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Optimal tire pressure for 39.5's

Discussion in 'The Garage' started by tRustyK5, Sep 27, 2003.

  1. tRustyK5

    tRustyK5 Big meanie Staff Member Super Moderator GMOTM Winner Author

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    Optimal tire pressure for 39.5\'s

    After reading Grimmy's post on tire pressure theory I figured I'd try it out for myself with my new swampers.

    Ambient temp was 78 F, ran down the freeway at 65 mph for 20 miles and then pulled off into the scales to check tire pressure before they cooled down.

    For those that don't remember The guy Grimmy talked to was some tire expert and said with optimal tire pressure the reading should rise by 10% and no more when hot. I baselined the tires at 23.5-24 psi and when I checked them hot they were 26.5-27 psi. I'd think that's pretty damn close to ideal pressure for my truck.

    We'll see how they wear I guess, at least I got farther than 3 miles before blowing one this time /forums/images/graemlins/smile.gif

    rene
     
  2. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Re: Optimal tire pressure for 39.5\'s

    I've got 20 in my TSLs.

    Ideal trail pressure seems to be about 8 psi. /forums/images/graemlins/smile.gif
     
  3. willyswanter

    willyswanter 1/2 ton status GMOTM Winner

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    Re: Optimal tire pressure for 39.5\'s

    I run 45 in mine on the street and around 5 or so on the trail...
     
  4. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Re: Optimal tire pressure for 39.5\'s

    45? My 38s max at 25, I can't imagine a set of 39.5s being much different.
     
  5. Shaggy

    Shaggy 3/4 ton status

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    Re: Optimal tire pressure for 39.5\'s

    Jason has the E rated tires so his are kinda different.
     
  6. 84_Chevy_K10

    84_Chevy_K10 Banned

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    Re: Optimal tire pressure for 39.5\'s

    E rated 39.5 TSLs?
     
  7. bigjbear

    bigjbear 1 ton status Staff Member Moderator

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    Re: Optimal tire pressure for 39.5\'s

    39.5s come in 6 ply rating or 10 ply rating.
     
  8. mudhog

    mudhog THEGAME Staff Member Super Moderator

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    Re: Optimal tire pressure for 39.5\'s

    rene i run 23 psi in my 38's and have run them for almost 2 years and the tire wear has been nice and even /forums/images/graemlins/thumb.gif
     

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