Cooper ST's - 255/85/16
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SOAZ
Tim and Kelsey get lost..
I have over 10,000 miles on my 255 cooper st's now. They're holding up very well. Almost no chunking. I was able to put a couple of chunks in there, but way less than my bfg muds. I've never got another flat.
The tires are so smooth I run about 40 psi on the street which is great for mileage.
I do about 20-25 offroad which works well and I always know I could go lower if needed.
I'll try and post some pics of the tires and how they've worn after the Four Peaks Pickup. Or feel free to eye ball them if your there. Very happy overall!
These things are grippy!
The tires are so smooth I run about 40 psi on the street which is great for mileage.
I do about 20-25 offroad which works well and I always know I could go lower if needed.
I'll try and post some pics of the tires and how they've worn after the Four Peaks Pickup. Or feel free to eye ball them if your there. Very happy overall!
These things are grippy!
Redline
Likes to Drive and Ride
Some think the snow/ice traction is terrific, others not as good as BFG ATs. I can see both viewpoints depending on the terrain, vehicle, driver, etc. Everything makes a difference.
Taking the tread compound out of the equation (which is softer/better I don't know) I can see the ice traction being a little less with the ST compared to the BFG AT as the STs don't have as much siping, and not as much siping at many different angles. I resisted siping mine before mounting to give them a chance, and to reduce the chance of chunking. I might still sipe them later.
I also would not be surprised about a slight loss in lateral grip due to the very narrow tread width compared to other 255s and particularly your past BFG 265s.
Taking the tread compound out of the equation (which is softer/better I don't know) I can see the ice traction being a little less with the ST compared to the BFG AT as the STs don't have as much siping, and not as much siping at many different angles. I resisted siping mine before mounting to give them a chance, and to reduce the chance of chunking. I might still sipe them later.
I also would not be surprised about a slight loss in lateral grip due to the very narrow tread width compared to other 255s and particularly your past BFG 265s.
dnellans said:
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Desertdude
Expedition Leader
James, what is your rotation/balancing ritual ?
Redline
Likes to Drive and Ride
The problem with me wearing tires is that recently I have been changing treads too often. The BFG MTs are pretty much dedicated to the Chaser and as spares, unless they go to my F350. My Bighorns have a few thousand on them and I like the way they performed off-highway this past year. They will likely see more hard off-road miles in 2008 as my preferred traction tire and some highway miles to get to events.
Either the Cooper STs or the Maxxis Bravo AT will receive the bulk of my 4Runner highway miles over the next year, I just have to decide which I prefer. The STs have the advantage of being a better off-highway tire than the Maxxis Bravos, with much more void, precisely the reason I bought them.
Either the Cooper STs or the Maxxis Bravo AT will receive the bulk of my 4Runner highway miles over the next year, I just have to decide which I prefer. The STs have the advantage of being a better off-highway tire than the Maxxis Bravos, with much more void, precisely the reason I bought them.
Jacket said:
Redline
Likes to Drive and Ride
Rotation:
In the past I have enjoyed good success with rotating every 3,000-5,000-mi. depending on the tires, use, etc. I have rotated as short as 2,500-miles but generally think this is too much work and unnecessary. I like 3,333-miles because it is three rotations every 10k instead of 3-plus rotations (maybe silly but I don't like to count 3,6,9,12,15,18,21...)
On my old diesel truck which has gone through a few sets of tires, I have always used and still prefer to rotate: fronts crossed to the rear, rears straight forward to the front axle (on same side of truck)- a rearward cross.
Balancing:
I'm a regular customer of Les Schwab and have one local store that does all my mounting and balancing. I buy most, but not all my tires from this store. In the past I would take my trucks in for a rotation and they would rotate my tires as I specified above (I think simple X-pattern or front-to-back is more common), and rebalance the tires going to the front. Often all four would be rebalanced if I asked or the manager told them to. There is no charge for rebalancing tires purchased from Les Schwab. I have been using aluminum wheels almost exclusively for the past several years, Ford, Jeep, Toyota, with only one set of aftermarket Ultras for the Toyota briefly which were recently sold.
Lately I have been doing my own rotations in my shop and just getting my tires rebalanced as needed. The FJC TRD wheels I'm using don't have an outer lip for wheel weights. Weights can be hammered onto the inner rim and tape weights put on the inside of the wheel in a groove made for tape-weights, allowing a two point 'dynamic' balancing method. But I have been having the TRD wheels balanced with the 'static' (that's what they call it, though the tires are still spin balanced) one point method. This is technically not the preferred method for a superior balance. But this does keep the weight up and out of the way where it is much less likely to be moved by rocks, and the machine will also require less weight when this static method is used.
As I'm sure you know, the Toyota stud-centric wheels can be difficult to balance as the balance machines at tire shops usually use the center/hub opening to mount the wheel to the machine. Though they can use an adapter to try to center the wheel with the stud holes, it appears that if they tried to use that adapter at my local store on my TRD wheels the adapter might touch the face of the wheel and scratch it. With aluminum TRD wheels and attention to detail they have been doing a good job using the single point, static method. The stock wheels on my ‘05 Rubicon were worse, as the little hub cap opening on the front of the wheel wouldn't allow for centering of the wheel on the machine. They would use a rubber padded cone on the face of the wheel and a small steel cone on the back side of the wheel.
Though my Maxxis Bighorn MT and Bravo AT both called for very little wight when balancing, I think that the lighter Cooper STs balanced better and run even smoother down the highway. I did have my Bighorns rebalanced last week but have yet to put them on the 4Runner. The last time they were on the Mall Crawler they felt like they could use a ‘tune up'.
On my F350 I have been using Centramatic continuous wheel balancers for about a year. They are good and are currently balancing some large aggressive mudders that don't have any other wheel weight on the wheel.
http://www.centramatic.com/
Centramatics won't fit on the front of my 4Runner because of caliper clearance (the lack of clearance) so I must use regular wheels weights.
In the past I have enjoyed good success with rotating every 3,000-5,000-mi. depending on the tires, use, etc. I have rotated as short as 2,500-miles but generally think this is too much work and unnecessary. I like 3,333-miles because it is three rotations every 10k instead of 3-plus rotations (maybe silly but I don't like to count 3,6,9,12,15,18,21...)
On my old diesel truck which has gone through a few sets of tires, I have always used and still prefer to rotate: fronts crossed to the rear, rears straight forward to the front axle (on same side of truck)- a rearward cross.
Balancing:
I'm a regular customer of Les Schwab and have one local store that does all my mounting and balancing. I buy most, but not all my tires from this store. In the past I would take my trucks in for a rotation and they would rotate my tires as I specified above (I think simple X-pattern or front-to-back is more common), and rebalance the tires going to the front. Often all four would be rebalanced if I asked or the manager told them to. There is no charge for rebalancing tires purchased from Les Schwab. I have been using aluminum wheels almost exclusively for the past several years, Ford, Jeep, Toyota, with only one set of aftermarket Ultras for the Toyota briefly which were recently sold.
Lately I have been doing my own rotations in my shop and just getting my tires rebalanced as needed. The FJC TRD wheels I'm using don't have an outer lip for wheel weights. Weights can be hammered onto the inner rim and tape weights put on the inside of the wheel in a groove made for tape-weights, allowing a two point 'dynamic' balancing method. But I have been having the TRD wheels balanced with the 'static' (that's what they call it, though the tires are still spin balanced) one point method. This is technically not the preferred method for a superior balance. But this does keep the weight up and out of the way where it is much less likely to be moved by rocks, and the machine will also require less weight when this static method is used.
As I'm sure you know, the Toyota stud-centric wheels can be difficult to balance as the balance machines at tire shops usually use the center/hub opening to mount the wheel to the machine. Though they can use an adapter to try to center the wheel with the stud holes, it appears that if they tried to use that adapter at my local store on my TRD wheels the adapter might touch the face of the wheel and scratch it. With aluminum TRD wheels and attention to detail they have been doing a good job using the single point, static method. The stock wheels on my ‘05 Rubicon were worse, as the little hub cap opening on the front of the wheel wouldn't allow for centering of the wheel on the machine. They would use a rubber padded cone on the face of the wheel and a small steel cone on the back side of the wheel.
Though my Maxxis Bighorn MT and Bravo AT both called for very little wight when balancing, I think that the lighter Cooper STs balanced better and run even smoother down the highway. I did have my Bighorns rebalanced last week but have yet to put them on the 4Runner. The last time they were on the Mall Crawler they felt like they could use a ‘tune up'.
On my F350 I have been using Centramatic continuous wheel balancers for about a year. They are good and are currently balancing some large aggressive mudders that don't have any other wheel weight on the wheel.
http://www.centramatic.com/
Centramatics won't fit on the front of my 4Runner because of caliper clearance (the lack of clearance) so I must use regular wheels weights.
Desertdude said:
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Redline
Likes to Drive and Ride
Desert Dude:
I thought of something that is related to your rotation/balance question; tire pressures.
I don't run lots of air-pressure, even on my F350. It has never seemed to cost me MPG or tire wear, and I believe it assist with traction, handling and ride quality. I don't run low/under-inflated tires, merely appropriate PSI for the load. Light loads means less PSI, more weight requires more PSI. On my lighter vehicles (Jeep/Toyota) it is easy to pick one on-highway PSI that works on the car and stick with it unless you like to play with things like I do.
My practice.
An LT255/85R16D and LT265/75R16D both are rated to carry 3,000-lbs per tire in a SRW (single rear wheel) application at 65-PSI. Since few of us are driving 4x4s weighing 12,000-lbs (6k on each axle) this is too much pressure. The tires will be overly firm, hurting both ride quality and traction.
At 35-PSI the 255/85 is rated for 1920-lbs and the 265/75 is good for 1910-lbs. That is close enough to not matter and I will use the 255/85 capacity as that is the size I prefer. At 35-PSI there is still much more capacity than is usually needed, 3,840-lbs! I don't think it is bad to simply run 35-psi, but I don't think people need to go above that for better MPG. The tires are already pretty pumped-up unless the truck has 3,840-lbs on each axle.
The inflation charts I have seen don't go below 35-psi and maybe that is because there are no standards for less psi, but I don't accept the notion that the tires are not safe to be run at lower than 35-psi if the load is light for a given tire. An example of this is on my ‘06 4Runner. According to Toyota and the sticker on the door jam the stock P265/70R16 tires were rated to carry 3,295-lbs at 32-psi on the rear axle. The front axle is only rated for 2710-lbs and Toyota suggests the same 32-PSI (KISS I believe). These are the gross axle weight ratings (GAWR) for the vehicle. If the axles are carrying less weight, and they are even after all my modifications, they don't really even need the full 32-psi. Remember this is after the Ford Explorer/Firestone mess and I'm confident there is extra capacity built into this 32-psi number for Toyota's legal department. Why 32 instead of 35, because 35 is overkill and overall ride, handling, and traction will be better with the appropriate, lower psi.
This doesn't mean that I run 25-psi on the highway, but I have experimented with pressures below 30-psi. My current air pressure for my 4Runner is 32, just because that's what Toyota recommends, it rides and drives well and the TPMS sensors don't put a light on the dash. I have experimented with less, and just yesterday drove a short distance with 35, which I promptly bled out upon returning home as it didn't feel right. I'm not finished experimenting ☺
I thought of something that is related to your rotation/balance question; tire pressures.
I don't run lots of air-pressure, even on my F350. It has never seemed to cost me MPG or tire wear, and I believe it assist with traction, handling and ride quality. I don't run low/under-inflated tires, merely appropriate PSI for the load. Light loads means less PSI, more weight requires more PSI. On my lighter vehicles (Jeep/Toyota) it is easy to pick one on-highway PSI that works on the car and stick with it unless you like to play with things like I do.
My practice.
An LT255/85R16D and LT265/75R16D both are rated to carry 3,000-lbs per tire in a SRW (single rear wheel) application at 65-PSI. Since few of us are driving 4x4s weighing 12,000-lbs (6k on each axle) this is too much pressure. The tires will be overly firm, hurting both ride quality and traction.
At 35-PSI the 255/85 is rated for 1920-lbs and the 265/75 is good for 1910-lbs. That is close enough to not matter and I will use the 255/85 capacity as that is the size I prefer. At 35-PSI there is still much more capacity than is usually needed, 3,840-lbs! I don't think it is bad to simply run 35-psi, but I don't think people need to go above that for better MPG. The tires are already pretty pumped-up unless the truck has 3,840-lbs on each axle.
The inflation charts I have seen don't go below 35-psi and maybe that is because there are no standards for less psi, but I don't accept the notion that the tires are not safe to be run at lower than 35-psi if the load is light for a given tire. An example of this is on my ‘06 4Runner. According to Toyota and the sticker on the door jam the stock P265/70R16 tires were rated to carry 3,295-lbs at 32-psi on the rear axle. The front axle is only rated for 2710-lbs and Toyota suggests the same 32-PSI (KISS I believe). These are the gross axle weight ratings (GAWR) for the vehicle. If the axles are carrying less weight, and they are even after all my modifications, they don't really even need the full 32-psi. Remember this is after the Ford Explorer/Firestone mess and I'm confident there is extra capacity built into this 32-psi number for Toyota's legal department. Why 32 instead of 35, because 35 is overkill and overall ride, handling, and traction will be better with the appropriate, lower psi.
This doesn't mean that I run 25-psi on the highway, but I have experimented with pressures below 30-psi. My current air pressure for my 4Runner is 32, just because that's what Toyota recommends, it rides and drives well and the TPMS sensors don't put a light on the dash. I have experimented with less, and just yesterday drove a short distance with 35, which I promptly bled out upon returning home as it didn't feel right. I'm not finished experimenting ☺
Desertdude said:
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jim65wagon
Well-known member
I've run everywhere from 34-44 in the front and 30-40 in the rear; excepting the two loads of dirt when I put 55 in the rears. I never really noticed any difference in the gas mileage from the different air pressures. I like the way the front feels at 36 and the rear at 34.
At 27,000 miles I think I've got more miles on them than most of you; I'm still looking for 45,000 out of them...
Redline has the most informative tire thread I've ever read!
James; just to satisfy my never ending curiosity of tire figures; how much difference in height is there between all these 255s? Is any one of them significantly taller or shorter than the others?
At 27,000 miles I think I've got more miles on them than most of you; I'm still looking for 45,000 out of them...
Redline has the most informative tire thread I've ever read!
James; just to satisfy my never ending curiosity of tire figures; how much difference in height is there between all these 255s? Is any one of them significantly taller or shorter than the others?
jim65wagon said:
There isn't enough difference to be a difference. Actual height depends on the application, tire pressures and load, and as between two tires, the sidewall construction. Too many variables to be making choices based on one tenth inch difference in static heights posted in spec charts.
Streakerfreak
Jan-Kee
This was a great and helpful thread! Thanks for all the info you guys posted up, it helped me make my final descion... on Friday I will be the new owner of some Cooper ST's 255/85/16:26_7_2: