advice for Diff oil change?

[crazspence]

gonna get a chance to work on my car tomo so im gonna change out the diff gear oil and whatever else that needs to be done. im gonna bet that the previous owner hasnt changed the oil on it. any advice on what to watch out for while under the rear axle? i know you gotta undo the filler plug first before you take out the drain plug. but besides that, anything else?

[Milton'Z Nissan'Z]

Nope, just drain the oil and fill 'er up with something good. I prefer Royal Purple but there are other good one's too. If yours is a manual trans, do it at the same time. Red Line MT-90 is superb. Makes it shift smooth and in some cases eliminates any slight grind when upshifting.

[es.biggs]

Don't get any on you it stinks like nothing else

[crazspence]

finished the oil change bout 30 mins ago. when i saw the oil that came out, it looked like it probably hasnt been changed since it first rolled off the assembly line. =/ well i replaced it old oil with mobil 1 75W-90 full synthetic. hopefully ill feel a difference. and uhh about my MT, i havent found a store near me that sells redline MT-90 and i didnt want to use any of the other stuff they have since its all API-GL5 while the FSM suggested that you use API-GL4 oil. does it make a difference at all?

[robomatic12]

Yeah big differnce, we need the older stuff so it doesn't eat up the syncros. Grab the redline mt90 for your 5spd, even if you have to order it somewhere

[es.biggs]

A lot of specialty repair/tuning shops can get MT-90 for you...or you can order it online. Even ebay probably.

[car nut]

I have NEO Full Synthetic 75w90 in my 5spd and it shifts like butter. Never tried MT90 but I doubt it's better than this.

[vulcanrush]

car_nut, 75w90 is for the diff, mt90 is for the trans, right?

[car nut]

car_nut, 75w90 is for the diff, mt90 is for the trans, right?

75w90 is the recommended viscosity for both the diff oil and the trans oil. MT90 is a brand made by Red Line Synthetic Oils.

[vulcanrush]

thanks, car_nut, i didn't know mt90 was by redline only.

i learn something everyday.

[CrazedZ32Owner]

if im not mistaken Z1 sells redline mt90...... probably WAY overpriced tho