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Tire Size and ABS

May 18, 2020, 10:30:16 pm

I am thinking of putting Michelin 295/80's on my front axle and leaving my 295/75 Toyos on the drive and tag axles for a couple more years. The 295/80 is 1.2" more in diameter. Will this size difference impact the ABS system? My front axle weighs 12,650 lb.

I am putting the 295/80's on so I can run lower pressure than the 115 psi I am running on the front now.

Thank you

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Re: Tire Size and ABS

Reply #1 – May 18, 2020, 10:42:17 pm

Ed, it will be fine but will the larger tire fit in the wheel well and not rub on air spring mounts.  On my 40, 295 75R/22.5 just barley fit without rubbing.

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Re: Tire Size and ABS

Reply #2 – May 19, 2020, 09:43:09 am

I think 275/80 is all that will clear if you want a 80 series tire.

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Re: Tire Size and ABS

Reply #3 – May 19, 2020, 11:18:09 am

   Fit is close on the front when going up one-grade using TOYOs.  For my last tire renewal, I decided to move up two tire classes.  This considerable increase required a broader tire in front, which provided more room with the airbag base than before while increasing load capacity.  When my brother saw this new tire, he said, "That belongs on a firetruck."  (He is a retired firefighter and was a "lead driver.")  He liked the idea of oversized tires because I do not carry a spare.
    For twenty years, I have run on tires that easily carry any load asked.  Because I live in a rural area, I buy my tires online--have them delivered to a local tire shop.  This little shop has no way to balance these truck tires.  I use beads to balance.  I also bring cardboard with me to protect the aluminum wheels as they work on the mounting of these tires and remind them of the "reverse" nuts.  The larger tires in the rear will decrease the indicated speed by 5% of actual.  Be fully "aired" before moving.

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