Pssssst....Cooper STT Pro Owners........Come Here......

FWIW, I have Cooper AT3s currently, and I had DT try to balance them multiple times without success. So I bit the bullet and took it to toyota; smooth as butter. I was getting serious steering wheel shakes around 50-70 mph. Ive now gone up to 80+ and its all smooth. When I asked he tech at toyota if he had to adjust the weight on the tires/wheels he said 'yes, very much, had to add dynamic weights'

All in all, I would give Toyota a try to balance, align correctly before swapping tires.

 

I don't have the typical unbalanced tire vibration/wobble. Mine only happens after sitting for 24+ hours then goes away after 4-5 miles, like old bias-ply tires.

 

my cooper at3's are hands down the best tire I've ever purchased.. Potential cooper customer for life.

 

What's your tire pressure OP? Also it's a mud terrain. Anybody who buys mud terrains is buying them because they REALLY NEED them and therefore have no choice but to put up with the sound

 

Are you by chance running lug centric wheels? I similar issue since switching to aftermarket wheel that is lug centric.

 

Factory wheels.

 

I tested multiple pressures doing the chalk test so they're exactly where they need to be.
I've owned 4wd vehicles for 25+ years, most of them having mud terrains, from Dodge dually's to Jeeps, & never had any this loud or this rough.

 

I don’t have them, but I have Cooper Discoverer A/T3 and they get the flat spot you’re describing.

Parked at work from 7am to 4pm. Leave the parking lot and get straight on the freeway. It usually shakes for the first half mile or so. I don’t notice it in the morning, but I have a mile or so of slow driving before getting on the freeway. So they’re probably warmed up enough by then.