I have a 1988 toyota 4runner. Does the transmission and transfer case share the same gear oil? Or are they both separate units?

 

yes, they share fluid, if its an auto, ATF in the tranny and X-fer if its a manual then gear oil in both, 95% sure anyway

 

they are different oils

 

Guess I should of listed its a 5 spd manual tranny

 

manuals take the same oil as the gear driven t cases but they are sealed between the 2. there is a seal on the output shaft of the transmission.

 

and if the seal goes bad, all the transmission oil gets pumped into the t-case and leaks everywhere from out of the shifter hole, and the input shaft bearing on the w56 takes a poo, and leaves u stranded on the side of the interstate. but the good news u can drive 10 mph down the side of the road and make it to the shop to replace the transmission on a holiday weekend... Ask me how i know...

 

they dont share the same fluid. These use the same fluid. Separate "containers".

http://www.ncttora.com/fsm/index.html

go here and scroll down to your vehicle and download

 

wow u only went 10 mph? I drove out of the mountains the whole way across town and then back again to my house about a 30 mile round trip with absolutly no fluid in my trans and was going the speed limit or slightly over (up to 50 mph)... Didn't know I punched a quater size hole in the bottom of it while wheeling in the dark. Was wondering Why it was starting to whine coming out of the mountains. still works flawlessly a year later after jb welding it shut and filling it back up. heres a pic to prove it.