Redline
Likes to Drive and Ride
Yeah, aftermarket UCA allow for that kind of caster adjustment.
Cooper Discoverer S/T Maxx
- Thread starter jim65wagon
- Start date
Yeah, aftermarket UCA allow for that kind of caster adjustment.
java
Expedition Leader
Yeah, just not in the budget right now.... Especially when I need tires! Arrg.
How bad was it on your 4r?
1stDeuce
Explorer
Talked to cooper Engineer at SEMA
I had a conversation with Cooper at SEMA this year about several things concerning STMaxx and other tires using the 3-ply carcass...
Right pull was one of the things that we talked about specifically. I just put a new set of 255/85R16 STMaxx's on my TJ, and I was happy to note that they do not seem to pull at all. (I drove it to SEMA and back, ~1000mi, so I'm confident that there is no pull at this point.) He could come up with no reason that the tires would pull on some vehicles, and not on others. (Expo reports of pulling thus far on Redline's IFS toyota, your 80 series, and on KojackJKU's JK unlimited, in various sizes I believe.)
Theories that we could come up with involved slight cone shape, ply orientation, alignment settings, tread design, etc. Nothing makes any sense once you take tire position swapping into effect, and yet a few people have commented that they do seem to induce a right pull. (Always a right pull, never left...)
I have my tires all mounted with the DOT codes facing outward. (255/85R16's are blackwall tires) That should be the same as mounting them with white letters all in or all out. On a truck that is pulling, it might be interesting to mount both front tires with white letters right to see if that does anything for for the right pull. That's about the only thing that hasn't been tried, but Cooper says there's no difference to anything from a construction perspective that would lend to right or left pull.
And even stranger, some vehicles don't pull at all, and others pull very noticeably, and as Redline found, require really high cross caster to correct the pull...
In the case of the 80 series, there IS potential to change caster. You need offset kingpin bearings. Specialty Products is finally making them for the 80 series in 3 degree (for lifted vehicles) and 1 degree (for trucks with too much negative camber, which is most...)
My Jeep is running slightly positive (~.2-.4 degrees) camber, and about 5 degrees of caster. Redline's IFS toyota would have ideally had zero or slightly positive camber also, but much lower caster initially. (spec is ~2.5 deg caster both sides) Not sure about KojackJKU's JK. Ideally it should have been near zero or slightly negative camber, and ~4.5 degrees of caster. He got different tires to fix the pull.
If you do rotate just one tire on the rim, let us know if it works. And what size tires are you running anyway??
Chris
I had a conversation with Cooper at SEMA this year about several things concerning STMaxx and other tires using the 3-ply carcass...
Right pull was one of the things that we talked about specifically. I just put a new set of 255/85R16 STMaxx's on my TJ, and I was happy to note that they do not seem to pull at all. (I drove it to SEMA and back, ~1000mi, so I'm confident that there is no pull at this point.) He could come up with no reason that the tires would pull on some vehicles, and not on others. (Expo reports of pulling thus far on Redline's IFS toyota, your 80 series, and on KojackJKU's JK unlimited, in various sizes I believe.)
Theories that we could come up with involved slight cone shape, ply orientation, alignment settings, tread design, etc. Nothing makes any sense once you take tire position swapping into effect, and yet a few people have commented that they do seem to induce a right pull. (Always a right pull, never left...)
I have my tires all mounted with the DOT codes facing outward. (255/85R16's are blackwall tires) That should be the same as mounting them with white letters all in or all out. On a truck that is pulling, it might be interesting to mount both front tires with white letters right to see if that does anything for for the right pull. That's about the only thing that hasn't been tried, but Cooper says there's no difference to anything from a construction perspective that would lend to right or left pull.
And even stranger, some vehicles don't pull at all, and others pull very noticeably, and as Redline found, require really high cross caster to correct the pull...
In the case of the 80 series, there IS potential to change caster. You need offset kingpin bearings. Specialty Products is finally making them for the 80 series in 3 degree (for lifted vehicles) and 1 degree (for trucks with too much negative camber, which is most...)
My Jeep is running slightly positive (~.2-.4 degrees) camber, and about 5 degrees of caster. Redline's IFS toyota would have ideally had zero or slightly positive camber also, but much lower caster initially. (spec is ~2.5 deg caster both sides) Not sure about KojackJKU's JK. Ideally it should have been near zero or slightly negative camber, and ~4.5 degrees of caster. He got different tires to fix the pull.
If you do rotate just one tire on the rim, let us know if it works. And what size tires are you running anyway??
Chris
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Hilldweller
SE Expedition Society
I've got the 255/80-17 on my JKU and have no pulling issues at all. Over 19K miles on them.
Redline
Likes to Drive and Ride
I don't know how the share that... I'm very particular and require that my vehicles drive perfectly straight. My notes are not handy buy my memory is that it would change lanes in 5-7 seconds with 'hands off' the wheel.
java
Expedition Leader
Ok thanks, Im used to driving a twitchy truck already at this point, although I will get UCA's at some point, I just don't want it to be worse than it is.
Redline
Likes to Drive and Ride
And my IFS Tundra too, but that was two years ago and for a very short time. I likely could have adjusted the SPC/Light Racing UCA to increase the cross-caster on the Tundra as I did on the 4Runner earlier this year. At the time I didn't want to do that, as I also had a set of ******** Cepek FC-II that I wanted to continue using; they liked about 0.90* cross-caster.
Redline
Likes to Drive and Ride
On my car with 'enough' caster (diff. UCA) they were never twitchy, just a right pull, just like I've experienced with Toyo M/T and M55.
Don't Buy Cooper ST Maxx Tires
I have 16K miles on a set of 255/80-17 on stock rims on my 2014 JKU Sport with an AEV 2.5 Lift that has pulled right from day one. Tires have been rotated every 3-5K miles (5 tire rotation). Lift professionally installed by authorized AEV Dealer. Lift specs and installation checked and re checked by 2 reputable shops. The jeep has been on more alignment racks than I can count. The jeep will get new ball joints next week to see if that helps. DON"T BUY ST MAXX TIRES!!!!!! I think I have a tire problem!. Looking for volunteers in NJ to try my tires and wheels. Thanks
I have 16K miles on a set of 255/80-17 on stock rims on my 2014 JKU Sport with an AEV 2.5 Lift that has pulled right from day one. Tires have been rotated every 3-5K miles (5 tire rotation). Lift professionally installed by authorized AEV Dealer. Lift specs and installation checked and re checked by 2 reputable shops. The jeep has been on more alignment racks than I can count. The jeep will get new ball joints next week to see if that helps. DON"T BUY ST MAXX TIRES!!!!!! I think I have a tire problem!. Looking for volunteers in NJ to try my tires and wheels. Thanks
1stDeuce
Explorer
SandCuda, can you give me a scan of your latest alignment settings just for fun? I was starting to think it was a 285 problem, but now here you are with 255's, and a guy above with 15k miles and no pulling on the same size... Doesn't make sense.
Just to be clear, this isn't steering wheel off center, but rather if you straddle the yellow line, the car heads right, and fairly quickly, right? There has to be a reason. If it is a problem with the tires, swapping them side to side should reverse the pull...
And a good alignment shop CAN fix it with the alignment using the balljoints... Or perhaps camber shims, depending on what your alignment looks like. (Shims are a LOT cheaper if you don't need balljoints.)
Just to be clear, this isn't steering wheel off center, but rather if you straddle the yellow line, the car heads right, and fairly quickly, right? There has to be a reason. If it is a problem with the tires, swapping them side to side should reverse the pull...
And a good alignment shop CAN fix it with the alignment using the balljoints... Or perhaps camber shims, depending on what your alignment looks like. (Shims are a LOT cheaper if you don't need balljoints.)
Redline
Likes to Drive and Ride
Exactly what I did with my new live-axle Ram/Cummins project.
The truck pulled right with the stock tires, and with the first set of aftermarket tires (stock size) I put on factory wheels... An offset ball joint from SPC corrected the problem. This is more than most are willing to do/spend, but worth a few hundred dollars to me. I like my trucks to drive straight. :smiley_drive:
1stDeuce, after tire rotations or just swapping fronts it still pulls right. On a fairly flat road, doing 40 mph, if I let go of the steering wheel the jeep will be in the shoulder in 75-100 feet. The jeep will drive nice, no hands no wonder, if I'm traveling on a left crowned road surface. The steering wheel center has been maintained closely during each alignment with the AEV ProCal and checked just yesterday. I will dig out my last alignment print out from the glove box and post tomorrow. I hope its not the AEV Lift. I wish I kept my stock tires. I could swap and compare.
I thought it was my lift, ball joints, control arms etc etc. Never thought of the tires, until I swapped them for the BFG and realized it was the tires. went back to the dealer and they said yes, a lot of people are complaining regarding the right pull of the maxx.