires relationship to the ground is controlled by the ball joints and steering linkage.

With the IFS setup the geometry of motion is controlled by the ball joints, steering linkage & a-arms so I do not see how a tire going up and down is going to cause cupping. I beleive cupping is due to geometry issues only. If the steering linkage is causing the tire to be pushed in and out as the suspension cycles up and down then the shock absorber may reduce the cupping effect but the root cause is still the geometry or wrn out parts causing the tire to fail in and out.

Thanks for all the info, let's kill this thread and move on. I have the stock tire and rim package for an SR level Montero, that is, 31" tires, 15" alloy rims and 4.88 gears from Mitsu <img src="/forums/images/graemlins/cheers.gif" alt="" />. I think the control arm bushings are probably at fault and will recheck them this week. As for weak shocks and cupping, yes I really agree, worn struts and shocks can contribute or allow cupping to happen.
Thanks again for all the inputs and posts, it's rare that I get stumped by my own truck, but we've all been there. <img src="/forums/images/graemlins/kewl.gif" alt="" />

FYI...



web page

Kevin

Perfect, Kevin! <img src="/forums/images/graemlins/cheers.gif" alt="" /> That explains it exactly.

Edward