Cooper STT Pro pressure

CybrSlydr

CybrSlydr

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So, I think I've made the decision to go with the Cooper STT Pros, though I won't be getting them for a couple months at best (was invited to a wedding and money I was going to spend getting new tires is going into a suit, hotel and all that jazz...).

If you've run these tires before, what PSI were you running? I mostly ask as the guy in this vid had to air down quite a bit to get full tread contact with the road.


Or is he incorrect about trying to get full tread contact with the road? Seems to me if you want it to wear evenly, you'd want the whole tread to meet the road surface.
 
bobthetj03 said:
I had the 1st gen STT's and ran them at 26 psi. Had pretty even wear at that pressure.
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Ok - guy in that vid says he went down to around 26-28psi for his Cherokee. Good to see that appears to be the proper psi for the Wrangler as well!
 
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For a TJ the general rule is 24-26 psi for that size LT tire on that size rim regardless of whether it is C, D or E load rated. Experiment from there. A heavier rig might might require a bit more air pressure. For my LJ with "metric 35's" [315/75] the optimum street pressure seems to be 26-28 psi.
 
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Piggybacking on this thread. Is ~28psi the right pressure for 265/75R16s as well?
 
I've run them at 22, 24, 25 and 26. I liked the ride quality at 24 but currently run them at 25-26. When I get off-road I air them down to 11-12.
 
JMT said:
I've run them at 22, 24, 25 and 26. I liked the ride quality at 24 but currently run them at 25-26. When I get off-road I air them down to 11-12.
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Wow, that's really low - does the tire have a listed suggested air-down psi?
 
CybrSlydr said:
Wow, that's really low - does the tire have a listed suggested air-down psi?
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No listed air down psi that I’ve found. I just followed suggestions of forum members. I think for a load C tire 10-12psi is a good recommendation across the board. The tire patch doesn’t really spread out much until you drop below 15psi. With Load D or E tires, recommended air down pressures could be slightly different for optimal performance off-road.
 
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this is good information. im picking mine up on monday. think il just start out at 24.
One other question what kind of milage do you get out of the cooper. in the real world
 
Boinked said:
this is good information. im picking mine up on monday. think il just start out at 24.
One other question what kind of milage do you get out of the cooper. in the real world
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The vids I've watched on YouTube say you should, with regular rotation, get around 50k out of them.

 
I have no experience with the Cooper Discoverer STT Pro, but I do have experience with the Cooper Discoverer ST/Maxx which is marketed as a commercial traction tire but can also be described as an aggressive AT tire. They are mounted on my "non-jeep" overlanding vehicle.

I have been rotating my ST/Maxx's every 4,000 miles and recording the tread depth each time. I anticipate getting about 40,000 miles from them, which is excellent for any tire that is used off pavement to any significant degree. (I consider tires worn out when the tread is down to 4/32" rather than the legal limit in most states of 2/32" which I think of as "bald." Braking and wet weather performance deteriorates rapidly with tread depth less than 4/32".).

BTW, Cooper offers a 50,000 mileage warranty for their AT3 all terrain tires, but not for their tires with more aggressive treads such as the ST/Maxx or STT Pro.
 
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CybrSlydr said:
The vids I've watched on YouTube say you should, with regular rotation, get around 50k out of them.

Click to expand...
My tire guy has a set of Cooper STT Pro's in 35x12.5 and he had 50,000 on them. He was surprised. I saw them. They were on their last leg, but 50K, that's a lot of miles. Mine currently have about 6,000. I rotate every 4-5000 miles. I need to check the tread depth.
 
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Ive been happy with my Pro's so far, probably about 3-4k miles on them, they're not very loud on the road (although I have a lot of wind noise so don't really hear the tires), they look the part and have performed well on and off road for the light use I have put them through. Normally run at 25 PSI, air down to about 15.
 
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I wore my 1st gen STT's down to 4/32's and got 23K miles out of them, 80% DD duty, so I hope they improved the 2nd gen STT pro.
 
I did the chalk test and found out that, 22 psi hot, was good for my 37's. And 8-10 psi hot when aired down. It's not a daily driver though.
 
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