I have just bought a Cat grader serial # 9T3585. The rear tires are shot and are 10.00x24 grader type tires. 10.00x24 tires are next to impossible to find and my 212 parts manual says the rear tires should be 13.00x24.
13.00x24 inch tires are much more available but in looking at the difference in the listed dimensions, it appears to me that the 13's will rub the raised portion in the center the chain housing. That is if there is enough room to mount them at all.
Anyone out there that knows if my book is correct about what tires this model/serial # grader takes?

The specifications I have show 10.00 - 24 for the rear tandem.

The 10.00 x 24's were correct at the time the grader was manufactured (1953), but this size became officially obsolete in the mid-1950's as tire manufacturers standardized on a lesser number of sizes.

If you acquire some later parts books, and compare the individual wheel hub/rim part numbers and drawings .. you'll find that either the rim pressing or the wheel hubs were modified in design, when Cat changed over to the 13.00 x 24 tire size.

From late 1955 to mid-1956, Cat changed over to tubeless tires on all motor graders, wheel tractors, scrapers and wagons. The new tubeless tires required a new three-piece rim with an o-ring seal.
Earlier model graders, wheel tractors, scrapers and wagons could be retro-fitted with the new tubeless tires, but the new tubeless rims were required as part of the deal.

You will likely find that the newer rims or hubs have a bigger offset to compensate for the wider tires. The changeover to tubeless tires on the 9T series motor grader came in at S/N 9T4762, in Dec 1955.

I recently found that Denman tires makes the 10 24's. Check it out. I think Goodyear makes a 12 24 thats a little fatter, might have to widen the rims for them. Good luck and hope everyone had a good holiday. Charlie

"dinasnore" wrote:

I have just bought a Cat grader serial # 9T3585. The rear tires are shot and are 10.00x24 grader type tires. 10.00x24 tires are next to impossible to find and my 212 parts manual says the rear tires should be 13.00x24.
13.00x24 inch tires are much more available but in looking at the difference in the listed dimensions, it appears to me that the 13's will rub the raised portion in the center the chain housing. That is if there is enough room to mount them at all.
Anyone out there that knows if my book is correct about what tires this model/serial # grader takes?

Thanks to all for the info. You just saved me buying an expensive set of 13 inch tires.
Mike