Hey everyone.

FYI: Jiffy Lube will change your diff or tranny fuild for $29...just bring them the oil. I did this over the weekend.

Just an FYI, for those that dont wanna get dirty, crawl under the car, and dispose of the oil safely. 10 mins at Jiffy Lube and I was done. The guys were sooooo cool. They were so drooling over my car, they didnt even charge me!! I gave the guy a $20 tip for his effort.

 

I take those guy a 12 pack, and they will do it for free.

I'll probably change my gear oils this weekend as well. Yay!

So three quarts is enough for the trans and the diff housing?

 

For the MT, it's:
US measure: 3-1/4 qt
lmp measure: 2-3/4 qt (don't know what this is...)
or 2.9liters
API GL-4
Viscosity SAE 75W-85

 

yeah, 3qt for the tranny....and about 2qt for the diff If you buy 5 wt, you'll have more than enough to do both.

 

Hey guys,

I decided that I want to swap out the tranny and diff fluid in my Z also. I understand the drain and fill procedure now (thanks to this post) but I am confused as to what kind/viscosity/brand of fluid to be used in the tranny and the differential. I assume the tranny uses a completely different kind of fluid than the diff, is this correct? If you have done this fluid swap before can you post what fluid you used for the tranny? What fluid for the differential (I have an enthusiast with stock lsd)? Have you run into any problems that I should look out for?

Thanks so much!

 

I'm running Redline MT-90 in the tranny and Redline 75W-90 in the diff. IIRC, MT-90 is similar in viscosity as 75W-90, but one of them (I think MT-90) has friction modifiers.

2k miles and a few track weekends so far and nada problems.

Michael.

 

Thanks for the reply! Im going to buy the Redline fluids you suggested, did you use 3 quarts for the tranny and 2 for that differential?

 

The FSM lists manual tranny fluid capacity at 3 1/4qt and diff fluid capacity at 3pt (1 1/2qt).

I'd buy 4qts of tranny fluid (i.e. MT-90) and 2qts of diff fluid (i.e. 75W-90).

For me, I ran out of tranny fluid and ended up using about 1/8qt diff fluid.

BTW, diff fluid stinks worst than a skunk. Be careful when draining and filling or else you'll smell like *** for a month.

Michael.

 

Just an FYI:

For those of you w/ clutch type diffs (ie. Nismo, KAAZ, Cusco) DO NOT use redline/mobil/royal purple synthetic fluids! It will not soak into the discs properly and you will destroy the LSD.

I run the KAAZ oil only (additives already inside) but any good quality non-synthetic oil will do.. and try to change after every event or 3,000 street miles.

The drain and fill plugs are 10mm hex (3/8 might strip the bolt).

I change the aluminum crush washer every other time on the plugs. Never had a leak.

Easiest way to fill the diff is using a small pump w/ two long hoses which can be bought at any autoparts... just pump until it starts to come out of the filler.

It is also easier to fill the diff on the car, even if you have the pumpkin out, because you will spill some of the fresh oil when re-installing the pumpkin out of the front or side seals when re-installing. HTH

 

So it's safe for the stock lsd?

I run the KAAZ oil only (additives already inside) but any good quality non-synthetic oil will do.. and try to change after every event or 3,000 street miles.

The drain and fill plugs are 10mm hex (3/8 might strip the bolt).

I change the aluminum crush washer every other time on the plugs. Never had a leak.

Easiest way to fill the diff is using a small pump w/ two long hoses which can be bought at any autoparts... just pump until it starts to come out of the filler.

Quote:

It is also easier to fill the diff on the car, even if you have the pumpkin out, because you will spill some of the fresh oil when re-installing the pumpkin out of the front or side seals when re-installing. HTH

Whats the pumpkin? o.o

 

Sorry, the "pumpkin" is another name for the differential housing (because of the shape).

 

Anyone know what brand of differential fluid is compatible with OE LSD on my Track? Is Limited Slip additive needed? How important is it to stick with 80W-90 or SAE 90 (as recommended in the service manual?)

 

no additive needed according to the service manual, but ask the oil manufacturer to be sure

and the clutch type diffs most certainly CAN take synthetic...at least the Cusco and NISMO ones can

 

anybody use gm synchromesh friction modfied in the tranny? I know it works wonders in honda transmissions but i don't know about nissans.. Anybody know the weight of the gm synchromesh since the VQs require 75w90?

 

You "do not" want to add friction modifiers or a gear oil that contains friction modifiers to the 6MT. They are too slippery at lower temps to allow the synchros to operate properly.

The manual calls calls for GL-4 (no modifiers) in the 6MT and GL-5 in the diff (can have modifiers). Also some modifiers contain sulpher compounds which are not "synchro safe".

FYI , Check out the "redline oil" website , good info there.

 

Just checked Redline's website. Their 75W-90 differential fluid comes with friction modifiers already added. But in the product data .pdf file, it mentions that more modifiers can be added based on application. Do I need to add additional friction modifierss(over what is already in Redline 75W-90) for stock LSD?

 

Well, after reading this thread I flushed out my fluids today. I used 5qt. mobil 1 5w30 for the engine, the tranny got Redline 2qt. MTL + 2qt. MT-90 mixed, and Royal Purple 75w90 gear oil for the diff.

The only difference I noticed was that the rear end of the car slides around a little bit more than usual. The tranny feels the same.

All in all, I spent ~$90 on the fluids and oil filter, and about $60 to have Jiffy Lube do the labor. I hope all of this money and time was worth it.

 

As far as Redline oil to use in the 6MT, Either
a 50/50 mix of MTL/MT90 or straight MT90.

If you live in a warm climate and intend to track the car, Straight MT90 seems a better choice. If you live in a cold climate and/or rarely track the car the mix may be better. Note neither MTL or MT90 contain friction modifiers , and hence will make your synchros more cooperative.

Something to note from my experience. I used RP 75w90 in my 6mt for about 5k miles. For summer and track use it worked like a champ and smoothed things out noticeably. Now the rub was that soon as temps dropped below ~45F here in Cali, I noted that until warmed up my second gear synchro was a little stubborn , epsecially upon matched downshifts from 3rd. So I changed out the RP with Redline MT90.

Well now the 2nd gear syncro is much more cooperative in cold weather. So my assessment is that the RP is "too slippery" for good full temp syncro operation. RP is ; however, a very good choice for open diffs and clutch type diffs, I woull not recommend the RP 75W90 for use in the Viscous LSD since it will minimze the LSD's effectivenss (specifically in the OEM Viscous LSD).

 

So many differnt answers So from what I gather

Tranny oil MT-90 Redline 3 1/4 QT

Differential 75w-90 1 1/2 QT

Stock LSD do not use Non slip...Use gear oil.

With all the diffent answers I tried to combine the majority.

Thanks guys

 

What a messssssssssssss