Yesterday, I found out what happens when water gets into the oil of a manual transmission. It’s bad. Very bad.

A few months ago, I introduced my new off-road project, a 1948 Willys CJ-2A. The Jeep ran and drove, so I thought I was in the clear. But then I went to drain the transmission.


About a quart of water came out, followed by this disgusting fluid resembling the black sticky stuff that turned Peter Parker into that evil black version of Spider-Man.

But it gets worse. The transmission shares fluid with the transfer case, which expelled this diarrhea from its drain plug:

I knew after draining those two, that there would be carnage inside, and boy was I right.

Removing The Transmission

Removing the transmission on a 70-year-old vehicle is a job I wouldn’t wish upon my worst foe. Ninety-nine percent of the job was bone simple; we removed the bolts holding the engine to the transmission bell housing (see picture above), then we unbolted the clutch linkage, speedometer cable, propshafts, transmission crossmember, and then just lowered the trans down with a floor jack.

Except it wasn’t that easy, because the shifter levers wouldn’t come out of the transfer case, so we ended up bending the crap out of the body where those levers poke into the cabin.

Still, at the end of the day, we got the transmission and transfer case out, finding that they were completely covered in seven decades worth of dirt

We unbolted the bell housing:

That left just the case. With some snap ring pliers and a hammer, we were able to extract the transmission’s internals to get a better look.

The first thing we found was this totally shot transmission input shaft bearing (there should be balls all the way around the inner race):

But bearings are cheap and easy to replace. What I was really worried about were the gears. And my worry was well-placed, because the things were toast.

First and Reverse Gear

Let’s start with the gear that got the worst of it: the first and reverse slider gear (the one in the topshot). From a distance, it doesn’t look too bad. But then you look closely, and boom:

Another angle:

Those gear teeth look like the surface of mars, with huge craters from rust and the stresses of metal-on-metal contact. But there’s more. Here’s third gear:

Third Gear

Looks fine from a distance, but just look at that pitting:

Second Gear:

Just have a gander at those pits. Looks like a freaking mountain range:

Transmission Output/Transfer Case Input Gear

This is the transmission output gear/transfer case input gear:

Another angle:


The cluster— which is used for first, second and reverse— actually doesn’t look too bad from a distance, except it’s got gigantic gaping craters in its gear teeth. Look at this thing:

So basically, my transmission is completely toast. The only thing I can even use is the case, but now I have to find all new internals. And unfortunately, it turns out, old Willys transmission parts are not cheap.


So I’m going to have to pray that some hoarder on an internet forum has too many T90 transmission parts lying around, and will sell me these gears for a song. Otherwise, I’m not sure how I’m going to make this project work.

I could just put the transmission together with new bearings, and see how long those gears hold up, but something tells me a trip to Moab would break every damn gear in that gearbox. So I’m off to the forums to beg for some cheap parts.