Tires cupping

This is my second set of tires cupping after about 20k miles. Rotated every oil change at 5k.
Everything with the suspension feels tight.
Bilstein 5100s have about 60k miles on them now but still seem to be good. Any advice or possible solutions? How many miles can I expect out of these shocks?

 

Alignment?

 

Have the alignment checked and make sure it is within specs especially if you have a lift.

 

Alignments been done twice. Both times they tell me it was within spec but had them do it anyway

 

Ibhave 5100s set at 1.75

 

Cupping is only the inside shoulder on both front tires. I have bfg ko2s fwiw.

 

I have noticed grease around my ball joints.
Is this normal over time or should I replace them? I've jacked the front up and tried to wiggle the tire in all directions but all feels tight

 

Did they give you a printout from the machine?

"In spec" and "good" aren't always the same thing.

 

Cross rotating will help but if they have already started cupping.. you might just help to not get worse.

 

Any reputable alignment shop should tell you right away if there were issue's with any components that would affect your alignment. If not find another shop.

 

If it were my vehicle I would check:

1) alignment - camber and toe can add to this wear. As stated above, in spec doesn't mean it won't cause wear. The shop should set your air pressure and check components before performing the alignment.

2) shocks

3) tire balance - a lot of shops just don't do a great job on this one. Make sure it's dynamically balanced if you do a lot of street driving

4) worn out parts (BJ's and bearings)

5) driving style - agressive cornering can amplify any of these issues

 

Engage your locker, do 6 to 8 very long smokey burnouts, swap tires to front, repeat burnouts till they are no longer cupped. Almost like new now. Good luck.

 

Cupping is a good indication the shocks aren't working right. Shocks can go bad at any time, and if your lifted sooner. My factory shocks lasted a bit over 110,000 miles before my tires started cupping. All 4 were cupped exactly the same so it was pretty obvious they were rotated properly I just dealt with the cupped tires until they wore out. They were louder. But made sure my shocks were replaced before buying new tires.

 

I have a question he has Bilstein 5100's they have a lifetime warranty. Since other than leaking the only way to check a shock is working properly is a shock Dyno. Will Bilstein test and replace his shocks if he sends them in? Has anyone done this with them before? How is Bilstein to work with on warranty issues?

I also am running Bilstein 5100 and my KO2's are cupping.

 

Cupping is usually due to high tire pressure..
Center wear(cupping) to much air and worn edges are due to under inflation

Go back to old school and chalk the tires.
-Get sidewalk chalk and draw a 2-3 in line across the tires
-Drive 20 or 30 feet and see if the chalk mark is wearing even..
-let out air and repeat until the wear is even.

 

I was wondering if I was slightly under inflated. The door plate in drivers door jamb says 29 lbs of air pressure. That's for the factory tire size 265/70R16. I am now running 265/75R16. My current tires have more volume I would think that they would handle the same load with less air.
IvI' been running 29 lbs in them but I have considered increasing pressure a little.

Unfortunately I can't try your chalk trick as there's snow on the ground. I will rotate my tires and increase pressure some. I hope you are right.

 

Worn out edges would indicate under inflation but this is cupping on 1 edge only (per OP).

I'm not saying that it's not air pressure, that might be a factor but it's the alignment that is causing the 1 sided wear.

 

To help alleviate the problem of the inside edge wearing I increased tire pressure months ago to 38 psi in front. Did not seem to help.