Does anyone have the specs for the brake drum minimum size ? I now have the repair manuals and there are no specs listed

google search the part no. check the results looking for a national stock number data listing. i have found the measurements for gears for my d4 that way.

you could also check the cat parts sytem at parts.cat.com or call your dealer and ask they may have the info. the service book should have the specs.

I google just about everything and it's how I find my parts . I've yet to find specs though

There are no specs for those or limits as to turning them, I wouldn't remove any more than an eighth of an inch of material. For safety reasons, working on the hills, if it was mine, I would just replace the drum.

as Rome says, don't remove more than an eighth inch of material, that's quite a bit of material on a large drum
-remove the absolute minimum it takes to clean it up
-is there a section of the drum that is not worn that would give an indication of original diameter?
-surprised nobody can find that number somewhere?

You could measure the thickness of the opposite side drum if thats good.

I've never been into a D8, but the clutch drum assembly on my old D7 was plenty heavy. On the D7 the brake band came apart in three pieces. For some reason I cannot recall, the drum had to be installed first and the brake band put back in in three pieces and bolted together. Anyway, I fashioned a piece of about 4" belting with Dee rings on the ends so I could catch that drum and pull it up out of the housing with a come-along hoist. The more I thought about losing that hunk into the bottom of the case, the nervously I got!

Just a suggestion. The shop book probably has better ones.