What causes tire cupping? 96 Camry

[jamesm113]

What can cause tires to cup? I'm working on a friends 96 Camry LE with stock 195/70R14 steelies.

Under inflated?
The tires were at 20-22psi

Out of alignment?
The outside of the rear tires were worn a lot extra.

Worn suspension?
The rear struts are a little looser than i'm used to. I think they are also originals too. They don't bounce like

this guys struts

this guys struts

but they aren't as solid as my subarus either.

Crappy tires?
They are geo star tires, which I've never heard of.

Out of balance?

Anything else?

The car has 260k so I don't want to replace the struts unless it needs them. Also the front tires (although newer) are not cupping and the struts are just as bouncy.

I'm going to get the alignment checked fixed and make sure the new tires are properly inflated.

[carsrus]

Crappy tires can cause weird wear. Under inflation to a point as well, but it would have to be severe and for a long time.

Does it pull to one side? Loose steering?

If rears are cupping maybe rear lateral control arm. Struts in general dont cause weird wear. Mines are pretty shoddy in the camry and tire wear is excellent.

Some crappy tires are hard to balance since they might be out of round/ tread separation. Wont cause weird wear but the weird wear will kill the balance.

[fenixus]

under-inflation will cause more wear on sides of tire as opposed to center wear (over-inflation).

Tires can be cupped because of bad struts... primary function of strut is to keep tire pressed to ground ... driver comfort is merely a secondary function (and rather more depends on springs than struts themselves)...

original rear struts at 260k are there probably for decoration only, as they do not meet any specs at all ... generally any bounciness means the strut is done. there should be absolutely no bouncing at all, car should do only one swing in every corner, no more if struts are good.

cheap tires can be more prone to cupping even if suspension is more or less good.

rockauto sells cheap Monroe QuickStruts.
there are even cheaper options on ebay (USS parts or something like that), not Monroe though, but something similar.

[sam333]

Cupping ( bad struts , out of balance tires make it worse) Tires are expensive, its not worth having bad struts.

[capnblinski]

The tires were at 20-22psi

psi too low. always to be best in the following of the tire manufacturers recommendations. lol.

[JohnGD]

Check Michelin's tire guide on tread problems:

http://www.michelinman.com/tire-care...is/tread/cups/

Check alignment, balance, and suspension components.

[jamesm113]

Crappy tires can cause weird wear. Under inflation to a point as well, but it would have to be severe and for a long time.

I'm sure it was a long time. Long enough for the tires to get down to 20-22psi from 30psi...

Does it pull to one side? Loose steering?

I actually didn't test drive the car. The tie rods were sturdy when I checked them out though. Not sure if it pulls to a side or not, but I think the camber was definitely off in the rear wheels.

under-inflation will cause more wear on sides of tire as opposed to center wear (over-inflation).

Well the insides of the tires are fine... it's just the outsides that are extra worn.

If rears are cupping maybe rear lateral control arm

How can i check the rear lateral control arm?

Cupping ( bad struts , out of balance tires make it worse) Tires are expensive, its not worth having bad struts.

Well, both the tires still had wheel weights on both sides.


So I guess my main question is, on a car with 260k, is it worth replacing the rear struts? Or would just replacing the tires with quality & balanced tires (I think we're looking at Michelin X-Radials and Kumho KR21s right now), getting an alignment, and making sure the tires are properly inflated in the future be enough?

I think it's going to be $200-230 for the tires, $70 for alignment (these cars require a 4 wheel alignment right? it's $50 otherwise), and then I found monroe struts for $50/piece on amazon. I would probably need to get the spring compressor too.

If I end up replacing the struts, would I need to replace the strut mount or spring coil or anything else? Or do only the struts affect tire wear?

Thanks so much for your help!!

[JohnGD]

Tires are getting expensive these days. I'd go with Michelin.

If the struts are weak and was responsible for the cupping, then the new tires will become cupped too. QuickStruts are available, and about $125 each plug shipping a very good deal on rockauto. It's better to get the QuickStrut than buying individual components, which will often cost more.

Also, an alignment shop should be able to tell you the condition of the control arm bushings and rear links.

Originally Posted by jamesm113

So I guess my main question is, on a car with 260k, is it worth replacing the rear struts? Or would just replacing the tires with quality & balanced tires (I think we're looking at Michelin X-Radials and Kumho KR21s right now), getting an alignment, and making sure the tires are properly inflated in the future be enough?

I think it's going to be $200-230 for the tires, $70 for alignment (these cars require a 4 wheel alignment right? it's $50 otherwise), and then I found monroe struts for $50/piece on amazon. I would probably need to get the spring compressor too.

If I end up replacing the struts, would I need to replace the strut mount or spring coil or anything else? Or do only the struts affect tire wear?

Thanks so much for your help!!

[TheJourneyman]

Don't get an alignment until you've found out or decided if you are getting suspension or steering work done first. If you do get suspension or steering parts replaced, you'll need an alignment afterwards, so doing one now is a potential waste of money.