5.7 L 350 Vortec V8 Gas 99 GMC Yukon. 4WD. Verified transmission: 4L60E w/ deep pan. In '07 i had trans mission re-built (maybe not important) and so...I am replacing a solenoid inside the transmission pan/driver's side. So i must remove pan. NO DRAIN PLUG. NO PLUG Anywhere on the pan. I see the divot where the drain plug should be however no plug has been drilled, it is a smooth divot. Could this be? Could this be a new pan the mechanic put on? What gives? Any clues on where a plug would be? How do I drain then? Di I drill hole and plug later? Can I just loosen pan? Will 8 qts of Tran fluid dump everywhere? I loosened the plug on the rear transfer case and about a cup of milky red substance poured out and that was all. This can not be trans fluid..? Not near enough, however must I replace this fluid? With the blue or red transfer case fluid? Please help soon...drain plug issue most important.
Transmission drain plug on 1999 GMC Yukon
by Reagan in Vancouver, WA on January 15, 2010
ANSWER by patrick mannion on January 17, 2010
I have seen transmission pans with no drain plug (and radiators with no drains), seems like a stupid way for the manufacturers to say a dime. The pan is not thick enough to drill and tap but I would drill the pan and bring it to a radiator shop and get them to braze a nut in place to accept a drain plug for future ease of maintenence.