Trans and diff gear oil

[kjphilippona]

I really need to change out the gear oil in my 5 speed transmission and differential. From what i can make out in the owners manual the transmission takes GL-4 and differential GL-5. I cant make sense of what weight oil i should use.

[kenz240z]

I can't remember the exact weights, but I used Redline gear oil in the diffy and Redline manual transmission fluid for the 5-speed in my Z.

[Jeff G 78]

+1 on the Redline. Here's a link that explains what you need.

http://www.atlanticz.ca/zclub/techtips/mtl/index.html

Most Z owners use MT90 rather than MTL for the trans and 75W90 gear oil for the diff. Don't use MT90 for the diff as it is not formulated for that usage.

Edited December 22, 2010 by Jeff G 78

[LeonV]

I can't remember the exact weights, but I used Redline gear oil in the diffy and Redline manual transmission fluid for the 5-speed in my Z.

That's exactly what I did as well. I just looked up the oil specs in the correct year FSM for my tranny (late ZX 5-speed) and matched it with Redline products at a local speed shop. I don't remember exactly, but I'm pretty sure I got the weights that Jeff mentioned, MT90 for tranny and 75W90 for the diff.

[Reverend]

I have the plans to change oils too (240z). I havent never done that to diff and tranny, so my question is: where are the drain plugs on those?

[conedodger]

Two each. Bottom is drain, side is fill.

[Jeff G 78]

Easier said that done on the diff. Be sure to remove the fill plug first. If you remove the drain plug and then can't get the fill plug loose, you can't easily refill the fluid. The fill plug is a pain to remove. Lots of heat might be needed before it breaks free.

[Bonzi Lon]

An easy way to re-fill if you don't have something to force it up & in. Take a 2 foot length of hose that will snake down through the plug hole after removing the ashtray, and into the fill hole. Pour in the pre-determined amount of fluid. Same with the diff., there is a plug near the back of the spare tire well.

Bonzi Lon

[tlorber]

Another thing that really helps is, assuming you manage to get the fill plug out, replace it with a male plug rather than a female one. That way you can get a wrench in between the cross member and the diff cover. My car has nowhere near enough room for a 1/2" drive ratchet to fit in there.

[MEZZZ]

I had this link saved for when I got around to doing the diff. I ended up removing it when I bought one of Daves R/T style mounts . Thought it might come in handy for someone else, so here it is, courtesy of Atlantic Z

http://atlanticz.ca/zclub/techtips/differentialoilchange/index.html

[kjphilippona]

Thanks MEZZZ that was very good info to know. I have made a similar mistake changing the oil in my moms Saturn, first time i drained the oil and did not have a filter wrench that would fit her oil filter. I had to drive 30 miles back into town to get a filter wrench. Second time i drained the oil and the parts house gave me the wrong oil filter, back to town for the right filter :mad:

[FastWoman]

KJ, when I refilled my R200 diff oil, I was able to squirt the oil successfully to its target with very little mess. As I recall I had to squirt over the top of the moustache bar and into the hole! Just a series of long, steady squeezes.