I am not sure what weight gear oil to use anymore since its been a long time since I did those. I used Mobil 1 full synthetic in my rear diff, huge improvement over the 17 year old gear oil that was inside. I recently checked the rear diff and the fluid is still really clean. <img src="/forums/images/graemlins/kewl.gif" alt="" /> I would have the local parts guy look up the appropriate fluid for your particular Gen1 unless one of the 4cyl guys chime in with the answer. <img src="/forums/images/graemlins/cheers.gif" alt="" />

Richard E
1989 Montero - Stock-ish
1989 V6 Auto Raider - 5.3 Vortech Swap.
1987 Mitsubishi Starion 2.6t, soon to be 3.5
1983 Honda XL600R