Cupping after 7,000km and dealership doesn't know why

Boy, I sure hope someone can help me out here. I just dropped 2500$ on some 255/85r16 Cooper St Maxx a few months ago and now I'm dealing with some mild cupping and they only have 7000km on them.

Body shop first pointed it out to me and dealership confirmed it. Have a slight vibration in my seat so it's mostly my rear tires; front as well but not as bad. Took it to the dealership and they said my OEM suspension, balljoints, ect is all fine.

They won't do a balance or alignment because they say it won't do me any good and some kind of liability mumbo jumbo. Their master technician will take a look at it Monday but I'd like to have some pointers in my pocket when I have a conversation with him.

Was running 35psi up front and 32 in the rear.
What could be causing this?
What are my options here? Are they just a waste of 2500$ at this point or is there someway I can still get some use out of them?
I don't have any pictures because it's sitting at the dealership for the rest of the weekend and tbh I can't physically see anything when I looked.

 

That is a very aggressive tire. Goodyear and Firestone MT tires always cup unless you incessantly cross rotate them before the cupping gets severe.
If all the variables check out you just may need to invest in a cross rotation every 5K.

 

Dealerships are hit or miss. Find an independent shop.

 

Agreed. Unfortunately the only independent shop that's any good is a 5 week wait

 

If they won’t do an alignment, they’ve already done one? If not, then they don’t know until they put it on the rack and hook everything up (at which point, you paying for an alignment). If they did, post the results, there’s some here that know the numbers and have specific adjustments.
Be sure to also include any and every specifics you can too: lift, tires size, wheel spacers, aftermarket wheel specs, etc

 

Thanks, I'll get em to do it on Monday. According to google I'm going to die in a fiery accident if I drive on cupped tires. Is there going to be any damage done to my truck if I try to get more life out of these tires?

 

They havent done an alignment, they said it wouldnt do any good, but I'm going to make them do it on Monday anyway. When I get those numbers I'll definitely post them up here

 

Resident techs feel to chime in here, as I am NOT one-
If they haven’t put it on a rack and measured, they simply don’t know. One can’t tell just by looking at it in the parking lot.
Also; why did it go the body shop? A wreck can cause issues if damaged frame and/or suspension components.

 

100% correct. While you can visually decide if you need an alignment looking at a tire that’s half worn, there’s no way you can make that decision on a fairly new tire.

 

Somebody hit my tailgate. There's no frame damage, I had the shop local to me check everything over. I trust their assesment on that they're pretty good. Suspension damage (or wear) was my suspicion as well, that's why I had the dealership check it out.

 

Check alignment
Have tires road force balanced by a competent shop

 

Book the appointment. 5 weeks will go by. Tire shops specialize in tires, alignment, balancing and brakes. Dealers know little about tires, alignment and balancing. Those things are just a bother to them and often they just take your vehicle to a tire shop. I know as I have been in tire and trucking industry

 

You might also think about doing the chalk test on your tires and see exactly what pressure they’re asking for

 

Lol what? Just keep driving. https://www.bridgestonetire.ca/learn/maintenance/tire-cupping/

Can you actually see the cupping/feathering on the treads aside from what the body shop is telling you? Might be lost in the wash when every other tread block has a corner missing by design:



There are a few things you can try/do:
Rotate your tires more often.
Get your tires rebalanced at a different shop.
Experiment with lower tire pressures such as 30 psi front and 28 psi rear.
Replace your shocks with better ones if they have more than, say 40,000 kms on them.

 

A quick google shows this. Under inflation or over inflation may cause cupping too. https://www.bmwatlanticcity.com/wha... or over-inflated,other forms of uneven wear.

 

With aggressive tires like that they're gonna cup like that especially fast compared to standard street tires. Provided the tire pressures are correct then your toe angle plays the biggest part in that wear and it's a very very fine line/compromise between good road manners and minimal tire cupping. I can't give you spec exactly because typically when I align a vehicle I fine tune adjust toe on the road to perfect it and I do it by feel. The easiest way to explain it is essentially too positive a toe setting will make the vehicle drive straight but add a "delay" to the steering, whereas too negative a toe setting will make the vehicle wander and be very squirrelly with steering inputs. Both to a point of course. The sweet spot to avoid rapid wear is the most minimal amount of toe in where the steering is responsive but the vehicle tracks straight. It can vary from vehicle to vehicle depending on how much deflection suspension components have, weight of the vehicle, tires, camber/caster, etc. an alignment can help if your guy knows alignments well. Ultimately though you need to cross rotate your tires far more often. At the end of the day aggressive tires like these were not made for high speed driving so but running them as everyday street tires they're gonna cup especially fast, you can do a few things to slow that wear but tire rotations like clockwork are the only thing thats really gonna keep the wear somewhat in check with off road oriented tires

 

Duratrac wrangler good years, rotated 3 times now @ 8,000 miles they’re just now getting loud a bit. Front 42psi rear 35-40psi
I have a little cup action too. Normal

 

My duratrac is loud as hell . Cupping too.

 

Not every tire likes the same psi as your previous tires.

Look up the chalk test.

 

Learned this the hard way. Mine started cupping at 10k and I didn’t expect that so fast. The tires are rotated every 5k. Drives me nuts and I’m have 25,500 on them. Falken wildpeak 255/85/16s. I’m seriously debating getting new tires but not sure. The last rotation helped out and the vibrations have diminished. I’m going down to 265/75/16s next.