The GMC CCKW

Can anyone post some pictures of the gearbox diagram from TM10 1563 or any other publication. My father in law is rebuilding a gearbox and needs a bit of guidance of what belongs where.

Thanks in advance

Hi Nige
I'm not familiar with your manual reference but assume the gearbox you want the info on is the five speed Clark as used in the CCKW.
PM an e-mail address to me and I can send photos of the relevant page/s.

David

I sent the images a couple of days ago Nigel. Did they arrive or have they wandered off somewhere?

David

Dave
do you know if the studebaker US6 clark (or warner) gearbox are completely interchangeable with the cckw ?

further on gear boxes ( and transfer cases) - can you tell me where the breather vent is - is it the same as those on the axle housings?

The differences are bolt on and you can convert one to the other if you have the right parts. So, no, the gearboxes do not interchange directly.
The major difference is the input shaft which on the U.S.6 is about twice the diameter of the CCKW. It uses the same bearings but of course needs a matching retainer to the shaft. The retainer also carries the clutch throwout bearing which is completely different between the trucks.
Other differences are the gear lever, the Stude lever is more upright than the GMC lever which is bent back quite noticeably. ( as an aside, this difference adds to the tendency for the lever in the GMC to slog out its anti-rotation slot and loosen the peg in its hole(.
Other differences are more minor and mainly relate to the use of studs and nuts in place of bolts.
The five speed Clark or Warner didn't use a dedicated breather to my knowledge. I always assumed that they breathed up around the gear lever.

David

Thanks David
thats exactly what I needed