kjcole

Changing front shocks on '02 with 90K miles. Not leaking and seem to be controlling rebound but finding my front tires Eagle f1 Gs-D3 (yes, a soft summer tire) were cuppng badly and quickly across the entire face of the tire. Rotate to back and they round back (so I don't suspect balance issues). Can't find anything worn in the front suspension so I'm going for the most likely suspect, the shocks. Have KYB G2's coming. While I"m under there should I consider putting new upper control arms (with bushings/ball joints) even though they feel solid, look good, and no noises from the suspension?

Thanks

iolmaster

iTrader: (1)

Cupping is not normally the struts. Have the alignment checked.

tentoys

mine were cupping so i installed Megan EZ coilovers, rotated tires and had it aligned. Problem gone.

kjcole

Hmm. It's been my understanding that cupping is usually from vertical bouncing of the tire from worn suspension (often shocks) or wheel balance (the two major things that will cause or allow the tire/wheel to bounce) rather than alignment. In any case, since everything else is tight I've decided not to change anything else, just the shocks, and of course get a full alignment and balance with the new tires.

iolmaster

iTrader: (1)

May be we are not talking about the same symptom.

kjcole

"cupping" is also called scalloping. Basically the tire develops high and low spots at regular intervals. Somethings only on the edge, but in my case more across the face.

iolmaster

iTrader: (1)

Then we are talking about the same thing. My understanding that cupping or scalloping is an alignment issue when it is on the edge.

kjcole

OK. Cupping on mine is across the middle of the tread. Severe scalloping rather than a feathering. 90K miles so probably needs shocks anyway.

jzwu

Cupping is usually caused by suspension/shocks. Alignment issues usually cause tire uneven wear.

scdroptop

iTrader: (1)

Cupping could also be just alignment or bends in the rim or even an out of round tire from sitting, causing dead spots in the tires so they hop...I'd be surprised if you need new shocks. May be tie rod related as well.