Hi, all.

Figure while it is unbelievable hot outside, it's a good time to change the oil in the t'case. The previous owner never touched it, and I doubt it has seen much, if any, maintainance in it's 27 years of life. Not having any problems with it, but like to head those off early.

According to my Chilton manual, to drain the oil from a NP203 t'case (full-time, chain drive), I'm supposed to remove the lower bolts from the PTO cover (which I'm assuming is the sheetmetal cover on the passanger side) and the rear cover of the front output shaft (back, drivers side). The Haynes manual just says to drain it, but doesn't say how.

With just pulling out a bolt from each cover, will I need to replace the gaskets for these covers? The PTO wouldn't be a problem to replace, but that rear cover on the front output holds the bearing seal for that output shaft, and I don't really want to pull the whole thing apart just yet. I'm thinking the gaskets will be okay, and if they start leaking, I'll know I was wrong. Any help would be great.

Also, I'm planning on filling the t'case with 4 1/2 quarts (9 pints) of synthetic 10W40. The Chilton and Haynes manuals both say 50W warm/30W cold, and that's fine for an NP205, but anything aftermarket I have found on the NP 203 says 10W40. The filler plug, about 1/3 of the height of the t'case from the bottom, right between the rear output housing and the rear cover, is easy enough to find, though I'm not sure of the best way to pour all this oil in (any suggestions would, agian, be helpful). I was told that if the seals are okay, the synthetic oil would work just fine. The seals don't seem to be leaking, so I think the extra cost of the synthetic oil will be worth it to be nice to a most likely neglected t'case.

Since it can't hurt to check the axels while I'm under there, would there be any ill effects from using axel lube with limited slip additive in an axel without limited slip? Not really sure what's in those two pumpkins, but I doubt they are anything more than regular differentials. Still, without knowing, I'd rather play it safe and add the altered lube. All the text I can find says 80W to 90W for axels. Is that correct?

If anyone has any suggestions, advice, and especially experience, please let me know. Thanks so much.

Matt