Motor grader tire pressure rule of thumb?

Hey Dan, the #14 motor grader book calls for 45 psi max for 14x24 10 ply tires and 55 psi max for 12 ply tires, I'd say 30-40 psi would safe for now.

Hi Team,
from my No12, 8T--80C Motor Grader OMI is the chart that OM mentions above.
Form No 10492-9, Dated 11-57.
Hope this helps.
Cheers,
Eddie B.

edb Thanks so much👍

Hi, Folks.
A couple of pretty major contractors with whom I worked back in the 1960s and '70s had adopted a policy of running varied tire pressures in the drive tires to help stop what was sometimes called 'elephant walking', rocking from side to side when grading in higher gears.

What they did was to have a 4 - 5 PSI difference in tire pressures between the front and rear tires but with DIAGONALLY opposite tires equal. That is to say that the front tire on one side would be 4 - 5 PSI higher than the rear tire while the REAR tire on the other side would have the higher pressure.

Don't ask me HOW it worked but it did seem to work, especially with radial ply tires like Michelins. It did not completely eliminate the behavior but it did seem to reduce it.

Just my 0.02.

On my 112, which is a bit lighter than the Model 12, I run 35 psi in the front and 30 psi in the tandems. 13 X 24 Tires. Still get a heck of a bounce in road gear after it sits for a couple days.

[quote]On my 112, which is a bit lighter than the Model 12, I run 35 psi in the front and 30 psi in the tandems. 13 X 24 Tires. Still get a heck of a bounce in road gear after it sits for a couple days.
So that's what that thump thump thump is ? LOL

I find it hard to read bird poop
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Pretty sure that reads "darn, I missed...." : )