Looking at a used 3rd Gen 4runner, trade-in at dealer, in great shape but no records from previous owner of differencial fluid changes, transfer case fluid change, or tranny oil change (5speed). Oil has been changed regularly.

Should I be concerned?

Are there any ways to tell if it has been done? Owner doesnt remember.

 

My biggest concern would be the auto tranny fluid and other problems associated with the auto tranny, but you don't have to worry about that.

I would just change all the fluids as a precaution. Check the coolant and the hoses. If hoses are weathered and cracked, it's a good sign the coolant hasn't been serviced, at least by a dealer. If the coolant is red, it is OEM Toyota. If green, it isn't and shows it has been changed by someone other than the dealer.

Change diff fluids, tranny fluid, check the power steering and brake fluid. Grease up the zerks on the drive line and u joints. Check the ball joints and tie rod ends for play and corrosion, and consider replacing.

All this is fairly inexpensive and will ensure more life out of your 4runner if you do buy. Good luck!