Is this beyond hope?

[Shayne]

60 years of poor drivers have taken their toll. Besides the mess at the mesh points the box is in very good condition. Sigh.

[Bob Carriere]

At least all the teeth are still there.... previous owner probably didn't like to double clutch........

You could try to dress up the meshing end of the teeth to be round like the oiginal configuration BUT you will be removing more metal.....

Why don't you ask around for a new or almost new or better than yours on the Forum....... the hard parts to find on a CMP tranny is a good housing that has both the bolting ears still in one piece... and the proverbial rear cover which usually suffers from what we call a "Mooney job" after the early article on why back covers get broken....... gears are usually still very good..
Early tranny rear covers were white metal....very soft and fragile..... usually recognized by the machined speedo cable port and fitted with a threaded plug. The more sturdy model is the later ones cast of iron and the speedo port is blank and not machined at all.

Your biggest problem will be the shipping cost for the shaft...... ask around on the West coast .

If you really get stuck I think we have some in the barn.......

How are the tranny bearings...?? they are available and now is the time to replace them if at all necessary....... remember all the metal missing on the gear teeth must have been floating around for some time...

Bob

[Keith Webb]

Is your gearbox Ford or Chev?

It's only the Chev gearbox casings which suffer from the "Mooney job" Bob describes.

For all the abuse these gearboxes suffer they are very strongly built and when you find a wreck it's usually wrecked because of engine problems rather than gearbox.

The gears shouldn't be hard to find - I'd be doing that rather than using that one given the pain in replacing it later - especially if it is a Ford.

Amazingly the gearbox in the attached image turned out to be mostly OK despite appearances - you can see it in this gallery.

[Shayne]

It has the alloy rear cover and it is perfectly fine.
The reason I pulled it and opened it up was to rebuild it but I am not interested in swapping out gear sets. Bearings are quite enough.
So I'm going to a T19 because I have one.

[Bob Carriere]

Tranny picture reminds me of the Chev tranny I removed while the engine was suspended from the bucket of the tractor.....made it easy forme to reach underneath and remove the two largebolts that holds the tranney to the bellhousing and can only be reached form the underside.

Never occurred to me to check for any liquids inside..... first bolt came off and at least 2 liters of clear water poured out..... not to concerned to get out of the way its only water..... but all the tranny black thick oil was floating above it......... needless to say I was well lubed.

Even with all that water inside the tranny it seems a lresidual light coating of the black tranny fluid remained on the shafts and bearing and all was salvageable after years of soaking...... they sure build them well in those days.

Bob

[Shayne]

What is the tranny called? I have a 420 and it isn't the same as that.

[Grant Bowker]

I don't know of the CMP Chev transmission having a name, it was simply the 4 speed truck transmission.
For a while I was looking at trying to find a SM420 to put into my C15A. In the end I decided it wasn't worth the effort. Although the SM420 is compact by today's standards it is still quite a significant bit larger than the CMP transmission. Putting one in would mean either shortening the already short driveshaft between transmission and transfer case or moving the transfer case and as a result the mounting crossmember and shortening the rear driveshaft. Life would be simpler for someone with a 2 wheel drive CMP, only one driveshaft to shorten.