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Tire pressure

Bluelinebuild

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Maybe you guys can help me out here. Just made the switch to yokohama geolander M/T tires. Max psi is 80 psi according to the sidewall and of course the door jam states 36 psi for factory tires. My question is what psi would be best 80 psi seems crazy high but with an 80 psi rating, 36 psi seems to low. Anyone know what psi I should be running at. I searched google and have gotten everything from 26 psi - 60 psi. I have no clue whats best to run at this point for on road psi. Any help is greatly appreciated!
 

z0n3

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I have E load ridge grapplers and run them at 50psi. I didn’t want to run them much higher to avoid a rougher ride or really low and wear the tires out incorrectly.
 

MG99

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Maybe you guys can help me out here. Just made the switch to yokohama geolander M/T tires. Max psi is 80 psi according to the sidewall and of course the door jam states 36 psi for factory tires. My question is what psi would be best 80 psi seems crazy high but with an 80 psi rating, 36 psi seems to low. Anyone know what psi I should be running at. I searched google and have gotten everything from 26 psi - 60 psi. I have no clue whats best to run at this point for on road psi. Any help is greatly appreciated!

When I went to Duratracs off a Rebel, which is also max 80 psi, I followed the factory recommendation of 55 front and 45 in the rear. Feels good to me.
 

Bluelinebuild

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Thanks for the info guys, im going to raise it to around 50 psi.
 

NJC1684

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Maybe you guys can help me out here. Just made the switch to yokohama geolander M/T tires. Max psi is 80 psi according to the sidewall and of course the door jam states 36 psi for factory tires. My question is what psi would be best 80 psi seems crazy high but with an 80 psi rating, 36 psi seems to low. Anyone know what psi I should be running at. I searched google and have gotten everything from 26 psi - 60 psi. I have no clue whats best to run at this point for on road psi. Any help is greatly appreciated!

 

bingo23

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If i used that calculator correctly it suggested I go to 35psi. Seems too low. I’ll stay at 55/45 for now.

What are the exact tire sizes your used with the calculator?
 

bingo23

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Maybe you guys can help me out here. Just made the switch to yokohama geolander M/T tires. Max psi is 80 psi according to the sidewall and of course the door jam states 36 psi for factory tires. My question is what psi would be best 80 psi seems crazy high but with an 80 psi rating, 36 psi seems to low. Anyone know what psi I should be running at. I searched google and have gotten everything from 26 psi - 60 psi. I have no clue whats best to run at this point for on road psi. Any help is greatly appreciated!

Blueline, are you going from a 275/55R20 (without the 'P') SL, to an LT275/65R20 load range E?
 

NJC1684

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If i used that calculator correctly it suggested I go to 35psi. Seems too low. I’ll stay at 55/45 for now.

I'm running 45 in my Ridge Grapplers. Went from the factory 275/55r20 to a LT275/60r20.
 

MValdez

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They should be inflated to the factory recommended psi on door pillar , 36psi. tire ratings are for MAX pressure at max load, not the recommended setting for all vehicles that are running that tire.
 

MG99

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Maybe you guys can help me out here. Just made the switch to yokohama geolander M/T tires. Max psi is 80 psi according to the sidewall and of course the door jam states 36 psi for factory tires. My question is what psi would be best 80 psi seems crazy high but with an 80 psi rating, 36 psi seems to low. Anyone know what psi I should be running at. I searched google and have gotten everything from 26 psi - 60 psi. I have no clue whats best to run at this point for on road psi. Any help is greatly appreciated!
If you have time you should do a “chalk test” on your tires to find the right air pressure. I’ve been meaning to, but haven’t had the chance yet. There are videos on youtube showing/explaining it.
 

bingo23

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275/55/20 Bridgestone Duelers to 275/70/18 Duratrac

So 275/55R20 without a 'P' in front and SL 113, and 'LT' 275/70R18 125/122 'E' ?

Each bit of info matters when calculating the new pressure. SL, XL, 'P', 'LT' etc. all make a difference. I get the calculator recommending 41 psi when using 275/55R20 SL 113 vs LT275/70R18 125/122 E.
 

bingo23

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They should be inflated to the factory recommended psi on door pillar , 36psi. tire ratings are for MAX pressure at max load, not the recommended setting for all vehicles that are running that tire.

Tire rating are for max pressure and load, but you only want to run the door placard setting if you are running the stock tire size and load rating. If you change sizes the tire will most likely have a different load rating, and when going to LT tires the pressures to carry the same load can be much different.
 

bingo23

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I'm running 45 in my Ridge Grapplers. Went from the factory 275/55r20 to a LT275/60r20.

The calculator says 46psi for the 275/55R20 to LT275/60R20 change. Have you ever done a chalk test?
 

Alxmlr789

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Lots of false information regarding tire pressures when going to an LT tire from a P metric. Definitely NOT the pressure on the placard, you'll kill both your rolling resistance (MPG) and the outside edge of your tires. Toyo made a chart specifically for this, and is very helpful.


In short, look at your OEM tire size and pressure on the door. For me it was 285/45/22 @ 36 PSI = 2416lbs. I made the switch to a 35x12.50x20, so I take that 2416 to that tire size which takes me to 43ish PSI (right between 40-45). I run the front at 48 being a little heavier, rear at 43. When i am towing, i bump the rear up to 50PSI.

If your stock tire size was 275/55/20 @ 35psi (just guessing) that would equal 2403lbs on the chart. Take that 2403lbs to your new LT275/65/20 which gives you 2475 @ 45PSI. So you'd want to give your tires 45PSI for the right load. Now you can adjust a little bit since these are trucks and not a 50/50 weight distribution, you should run a little higher in the front than the rear. Maybe 50F/45R. All depends on your gross axle weight. Every other method is really guessing, the chalk test when brand new can be helpful however can be tough to get truly accurate.

Hopes this helps.
 

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