37 Cooper STT Pros on ATX Slabs balance issues

[Daniel Partida]

Ok so kinda starting to pull some hair out, so bought some 37x13.50R17 Cooper Stt Pros and mounted on some ATX Slab beadlocks, tried to balance them with stick on weights at work with a Hunter tire balance machine, first one took about 40oz of weight and finally balanced, second one asked for 32oz on the first run, 12oz on a second pass and wanted to add even more on the third try so I stopped. That's way more weight that I've ever put on 37s, I think my last set of procomps took about 15 or 16oz on the worst one. Tried adding one of the wheels I still haven't mounted a tire to and added the ring and bolts and perty much balanced according to the machine, if throwing the beadlock on the machine to check its balance is a thing. So bad tires? Or maybe I'm installing them wrong? Always go in a back and fourth pattern to torque the rings down to 25ft-lbs according to ATX wheels bolt torque. And I'm doing probably 10 or more passes increasing in torque. Was also thinking on throwing one of the tires on a non beadlock wheel and seeing if it balanced or took alot less weight to balance then might be the beadlocks? Or my installation????...please help! don't have much hair left lol

 

[Cousin Clyde]

Holy shit look at all those weights.

 

[jeeeep]

Your install procedure sounds correct.

I'd take them off the wheels and check the wheels alone, start with the one that took the most weights.

ATX Slabs were offered in machined and black, is that a powder coat or spray paint?

I think my STT Pros took a lot of weights as well but nothing like what you've got, I'll check tomorrow and post what I find.

 

[Daniel Partida]

Yeah was gonna do that, remove the one that took alot of weight and try running that one on the balancer see if it looks or shows that it needs weight or is not circular. Cuz I'm really running out of ideas. But willing to keep pushing to resolve this dilemma.

But wheels were black with polished ring and just painted them with automotive paint and added metallic bronze powder to the clearcoat before praying it. Looks alittle darker than standard cooper and in the sun they shine. Couldn't be happier on how they turned out. And switched out the bolts to black ones.

 

[Bear_JT]

Try driving it without balancing and see how it feels. I don’t have my KMC’s with Nitto’s balanced at all and it rides great.

 

[Daniel Partida]

Yeah I've heard those nittos are usually perty darn round and don't need weights. But just trying to avoid any chance of getting deathwobble or adding to that possibility of getting it as I've suffered a few times and replaced basically all the suspension and now I'm on the new tires as I've been told you should probably change tires after getting deathwobble a few times with them and needed them soon so why not refresh it all

 

[Mike Pierson]

I just switched from STT Pros to Nittos. My Pros needed a bunch of weight to balance as well, not quite that much though. Make sure you dynamic balance those, once that was done the balanced fairly well, but not perfect.

The Nittos on my KMC’s were nearly balanced right after install. I only took them in to Discount for balancing bc there was a little shimmy over 70mph.

 

[OverlanderJK]

Cooper makes square tires because they are owned by Goodyear and gay.

 

[Cousin Clyde]

@Daniel Partida , that’s pretty cool you have the ability to do this yourself.

My 37” Coopers balanced ok per the shop that did the work…maybe you just got a difficult batch…Good luck getting it figured out.

 

[CalSgt]

The shop that balanced my coopers wanted me to drive on them for a week before they spun them.
Guy claimed they settle and move a bit and balance better that way.

 

[Ddays]

I've had Cooper STT Pros in 37 & 40". The 37's were great. The set of 40's I swear they sent me a square one. It was fucking awful. The Cooper rep actually was in the shop the following day when I took it back & he had it replaced. With that one out of the way they were great & all 4 took little weight to balance.

You may have just got a bad tire

 

[Mike Pierson]

The shop that balanced my coopers wanted me to drive on them for a week before they spun them.
Guy claimed they settle and move a bit and balance better that way.

That kinda fits with my situation, had to take them back a few times within a week to get it right.

 

[JT@623]

The shop that balanced my coopers wanted me to drive on them for a week before they spun them.
Guy claimed they settle and move a bit and balance better that way.

That and gives them a week to wear off the bad spots

 

[Daniel Partida]

Maybe that might be a case to try and run them abit and then try to do the balancing, they do have a 45 day return policy. Gonna redo my rings maybe didn't do the right bolt torque procedure or something and see if anything changes. One of the tires visually was alittle wobbly so maybe pinched alittle more on one side.

 

[Daniel Partida]

Well took one of the wheels that I added to the balancer and balanced perfectly and spun true, followed the correct torque pattern for 24bolts and gonna try balancing this one later on today and see what it shows....

 

[Mike Pierson]

Well took one of the wheels that I added to the balancer and balanced perfectly and spun true, followed the correct torque pattern for 24bolts and gonna try balancing this one later on today and see what it shows....

When you go to add the ring, you’ll see a number of rings between an inch or two from the bead. Use those to help center the ring on the tire.

 

[Daniel Partida]

When you go to add the ring, you’ll see a number of rings between an inch or two from the bead. Use those to help center the ring on the tire.

Yup was trying to use those as a guide and does look like its perty darn centered after doing the torque pattern for the 24 bolts, looks like pushed on the same amount of tire. Great idea though

 

[jeeeep]

Yup was trying to use those as a guide and does look like its perty darn centered after doing the torque pattern for the 24 bolts, looks like pushed on the same amount of tire. Great idea though

because the bead on the coopers is thicker, I did use a Hz laser level to check that the bead ring was even all around.

Also checked my JKU with the Coopers, they have more weight than the BFG's and Nitto but nothing like what you are dealing with.

 

[bmkrinne]

My 37x12.50 STT pros on KMC beadlocks all have anywhere from 2 to 4 oz of weight. None have the amount of weight you have especially being 180 deg out. All weights are in one location.

 

[Daniel Partida]

My 37x12.50 STT pros on KMC beadlocks all have anywhere from 2 to 4 oz of weight. None have the amount of weight you have especially being 180 deg out. All weights are in one location.

Yeah I'm really thinking I got 2 bad tires so far, did balance one still in the 12oz but did balance good. The bad tire I couldn't balance mounted it on a non beadlock wheel and right away could see it wobbly and taking 20oz right away so might be switching 2 out