Fill my tires to 65 psi?

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According to what it says on the sidewall of my cooper tires I can have a max load of 3000 lbs at 65psi. Is that how much I should put in for on road use?
 

klinetime574

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Need some more info to help you out.

What size are the tires? What width are the rims? How much weight are you carrying?

The best way is the chalk test. Chalk the treads of the tire. Drive straight on level ground for a little bit. Check your chalk marks. If the chalk is gone on the edges tire pressure is too low. If the chalk is gone in the center tire pressure is too high. (Disclaimer: never done it myself :hillbilly: ) But it sounds like that would work well.

If you fill them up that much you will have a harsh ride. I've never heard of anyone running over 50psi in an FJ6X
 
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Tires are 33 X 9.5 X 16 and I'm in an 87 FJ60. It is usually only lightly loaded and sometimes heavily loaded for bush trips. I would sacrifice some ride comfort for MPGs. I drive about 300 miles a week.
 
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Orangevale, CA
Yes you can put 65PSI in them, but I wouldn't unless you have 3000lbs of wiegt on each of them. If you run them w/65 psi w/o 3k lbs on each of them, it will ride like a rock. And you won't be putting all the tread to the pavement. My rig weighs in at almost 5k lbs and I have found 35 psi to be a good pressure.
 
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Tacoma, Washington
Which cooper tires? I run 36x9" on 16s and I run 22-24psi unloaded 25-26psi when fully loaded down.
Are they power kings or sta's or something? I would start at 32 and go down from there.
 

TS888

Almost the person my dog thinks I am...
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Those must be load range E tires. I'd run them at about 40 psi for pavement.

I envy your 16" wheels for the ability to get E range tires. I'm tired of patching my flimsy 15" range C BFG's every time I run over a piece of broken hard candy or a particularly rugged bug.
 
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victoria, bc
Actually they are load range D with 5 ply tread (1 nylon, 2 steel, 2 poly) and 2 ply poly sidewalls.... Cooper discoverer S/T and they are actually a bit over 33 at 255/85, 16 . I know about your BFG woes.... And cruisers seem to have them so often. I bought a few cruisers over the years with all-terrains and it was just blow out city. To put it simply, I hate those tires. Anyway, gonna try 40 psi and see how she goes. Thanks guys...
 
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Salem Oregon
just for your info 4ply =P 6ply=C 8ply=D 10ply=E

40psi unloaded is a great place to start, keep track of miles per gallon, also try the chalk test and you can find the rigs perfect tire pressure based on the results. good luck
 

TS888

Almost the person my dog thinks I am...
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just for your info 4ply =P 6ply=C 8ply=D 10ply=E

That used to be true, but now weight rating is assigned based on test results, so ply counts can vary. With aramid and other wovens, there are a number of ways to vary strength based on the warp and weft count and how the plys are offset, so E range tires can be 5 ply.

Yes, I'm a textile nerd. 20 years in the industry.
 

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