fafaforza

iTrader: (3)

Hey folks, I have a 2015 GSR with 21k miles, getting ready to order my transfer, transmission and diff fluids, and going through the manual.

I noticed that the manual lists various fluids with similar labels, but just different enough to make me wonder if they're actually different. People also use different terms loosely so I wanna make sure I get the right stuff.

For example:

For "manual transaxle oil", the service manual lists - Mitsubishi genuine Dia-Queen New MultiGear Oil SAE 75W-80 API GL-3
For "rear axle (differential part)", it lists - MITSUBISHI Genuine DIA QUEEN Multi gear oil LS

Is that the same thing? Is "Red Line 75W-90 GL-5" the aftermarket option here?

Then for "Transfer Case oil", it lists - Mitsubishi genuine Dia-Queen LSD Gear Oil.

Is that yet another DiaQueen fluid? Or same as above? Cause I've only ever seen one DiaQueen product. So would Red Line take care of all three above?

For "rear axle oil (torque transfer part)", it lists DIAMOND ATF-SP III.

What is the preferred aftermarket option for this, if any?

As far as all the different fluids to change, I see:
* manual transaxle oil
* Transfer Case oil
* rear axle oil (differential part)
* rear axle oil (torque transfer part)

Is that the complete list?

I also see a more generic "rear axle oil, with Limited Slip Diff" service, Does that just refer to the above two rear axle parts?

Sorry if this is a RTFM post but I've read through a lot of posts about this and it just left me more confused.

3gturbo

iTrader: (4)

The spf III is for the acd system it only goes into the resivoir the rear diff takes the same fluid as the tcase I use mt90 in the trans lsd 90 mitsubishi fluid for tcase and rear diff.

LetsGetThisDone

iTrader: (1)

Wrong. The rear diff in the X is an AYC unit, and the clutch packs for the AYC sit in a fluid bath of ATF that is separate from the gear oil for the ring and pinion, which must be changed. This fluid is also separate from the fluid in the reservoir in the trunk which goes through the ACD/AYC pump and is used to control the clutch packs.

OP, redline MT90 is what works best in the trans, and redline 75w140 or 80w140 should be used in the rear diff and the tcase for better anti-wear characteristics over a 75w90. And most Universal synthetic ATF's carry approval for use in application requiring the SPIII atf. Just read the back of the bottle to be sure.

fafaforza

iTrader: (3)

The service manual does say that ATF-SP III goes into the torque transfer mechanism of the rear axle. This is the usual drain/fill operation under the car.

It also goes into the reservoir, which is listed as RESERVE TANK FLUID (FOR ACTIVE CENTER DIFFERENTIAL AND ACTIVE YAW CONTROL SYSTEM). I'll use the same in both places then.

@letsgetthisdone - Isn't MT90 too thick? This was the stuff people would mix with MTL for the "cocktail", no? So RedLine came up with MT85. I only grandma-street drive so would 85 be a safer bet?

And I've only really seen reference to RedLine 75W-90. 140 seems heavy. My X is all stock except for an AEM intake.

LetsGetThisDone

iTrader: (1)

MT90 is not too thick, conversely OEM GL3 fluid is too thin and has no business being in a gearbox.

75w90 is thinner than straight 90wt like diaqueen. 75w140 or 80w140 is preferred for that reason. Or stick to the OEM 90wt in the tcase and rear diff.

Not really such a thing as too thick for a differential. Everything is splash oiled or submerged. My tcase runs Amsoil 190wt.

DeweyD

DeweyD