MS3 limited-slip differential type (and synthetic gear lube)

[MazdaSteve3]

Anyone know for sure what type of limited slip is in the Mazdaspeed3? The literature states "Tochigi-Fuji torque-sensing limited-slip front differential", but what exactly is the configuration? I would guess that this is a mechanical torsen type, but I've seen talk about conical rings in other Mazdas.

The reason I ask is that I'm talking to Red Line about recommendations for what gear oil to use, and it makes a big difference whether the limited slip uses clutches or frictional components or not.

Any help is greatly appreciated.

 

[neit_jnf]

It's the same as in the RX-8, check what they use

 

[tsunami]

good question... not sure if it is or isn't the same as the rx8 i would wait for a confirmation before you go all nuts yet...

 

[neit_jnf]

good question... not sure if it is or isn't the same as the rx8 i would wait for a confirmation before you go all nuts yet...

It is the same type used in the RX-8. The only differences are that it is setup for fwd instead of rwd obviously and the gear ratios.

 

[Kansei]

Isn't it the same limited slip that Mazda uses across most of their models (like a really late revision of the MSP LSD)?

 

[RPI-Speed3]

This is the exact same unit used in the RX-8. I use Red Line fluids in my RX-8. The RedLine fluid you want to use in the diff is 75W90. I've used it during the summer for my track time for 3 years and it works beautifully. I use MT-90 for my RX-8 tranny, but not sure if that would work for the MS3. I would have to check

 

[Boother]

You can't compare the RX-8 to the MS3 because the RX-8 is a diff only and does not need the same specs as the MS3 transmission.

That being said, Redline says that the MT-90 will work fine in the MS3.

 

[Captain KRM P5]

Isn't it the same limited slip that Mazda uses across most of their models (like a really late revision of the MSP LSD)?

yes it is

mazda dealers use a 75w90 gear oil when doing transmission fluid changes. chrysler typically adds a "limited slip additive" to thier transmission flushes but i have not see mazda do this on thier LSD equipped vehicles.

 

[Captain KRM P5]

You can't compare the RX-8 to the MS3 because the RX-8 is a diff only and does not need the same specs as the MS3 transmission.

That being said, Redline says that the MT-90 will work fine in the MS3.

well, yes and no, for the rx-8 you would still use the same type of gear lube in the rear end

 

[speed3se-r]

old thread, but no one has answered the original question...what type of lsd does the MS3 have? I'd like to know too....i'd guess mechanical as well...but would like some confirmation. I know in my 91 Sentra SE-R, it had a viscous (fluid) type....

 

[tru-boost]

MT90 is the best bet for the MS3. some of the other brands use a friction modifier, which is not recommended for the ms3 tranny. the addition of friction modifiers will actually be too slippery ans cause premature synchro failure and gear grinding.

 

[Kosh]

Cone type super lsd. Which I am guessing is a clutch type?

 

[neit_jnf]

http://www.worldcarfans.com/2060904.006/2007-mazdaspeed3-in-detail-us

A Super LSD cone-type limited-slip differential also minimizes wheel-spin on the inner wheel during hard cornering for smooth, predictable power delivery. Mazda also fits a similar Super LSD unit to the rotary-powered RX-8 sports car and the high-performance MAZDASPEED6[FONT=Arial, sans-serif] sport sedan. [/FONT]

http://www.sae.org/automag/techawards/2002/page5.htm

The Super LSD (limited-slip differential) from Tochigi Fuji Sangyo KK includes a core clutch developed to work well with the strut suspension found in front-wheel-drive vehicles. The unit also works well in the front axle of four-wheel-drive off-road vehicles. Compared to other torque-sensing LSDs, the Super LSD has a lower torque bias ratio (1.5-2.0), which fits well with front suspension systems. Production costs are lower because of similarities to open differentials, and the device can be lubricated with standard differential fluid or ATF. The system can easily replace open differentials because it uses many of the same components and features identical installation points. The device provides good handling and control as well as a cost reduction.

 

[neit_jnf]

Cone type super lsd. Which I am guessing is a clutch type?

it has both gears and clutch.

 

[Kosh]

it has both gears and clutch.

Excellent! Don't all diffs have gears or are these gears different? I know just a little about lsd's so please enlighten me if anyone has more info

 

[Boother]

it has both gears and clutch.

All diffs have gears. A "gear style" LSD (Torsen, Quaife, helical, etc) use worm gears in a way that can create a locking effect within the diff.

The MS3 super LSD does not use worm gears like this, and is thus not a "gear style" LSD. It is better than a normal clutch style LSD in that it doesn't have stiff springs creating a preload on the clutches all the time. Instead, it uses the normal tendancy for the spider gears in the diff to want to separate under load as the source of clutch pressure.

MS3 Super LSD:
http://www.gkndriveline.com/driveli...nt/passive-tmds/torque-sensing/super-lsd.html

Helical, Torsen, Quaife:
http://www.gkndriveline.com/driveli.../passive-tmds/torque-sensing/helical-lsd.html

 

[MS3Chik]

anyone know what the gear ratio is in the ms3?

 

[Kosh]

Just wanted to add this link.

http://auto.howstuffworks.com/differential.htm

 

[cat9050]

RedLine MT90 is UnReal!!

Just changed fluids today - Redline 5W30 in the engine & MT90 in the Trans. (burnout) I can't believe how smooth that car shifts. One of the most best mods I have made (and certainly the cheapest!) Unbelievable difference, it's just snicket, snicket, snicket thru the gears. Too bad the weather will be turning to crap up here in Michigan soon and my baby will be tucked under the cover until the roads are clean and dry come April.



07 Black Mica: 3500miles, Ray's Wheels, MS3 CAI, CPE TBE, AND Valentine 1.

 

[tru-boost]

i did my mt-90 today... it does feel ooohhh so nice. my car took more fluid than normal though. it should take 2.6 quarts. that is factory spec. and what most people say fills it up. mine took all 3 quarts !! i finally did just barely spill over. i held about 2.9 quarts. i also noticed that the first few miles actually felt more rough. i has some rubbing sounds from the diff when going around corners too. after about 10 minutes that all stopped. it is now quiet and smooth as glass. i love it !