[Majin]

so...

the best diff oil for the STi is...?

let's start a "the product i use is better than anything out there because" thread in here...

[solbergfan]

Originally Posted by Majin

so...

the best diff oil for the STi is...?

The PROPER diff oil.

[Majin]

nice!

[DustynF]

I think its like telling someone "ahh just get the regular stuff" and then everybody else wants to get the best because they seen some cool comercial about it on the speed channel. I bought Motul 90 pa from motorspot.com. Transaction was flawless.

[StiManny]

redline ftw..

[Singletrack]

Originally Posted by Arcticsun

Just a quick FYI. These "plugs" referenced here for torque specs is incorrect, there should only be ONE plug with that spec and its the 1/2" drive one (drain).

32.6 breaks the temp sensor plug. I dont know if this is common knowledge in this thread, but i certainly feel like an idiot now :/

Just going back through some old threads and I saw this post. I wanted to double check that "I" didn't screw up. What I can tell you is that this is, in fact, what the 04 factory service manual states:

"5) Install the filler plug or rear differential oil temperature switch onto rear differential gear case firmly.

NOTE:
Apply fluid packing to the filler plug or rear differential oil temperature switch threads.

Fluid packing:
Three Bond 1105 (Part No. 004403010)

Tightening torque:
49.0 N·m (5.0 kgf-m, 36.2 ft-lb)"

If also states 49Nm on the other bolt (1/2") earlier in the same section:

"3) Install the drain plug after draining oil.

NOTE:
Apply fluid packing to the drain plug threads.

Fluid packing:
Three Bond 1105 (Part No. 004403010)

Tightening torque:
49.0 N·m (5.0 kgf-m, 36.2 ft-lb)"

I did not torque the top bolt with a torque wrench, only the bottom one. However, I know what 30-40 ft-lbs of torque feels like given a specific length breaker and that is more or less what I applied.

If other people are having issues, then please speak up. Does anyone have the 05 or 06 manuals? Same spec or different? Seems odd to me that this would be wrong because the bolts are the same diameter, thread pitch, thread count etc - IIRC.

Also, to the people that this happened to - how exactly did the bolt fail? Any chance it was cross threaded in there?

EDIT - It just occured to me that using too much liquid gasket could definitely affect the torque wrench. I would only put liquid gasket on half the threads or so. Leave at least the first few threads going into the diff free of liquid.

[awd4life]

****old thread revival****

so trying to figure out what was making my rear diff chirp/chatter a little lately i firured i would do some searching on the subject and found this thread. and to add to the products w/ the proper type of additives to work in an STi diff. i found a product called Sta-Lube 80w-90 limited slip gear oil. it's made by CRC industries who supplies a bunch of the oils and chemicals that i use at my work (deisel truck repair shop) the top few ingredients are paraffinic, petroleum, and mineral oil.

i was previously running some Redline shock proof heavy weight in the rear diff and got chatter after about two months so i'll try this out and let every one know if it works to my sensitive ears liking. not as bling as OEM or Motul but far more availible to my self being that we stock it.

[STInk]

Lately I've been feeling like my car has lost traction; like maybe my tires have hardened up or worn out. Twice in the last month I spooked myself in the rain, giving it a little extra gas to "see what it would do" around a corner and the rear swung around faster than I expected. Two days ago I noticed some horrible diff binding while navigating a parking garage; even worse with the diff lock on. Then I found this thread.

Last night I drained out my Motul and replaced it with Subaru Factory fluid and the car is back the way I remember. Much better traction, no noise. God knows how much damage I did to my diff. They are $1600, btw.

[WolfPlayer]

Originally Posted by STInk

Two days ago I noticed some horrible diff binding while navigating a parking garage; even worse with the diff lock on.

If you put the diff lock on then you always hear horrible binding noises when turning on pavement. That is completely normal. Now, if you DO NOT hear horrible binding noises with the diff lock on (dry pavement) then you have a problem.

t

[ThePigSTi]

Do yourself a favor and heat this stuff up before you try to pump it in. It is no less thick than honey at room temp and I broke the pump trying to get it in the first time.

[005sti]

just talked to the parts and service guys at the dealership when i picked up my diff fluid, they were out of the gasket sealer for the rear diff and they said that they often don't use it, they just torque it down and that it works fine. they did my rear diff last time and i have had no leaks. any thoughts, experiences?

[Mykl]

Originally Posted by solbergfan

The PROPER diff oil.

And that is???

Really, we've got a basic clutch type limited slip differential, right? So any oil designed for use with a clutch type limited slip should work.

I ordered some from a dealership and they sent me Penzoil 80w-90. This is from a dealership that does a lot of performance work that I have respect for, so I'm going to throw it in and assume it will work.

[005sti]

the stuff i got from the dealership is fuji heavy industries LSD oil, specific for our mechanical lsd in the rear diff. however, don't be surprised if the dealership sent u the wrong stuff because they were going to put in generic partsmaster crap tranny oil in before i bought my own valvoline full synthetic when they changed my tranny fluid a few mos ago.

[Supraru]

yeah Red Line has a "power pack" specific for the sti, including diff and tranny fluid (different of course). You can vary the diff lock up characteristics with friction additives. so FWIW, Red Line would be a fine choice for 6MT and R180, among others. no one can say you cant get redline and you have to get the re-labled Subaru stuff.

[Mykl]

There's nothing special about our rear differential. It's just a basic clutch type limited slip type diff. There's really no reason why any standard LSD gear oil won't work as long as it's in the recommended viscosity range. However, if it can be shown that our differentials malfunction when non Fuji Heavy Industries oil is used, I will take back my statement and use that instead.

The transmission is the part of the car that's incredibly picky about what oil you run. I choose to run Extra-S, because I *know* it works.