Is your shifter feeling notchy? Are you hitting up those track days and cooking stuff up? Or just doing general hooliganism? It may be time to do a flush of your gear oil. Otherwise the scheduled maintenance is trans: 24 months or 30k miles, diff: inspect 12mo/24k, replace 48mo/60k.

You’ll need a 10mm hex tool, some gear oil, and some gaskets. The gear oil should be 75w90 and you can use the same oil in both the diff and the trans; you’ll need 4 quarts for both. It’s 2.2 quarts for the trans and 1.1 to 1.2 quarts for the differential. Motul oil is nice as it comes with a long neck to help get it in there. A pump is probably easier given the amount of available space to maneuver in the 86 platform, although there is enough to do this task using the Motul bottles without one.

Additionally you’ll need some gaskets. Part numbers and torque values are as follows:

PartPart #Cost (ea)Torque N-mTorque ft-lb
Differential fill plug gasketSU00300122$1.944936.1
Differential drain plug gasketTOY1215710010$1.504936.1
Transmission fill/drain plug gasketSU00303626$9.723727.3

The reality is the diff fill and drain plug gaskets are the same crush washer. Some people flip and reuse them; no thanks – I bought some new ones. The transmission uses flat washers and are ok to reuse. They are quite expensive as well. Most of this stuff can be found on Amazon. You can get a 3/8″ or 1/2″ drive for the 10mm hex, I don’t think my diff fill plug was overtorqued when the fluid was replaced last, but it was a bitch to get off.

Shout out to this dude who seems to fuck up more shit than I do in the garage, although probably fixes his way through it a lot better than I would! Some videos showing both the diff and trans. Also – no joke that this stuff is stinky as hell. It doesn’t smell great going in but boy is it stinky coming out!