I have no idea if it's been worked on before. How intensive would a rebuild/parts replacement be, in terms of specialty tools, etc.
The fluid looked fine to me. No sludge or chunks, or metal shavings to speak of.
Truck is a 1989 4runner, 22re, automatic.
Lately, when accelerating quickly from a dead stop, I've been hearing an unpleasant groaning/grinding/rumbling sound from the vicinity of the transfer case, and when I put it in 4L it makes the same sound (but worse), and keeps popping out of 4L.
I...