Changing the Differential / Transmission Oil
ya, after reading through i found that. I just ordered MT90 for mine. It's mostly a track car anyways and I will have it stored for the winter.
hey guys im new to the z and my z has 30k on it now and i wanted to do the transmission and differential flush. ive read a few pages of this thread but very confused. ive always used royal purple so is it ok to just use the royal purple 75-90 in both the tranny and diff? do i need any additives in either one? how many qts does the tranny hold and how many does the diff hold? my car is 6spd. thanks so much guys!
about 3.5 quarts trans, almost 2 quarts diff. He lists that in the first post with the DIY.
I did this last thursday. MT90 in the trans and redline gearlube in the diff. I'm surprised, it actually does go into gear smoother now. There isn't a huge magical change but it does seem to help. I went to the dragstrip friday night and slamming through the gears was cleaner. It took away some of the anxiety i have about not getting it into gear when i'm shifting WOT.
I did this last thursday. MT90 in the trans and redline gearlube in the diff. I'm surprised, it actually does go into gear smoother now. There isn't a huge magical change but it does seem to help. I went to the dragstrip friday night and slamming through the gears was cleaner. It took away some of the anxiety i have about not getting it into gear when i'm shifting WOT.
I've read through the entire thread. Thanks a lot to everyone that contributed.
One point, the OP mentions torque values that are different between the Diff and MT fill and drain plugs. The 2006 FSM list 25 ft-lb as the proper torque value for the drain and fill plugs for both the diff and the MT. Must have been a change somewhere long with model line.
One point, the OP mentions torque values that are different between the Diff and MT fill and drain plugs. The 2006 FSM list 25 ft-lb as the proper torque value for the drain and fill plugs for both the diff and the MT. Must have been a change somewhere long with model line.
Update, I have been using Amsoil in my Nismo diff and not having too much luck. I have read alot of post about using Motul to tame the Nismo. Just picked some up from Forged Performance and hopefully this weekend or next get it in. My car is beat on alot, so I understand why I have to change my diff fluid more frequently, I heard that Motul will quiet down the Nismo better than Amsoil. I still use Amsoil in everything else and have for about 10 years, I basically have everyone of there products in everything in my house. Just a little disappointed in there diff fluid, not lasting real long and not quieting down the Nismo diff at all. I did add the additive to the Amsoil, really didn't do much in my opinion, I would not recommend it.
Update, I have been using Amsoil in my Nismo diff and not having too much luck. I have read alot of post about using Motul to tame the Nismo. Just picked some up from Forged Performance and hopefully this weekend or next get it in. My car is beat on alot, so I understand why I have to change my diff fluid more frequently, I heard that Motul will quiet down the Nismo better than Amsoil. I still use Amsoil in everything else and have for about 10 years, I basically have everyone of there products in everything in my house. Just a little disappointed in there diff fluid, not lasting real long and not quieting down the Nismo diff at all. I did add the additive to the Amsoil, really didn't do much in my opinion, I would not recommend it.
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Joined: Aug 2009
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From: Fort Worth, TX
I've read through the entire thread. Thanks a lot to everyone that contributed.
One point, the OP mentions torque values that are different between the Diff and MT fill and drain plugs. The 2006 FSM list 25 ft-lb as the proper torque value for the drain and fill plugs for both the diff and the MT. Must have been a change somewhere long with model line.
One point, the OP mentions torque values that are different between the Diff and MT fill and drain plugs. The 2006 FSM list 25 ft-lb as the proper torque value for the drain and fill plugs for both the diff and the MT. Must have been a change somewhere long with model line.
You're probably fine. Leave it alone. I tightened those bolts to "arm tight" on my natural torque wrench. I have three settings: hand tight (5-20ft/lbs), arm tight (20-50ft/lbs), and body tight (80-100ft/lbs) lol.
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Joined: Aug 2009
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From: Fort Worth, TX
I ended up early this morning jacking it back up and loosening the plugs and retorqued to the specs of 25 ft lbs. It was buggin me so I had to do it.
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Joined: Aug 2009
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From: Fort Worth, TX
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Joined: Dec 2006
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From: Dallas, TX
Changing Diff/Trans Fluid.
I added a pic of the transmission because it almost the same procedure.
Tools Used
10mm Allen Wrench
Drain pan
Floor jack
Four jack stands or a lift.
Suction Pump/Gun. I bought mine from Advanced Auto for $10.
Harbor Freight has one for $4.99.
Rags
Replacement oil 75W90 about 2 quarts. About 4 quarts for transmission.
Two replacement crush washers.
Update:
Adding the requirements as stated in the 2003 Service Manual
Transmission API GL-4,Viscosity SAE 75W-85
Differential API GL-5, Viscosity SAE 80W-90
Procedure
1. Make sure wheels are blocked.
2. Raise and support car making sure that it is as level as possible.
NOTE: It is better to drain the fluid when it is warm so it flows easier.
3. Using 10mm allen wrench, loosen drain plug and allow diff to drain.
4. Wipe off excess oil from drain plug along with fine metal shavings. Remove old crush washer and install new washer.
5. After diff/trans is drained, reinstall drain plug. 23 - 28 ft-lbs for transmission; 55 - 61 ft-lbs for rear diff.
6. Use 10mm allen wrench to remove fill plug.
7. Remove old crush washer and install new washer onto the fill plug.
NOTE: To fill suction gun, I took off the top, pulled handle out of the gun and poured the oil into it. You could stick the hose into the bottle and suction it out but it wont pick up as much.
8. Using suction gun, fill diff/trans to lower level of fill plug and allow overflow of fluid to drain off.
9. Reinstall fill plug. 23 - 28 ft-lbs for transmission; 55 - 61 ft-lbs for rear diff.
10. Double-check all plugs for correct torque (DO NOT OVERTIGHTEN) and wipe off any excess oil.
11. Lower the car.
NOTE: Since you have the car raised it is a good time to change the engine oil, check your tires for feathering, check your exhaust for leaks and bottoming, check your fuel lines for damage and anything else that may look unusual under your car.
I added a pic of the transmission because it almost the same procedure.
Tools Used
10mm Allen Wrench
Drain pan
Floor jack
Four jack stands or a lift.
Suction Pump/Gun. I bought mine from Advanced Auto for $10.
Harbor Freight has one for $4.99.
Rags
Replacement oil 75W90 about 2 quarts. About 4 quarts for transmission.
Two replacement crush washers.
Update:
Adding the requirements as stated in the 2003 Service Manual
Transmission API GL-4,Viscosity SAE 75W-85
Differential API GL-5, Viscosity SAE 80W-90
Procedure
1. Make sure wheels are blocked.
2. Raise and support car making sure that it is as level as possible.
NOTE: It is better to drain the fluid when it is warm so it flows easier.
3. Using 10mm allen wrench, loosen drain plug and allow diff to drain.
4. Wipe off excess oil from drain plug along with fine metal shavings. Remove old crush washer and install new washer.
5. After diff/trans is drained, reinstall drain plug. 23 - 28 ft-lbs for transmission; 55 - 61 ft-lbs for rear diff.
6. Use 10mm allen wrench to remove fill plug.
7. Remove old crush washer and install new washer onto the fill plug.
NOTE: To fill suction gun, I took off the top, pulled handle out of the gun and poured the oil into it. You could stick the hose into the bottle and suction it out but it wont pick up as much.
8. Using suction gun, fill diff/trans to lower level of fill plug and allow overflow of fluid to drain off.
9. Reinstall fill plug. 23 - 28 ft-lbs for transmission; 55 - 61 ft-lbs for rear diff.
10. Double-check all plugs for correct torque (DO NOT OVERTIGHTEN) and wipe off any excess oil.
11. Lower the car.
NOTE: Since you have the car raised it is a good time to change the engine oil, check your tires for feathering, check your exhaust for leaks and bottoming, check your fuel lines for damage and anything else that may look unusual under your car.
it know it is a stupid question but i have no idea where the transmission plugs are. is it in the front or back? is it close to the oil filter? where are the differential plugs? where to plug suction gun into? suck out or use it to pump fresh fluid in? i am sorry i am a total noob but like to do this type of job. please help clarify please. thank you very much.