Got mixed up on the D2 drain plugs is there a schematic?

I fired up the D2 last week and it started up right away. The plan was to move it to a good location to get underneath and drain my clutch compartments. This had been done since I bought it in 2010 and I probably put twenty hours on it since. Last summer it started to slip (or something) when it got warmed up, you'd stop on a small incline and engage the clutch but no movement. . .

This is serial no. 4U23XX we're talking about.

Embarking on a full maintenance per the CAT operators manual, I first loosened the large inverted hex nut to drain what I thought should be the main clutch. Gear oil gushed out instead and after about two gallons I put the plug back in place. I moved further under the machine to the more forward nut (closer to leaf springs) which was the correct one. Out gushed about a gallon of water followed by lots and lots of black greasy sludge and it drained slowly for awhile.

Then came the steering clutches and not much at all came out of these. I had to double check the manual as to which square plugs were the steer clutch drains. There are a pair of drain plugs (one small, one large) on both sides of the transmission - does anyone know what these are for? I didn't find anything in my manual. Also, there are plugs all over under this D2. Is there a diagram somewhere identifying each plug?

Your clutch compartment should be dry for an early 4U, that could be part of your slipping problem. I'd put the plug back in and flush it with kerosene or diesel and drain it again. If necessary, adjust the clutch tighter a notch or two and see if that helps.

These pics ought to help.....

I thought those two in the middle of the second photo were for the bevel gear compartment, as distinct from the main transmission. So basically the steering clutch compartment has two plugs per compartment?
Cheers,
Neil.

Yes, there are two drain plugs per steering compartment due to a re-inforcing web in the casting. 👍

Thanks Rich and Old Magnet for the info and pictures - very much appreciated! Like Rich had explained, once I emptied all the water/sludge out my slipping problem is completely gone. I even tried removing a large Pine stump by pushing it on an uphill part of my new trail and although I couldn't get a good/safe position to work the stump, my tracks churned in the dirt when the blade stopped up against the stump. That's alot of power in my opinion. Working on the incline wasn't a good idea and I'll work it later with a chain.

I do lots and lots of searches to find answers to most of my questions but the assistance you guys provide when I'm stumped (ha!) is priceless. Thank You. Love my CAT.