Tires Cupping. A Few ?'s

So I have 3rd-gen TRD OR Bilsteins on my '14 2.7. I drive a lot of highway, about 100mi + M-F. I have been running Dynapro A/Ts, which I will be replacing before winter. I have done my best to keep them rotated but have noticed that they show signs of cupping (I guess). Like every other tread is worn on the outer edge. It isn't very noticeable, but still something I have kept an eye on. So When I swap tires here in a month or so, I also want to have an alignment. But is there anything else that is wrong. I had the truck checked over for my inspection / last tire rotation in July and the shop said everything checks out perfect. I just didn't know if anyone else experienced it, especially if they drive an unusual amount of highway, like I do. If I can prevent it from happening on the next tires, that would be great. FWIW, I have gotten great life out of these Hankooks and they are otherwise worn even across the board. I am pleased with how long they lasted.

 

My truck started doing that at about 125,000 miles. I ended up needing new shocks. I had them replaced before buying new tires and it fixed the problem.

 

Shocks is probably a first check. Unless you have directional tires, always cross rotate

 

Pretty much every AT tire i have seen will cup or wear the different size lugs differently. My cooper AT3's are doing that. My hankook dynapro atm rf 10s did it BAD, just a product of the design.

 

OK cool. Thanks for the responses, guys. I'd like to think that the shocks are still in good shape, so hoping that it is not that. I will swap my BFG's on in a month or so, get it aligned and just keep an eye on the wear. But if it seems to be a problem to the point of premature wear, I'll look into new shocks again.

 

Good thought process there!

 

Probably NOT the shocks.
Probably what it is, is the alignment.
*BUT*, that doesn't mean that the alignment is wrong. You see, roads are built such that they slope down to the right. This is to allow water to pour off the road. In order for a vehicle to track straight along a road that leans to the right, the front tires are set to lean a bit to the left. Its called "camber". I bet you that you see the cupping mostly in the front driver's side tire, correct?

 

caster differences do a much better job at accounting for road crown without the negative effect of wacky tire wear.

 

Not so. And this, as you call it, "wacky tire wear" is not generally pronounced, but rather extremely gradual, over tens of thousands of miles.

 

Does your truck feel out of alignment? If it doesn’t you probably don’t need an alignment.

If you have 100k on your struts OR do hauling and towing with your truck and have around 80k on them you may be due for new ones.

Tires should not be cupping.

 

have the alignment checked by a professional, usually they will check it for free

 

Cross rotate? I always thought it was front to back, same side for RWD vehicles.

 

Nah, he's right. You want to offset Caster to deal with road crown. Setting the camber to the opposite direction of the pull from road crown will result in extremely pronounced wear on the left edge of the tires, and general instability because you're not having your whole tire on the ground. Whereas if you have the passenger side tire have slightly more caster it will make the truck tend to drift a little into the crown (i.e. track straight) without sacrificing contact patch.

 

After my Coopers AT3`s were cupping bad. I started Cross rotating them ( from tire guys reccomendation) seemed to stop. On my New set of Falken`s WP , I will only cross rotate.

 

Good to know. So basically running them backwards to correct it?

 

Tires should always be rotated so they end up on every corner and run in both directions. Other than tires that have directional tread I've never seen anyone do it any other way. I've always used pattern A.

I'd still check shocks. That is the number 1 reason for cupped tires. Alignment is a possibility, but I'm still betting your shocks are gone. What ever it is I wouldn't buy new tires until the problem is corrected. Once you buy new tires and uneven wear starts it is harder to stop.

 

My Cooper AT3s were cupping, 06 TRD OR. Installed new Bilstien 5100s and and new ball joints (in SPC arms which failed) and then the cupping stopped. It was the wore out shocks and ball joints causing the cupping.

 

I had a major cupping issue come up on my Duratracs after 38k ish miles. I had an alignment check, all good, rotated tires to 'correct' and ran 2k more miles before going to new Cooper AT3 4s. Smooth, smooth ride now (changed size to 255/70/r17). This weekend I am replacing shocks to 5100s to mitigate any unseen issue.

FWIW, Firestone did tell me that since the alignment was 'perfect' it was probably something in the suspension.

 

With the stock TRD suspension my stock Rugged Trail tires cupped at 30k miles even with regular alignments.

With the Icon Suspension my Duratrac tires cupped with right around the same mileage. I got a 50% pro-rated credit from Goodyear towards another set of Duratracs because they deemed the cupping was a defect.

With the history of my truck I think they will cup again when the tires have 30k miles on them.

 

I’ve read you should only rotate front to back. Not to cross sides.