40C final drive: internal leak?

I've learned a lot from this forum but this is my first post. If this question has already been answered somewhere, I apologize; I searched but couldn't find anything.

I have a John Deere 40C crawler, 4-roller. It's my first tracked vehicle, but not my first tractor. The serial number plate is missing, but the previous owner claimed it's a 1955. He also said it sat for "a few years"... I know we've all heard that one! I bought a factory service manual, which says that the steering clutches take 1 3/4 pint of SAE 90. I opened the fill plug on the right hand steering clutch, and to my surprise, oil poured out of it it (and also the drain plug), more than a quart total. It does not look milky. While I was under there, I noticed a mysterious drain plug on what I believe is the bottom of the final drive. It was finger tight, and when I removed it, nothing came out.

Try as I might, I can't figure out what that drain plug is for! It appears in a few photos and diagrams in the manual but is never named. The lubrication chart seems to say that the final drive takes some grease but no oil.

So, before I tear into this thing, my question is: why does the steering clutch have way too much oil? The previous owner couldn't have overfilled it, unless he jacked one side up or parked on a steep slope; where could that oil have come from? Is there a seal between the steering clutch and something else that commonly leaks?

I was facing forward when I took the photo.

There should be two of those plugs, one under each clutch housing, they allow you to drain any water that gets into the housing.

Ah, that makes sense! Thanks for the quick response, Bob. I guess I'll put some oil back in the clutches and move on. I'll check the level again in a few days.

I would sure think the steering clutches are a dry clutch. I know the 440 crawler is. The final drives would take a little gear oil in each side.

I probably have my terminology wrong, Mike... the lubrication diagram in the manual says that the steering clutch takes 1 3/4 pints, but the chart on the page before says the FINAL DRIVE takes 1 3/4 pints and says nothing about the steering clutch.

The fill plug in the first photo is the only place where I can add oil, so whatever that thing is called, that's where the oil is going!

From reading other posts, the consensus seems to be to use 85W140 unless you're running in extreme cold; it does get pretty cold here in Maine, but I park the 40 all winter (plowing snow while wearing goggles was fun the first time, but once was enough).

(quoted from post at 02:04:04 06/17/16) I would sure think the steering clutches are a dry clutch. I know the 440 crawler is. The final drives would take a little gear oil in each side.

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ust helped rebuilding a 40C earlier this spring. Mike is correct, the steering clutches are dry. The final drives are what you are looking at. In addition the other plug is a drain for the rear end/ transmission, the fill location is on the rt side foot board area. A complete parts break down is available on the free JD parts web site, Catalogue # 862 40 Series Tractor.

The string cluch are dry and yes the final drive need gear oil

I have a 40c and the clutches are supposed to be dry and the final drives(big roundish
castings) has the gear lube in them.

Thanks guys, I put oil in the final drives and it's crawling once more.