3 speed Trackmaster bulldozer transmission

Dfab Bulldozer Restoration PArt 5: Transmission and Hydraulic motor

#60 chain drive off of the 3 speed transmission on my Dfab Engineering Trackmaster Dozer

The first thing I wanted to do, was work on the transmission. Now from these photos you can see pretty clearly that there is a lot of grime, grease and gunk in the belly of this beast. I started by removing with steel scrapers as much of this as I could possibly remove. I took almost 4 gallons in 1 quart containers out by scraper. It was nasty oily gunk mixed with mud and leaves.

yes, nasty cigarette butts in the gunk that is several inches deep on tiny dozer.

Another angle of the transmission, and more of the nasty

close up of the transmission. Notice the top isn’t sealed/closed.

Now part of this restoration project was knowing that the transmission was broken. It’s stuck in it’s mid gear (didn’t know which gear it was at the time) which provides roughly 4.5:1 input: output reduction. The other two speeds are about 1.5:1, and 18.5:1. The low gear in this transmission at 18:5:1 must be feircely slow, because the middle gear is not fast. Anyways, Note the top isn’t attached, and seeing the condition of everything else I feared this would be beyond salvage.

there are three connections to the hydraulic motor, two -10 SAE male JIC and one -4 male JIC (case drain I believe), along with 4 bolts in sliding slots (to allow tensioning of the chain)

Removal of the transmission required some funky bending of my arm to get at all of the nuts. There are 4 all metal lock nuts used to hold down the transmission. The bolts are welded to steel flat (will add a photo eventually) and slide in slots for tensioning of the chain. There was likely a chain guard at some point, there are spots that look like welded steel taps broke off in the correct locations for a chain guard. Additionally there are three connections to the hydraulic motor, two -10 SAE male JIC and one -4 male JIC (case drain I believe).

After loosening the transmission you can pull the chain off. I piled mine over on the rear drive assembly.
While this is heavy, it’s not impossible to manage. I lifted it out by hand, I’d guess it weighs in with the motor attached at 150 lbs

The transmission lifts out relatively easily after disconnecting it from the chasis and hydraulic systems. I used some hydraulic JIC caps and plugs I ordered as a kit to close off the system on the tractor side. This will ensure it doesn’t get any contamination in the fluid causing wear or damage in the future.

In the main shop, ready for some serious TLC

The removed hydraulic motor and transmission assembly. In the next post I’ll show photos of the dissassembly and problems discovered on this part of the Trackmaster crawler.

If someone stumbles across this page with any information about these Dfab Engineering Trackmaster Dozers Crawlers, I’d love to know more. I’d be happy to host manuals and or parts catalogs here on my blog if you have them and are willing to share them with me. Please leave me a comment or email me at my website name on Gmail (no dot com there). I don’t check often, but I eventually will get back to you to host the information. Thanks!

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