37 Cooper STT Pros on ATX Slabs balance issues

[cozdude]

I’m sure the tire has a shifted belt. My set of coopers were bad. They never balanced good and would always be out of balance by the next oil change. It’s one of the things I hated about them.

 

[dchew]

I have a love hate relationship with my STT Pro’s. They hook up great but they are a pain to balance, and they wear in a way that is noisy and perpetually need rebalancing

 

[Daniel Partida]

So small update, decided to order 1 Mikey Thompson Baja Boss M/T and see if I had better luck with mounting those tires and hope has been restored, these balanced with only 7oz of total weight instead of the 30+ ounces for the Coopers. Decided to order 4 more and going to go ahead and hopefully all balance fairly easily.

 

[Daniel Partida]

Happy to report that I was able to mount all 5 Baja Boss tires with the worst taking 16oz of weight, and the best was 7oz, so not bad at all. Sent back the Coopers. Also found my driver lower adjustable ball joint had play so torqued that one down and so far my suspension feels nice and solid. Only issue now is tracking a decent right pull. Pulls me out to the next lane in less than 3 seconds of letting go of the steering wheel. Does feel like its more than just the crown on the road...was maybe thinking could be bad thrust angle so threw it on the alignment rack at work and is actually not bad and actually looks like it would be helping me if anything with a right pull if I understand positive thrust angle correctly. Could it just be radial pull from the tires? Not super bad but do have to always keep pressure to the passenger side with the steering wheel to keep it going straight.

 

[OverlanderJK]

What’s your tire pressure? Looks high.

 

[Ddays]

Happy to report that I was able to mount all 5 Baja Boss tires with the worst taking 16oz of weight, and the best was 7oz, so not bad at all. Sent back the Coopers.

Ironically, Cooper makes those MT's

 

[Daniel Partida]

What’s your tire pressure? Looks high.

That's actually another thing I wanted to look into see what tire pressure I should run in these tires, I think they are load range D. Right now I'm currently running them at 27psi but might drop them see if anything changes.

 

[Daniel Partida]

Ironically, Cooper makes those MT's

Really liked the look of the 13.50 wide STT PROs but had so many issues trying to balance them so decided to try these as I've heard good things along with the Nittos. But only running some almost fully built Dana 44s cant go wrong with having less weight/mass on the smaller axles.

 

[2013rubirick]

I run 40” STT pros on atx slabs and have never balances them. They run smooth.

 

[2013rubirick]

I run 40” STT pros on atx slabs and have never balances them. They run smooth.

So I picked my jeep up after getting a 392 installed the other day and mine definitely are out of balance. I guess the jeep just never went fast enough to wobble as it only happened above 75. I did have them balanced yesterday and they are pretty smooth now. Not perfect but I think it’s from the distance of the lugs on the tires. To me it feels like you can feel them while driving. Maybe I’m crazy though.

 

[Mike Pierson]

So I picked my jeep up after getting a 392 installed the other day and mine definitely are out of balance. I guess the jeep just never went fast enough to wobble as it only happened above 75. I did have them balanced yesterday and they are pretty smooth now. Not perfect but I think it’s from the distance of the lugs on the tires. To me it feels like you can feel them while driving. Maybe I’m crazy though.

You can definitely feel them, especially when they’ve chunked.