Tire size on a 4wd

Rodeo man · Aug 12, 2018

Got new tires all the way around my loader tractor. Was careful to buy the same size I had. Although the same size (12.5/80-18), the fronts are noticeably taller than what was on there. What issues if any, is this going pose? I have only ran the tractor in 2wd since getting the tire.

JD Seller · Aug 12, 2018

If they are the same brand front and back are the new rear tires larger too??? If not check the air pressure. Smaller tires can change diameter with higher pressures.

Put your tractor in 4 wd on lose gravel or dirt. Drive straight while not pulling anything. Roll to a stop and then look at the tracks. If the ratios are out you can see scuffing in the tracks that are left.

Texasmark1 · Aug 13, 2018

"Put your tractor in 4 wd on lose gravel or dirt. Drive straight while not pulling anything. Roll to a stop and then look at the tracks. If the ratios are out you can see scuffing in the tracks that are left."

And the direction of the scuff tells you whether the fronts are pulling, aka too large in circumference, or getting pulled, too small in circumference. For non-math folks, circumference is 22/7 x diameter....actual outer diameter of tire when being used not spec'd on the sidewall. An error exists in this in that for some tires run at low pressures, the ground contact part of the tire folds up into the air chamber so that the rolling circumference is smaller than the static circumference that exists when the tire is inflated to max stated pressure, uninstalled on the vehicle. Have to figure out how you are going to deal with that.

Tire size on a 4wd

Rodeo man

Member

JD Seller

Well-known Member

Texasmark1

Well-known Member

Similar threads