Some stuff is different, a lot of it is the same. I sold my 01 Tacoma and bought a 00 4Runner just so I could swap a lot of my aftermarket parts over. CV's are the same (if both ADD), lower control arm, upper control arm, knuckles, ITR, steering rack, UBJ, front diff, etc. Front driveshaft may be the same depending on trans/transfer case setups of both veh's, a tape measure can confirm. Rear driveshaft is probably different. LBJ and OTR are different, but can be swapped out together. Rear ends are set up different, but the diff's are interchangeable if they both have the locker. Wont be interchangble if the runner is an open 8" and the Taco is an open 8.4". Lots of little things here and there too.