Triumph Repair: 1970 type D overdrive unit

Question
I'm in the process of rebuilding a type D overdrive that I bought off e-bay. The unit was in good shape I'm just cleaning it up and replacing seals and bearings. The clutch faces look good but I don't know the extent of wear. Do you by chance know the thickness when new and when they should be replaced.

Answer
Hi Tom,

I could not find any specs on the original thickness of the lining. If you can find a supplier of the clutch cone you may get them to measure it for you.

Another option is to use the manual's direction to check the shimming clearance which might lead you to a conclusion on the amount of ware if it is not obvious to look at.

Rebuilt a few many years ago in dealerships but don't remember measuring the lining thickness.

Howard