Diaqueen (now MZ320345) SAE90 LSD Oil Discussion

[dparm]

I'm not sure I see any reason for a straight-90 unless you are pushing some insane horsepower and temperatures through there, but I will always defer to the OEM/differential manufacturer when in doubt.

Per the above recommendations, there are a lot of 75w140s to choose from:

Castrol Syntrax Limited Slip
Gulf Competition LS
Millers CRX LS NT
Millers CRX NT
Motul Gear Competition LS
Gulf Syngear
Fuchs Titan Sintopoid LS
Renewable Lube
Red Line
Amsoil Severe Gear
Motul Hypo Synt LS
Motul Nismo Competition Oil 2189E
Liqui-Moly Vollsynthetisches Hypoid-Getriebeöl
Royal Purple Max Gear
Torco SGO
Willall WR35DF
Mobil 1 Synthetic Gear Lubricant LS


FWIW, my M3 specs 75w140 in the rear diff (which has a GKN Visco-Lok LSD). Factory fill is the Castrol I listed up top.

Have you ever considered something from Renewable Lube? Their 75w140 is very affordable and is using very stout basestocks.

 

[kyoo]

thanks for the input - I haven't, but I'm starting a relationship with Red Line so I will probably stick to their fluids

 

[zeng]

Originally Posted By: dparm
Originally Posted By: kyoo
you're pretty focused on the 40c temps - is there a reason that is more important than the 100c temps?

I'm inclined to agree -- why are we focusing so much on KV @ 40 C? It's only one piece of the puzzle here. Unless you have a sensor back there and know the oil is typically operating right at 40 C, that value is of very limited use.
You need to look at it as a whole, not just one number on a spec sheet.



This .........

http://www.bobistheoilguy.com/forums/ubb...our#Post4000376

85W140 ..... typically KV@40*C of 372 cSt;

75W90 ....... typically KV@40*C of 104 cSt.

 

[dparm]

I'm still not clear on what the recommended viscosity for this differential is. Does Mitsubishi use a straight-90? Is OP putting out a ton of horsepower and needs the protection of a 75w140?

The only reason I mentioned 75w140 is that everyone else seemed so set on it. If Mitsu is calling for 90, then I'd use a decent 75w90 unless the car is making 900hp or something (in which case I suspect the rear diff has been swapped).

 

[kyoo]

Mitsubishi uses a straight sae90, and there have been multiple noted failures when people deviate from this fluid, for whatever reason. drivetrain builders as well like the sae90.

for me, I just don't understand why that's the case. I'm maybe 40hp over stock levels, mainly using the car for autox and some road racing. nothing extreme, no hardcore levels of power being pushed through - so I don't understand why 75w90 couldn't do what Mitsubishi's diaqueen sae90 fluid does, if not do it better?

still, especially on the evo forums, people are adamant that their drivetrains fail when going off the diaqueen sae90.

my aftermarket diff is a cusco, but the r&p is still Mitsubishi.

my drivetrain builder did recommend using 75w140 but he's used to people making 500hp+

 

[dparm]

Is the diff failure stuff anecdotal? Do people even have all of the facts? I'm sure there is a lot of CYA happening there. No one is going to openly admit to abusing the car (if they have more than two brain cells), so they'll just find a scapegoat like the fluid.

Not saying that straight-90 is incorrect, but a very vocal minority of people might just be blowing it out of proportion.

 

[kyoo]

here are a few websites - it's not so much the diff as it is the transfer case:

http://www.jackstransmissions.com/pages/oil

http://www.teamrip.com/transfer_case_hypoid_gear_oil_recommendation_info.html

http://www.coordsport.com/blog/2010/05/evo-gear-lsd-oil-recommendations/ (special note)

http://www.maperformance.com/products/mitsubishi-diaqueen-gl5-lsd-gear-oil-quart-mit-mz320345

I'm not saying I can't use the Diaqueen - I just don't understand (and I think any regular BITOG'ers as well) what makes Diaqueen so special?

I just sent out samples of diaqueen and severe gear 75w90 to blackstone to see at least what the exact viscosities and additives are..

 

[dparm]

Yes, a VOA of the OEM fluid would be interesting.

Any idea what fluid it really is? IIRC, the Mitsu dual-clutch fluid is relabeled Castrol BOT 341 (aka Castrol Syntrax Dual). Maybe the straight-90 diff oil is just Castrol Axle Limited Slip 90?

http://www.castrol.com/en_nz/new-zealand/products/cars/axle-universal-oils/axle-limited-slip-90.html

KV @ 40C = 175
KV @ 100C = 17.80
VI = 95
Pour point = -21 C
API GL5
MIL-PRF-2105F, MIL-L-2105B/C/D/E
Mack GO-J

 

[zeng]

Thanks for sharing the links.

http://www.teamrip.com/transfer_case_hypoid_gear_oil_recommendation_info.html

Your application requires GL5 80W140 >> 75W140 >> Straight SAE90 as recommended above.

A mineral 85W140 would do as well.

Evidence aplenty that a 75W90 simply won't cut it ........ due to too low a KV@40*C ..... never

mind it's super duper base stocks AND additives package !

 

[kyoo]

should have the oil analyses back in a couple weeks.

zeng, i think you are the only one pushing that viscosity being high at 40c is a good thing... can you explain?

obviously this isn't 40c but:

https://www.youtube.com/watch?v=S3lrzV1MCtU

as i understand it, the lower the viscosity at colder temps, the better. not sure why you are pushing that it is a good thing? thats why we run 0w30, 5w30, 10w30 in our motors. are you running straight 30 in yours?

 

[zeng]

I'd already demonstrated above ..... favorable higher operating viscosity from oils of higher KV@40*C..... typically in differentials ... never mind the temperature difference ...

" This .........
http://www.bobistheoilguy.com/forums/ubb...our#Post4000376
85W140 ..... typically KV@40*C of 372 cSt;
75W90 ....... typically KV@40*C of 104 cSt."

The youtube is a poor comparison at temperature regimes of -40*C, between 75Wxx and 80Wxx .......
Besides ,it's irrelevant to my discussion on KV@40*C ....... and it's erroneous and misleading ..... if you know what I mean.

 

[kyoo]

it's not favorable if it's got higher viscosity.. it's favorable if it has lower, until it reaches operating temp...

 

[MolaKule]

Originally Posted By: kyoo
it's not favorable if it's got higher viscosity.. it's favorable if it has lower, until it reaches operating temp...

I don't understand his 40C viscosity posts either.

Maybe he can explain what he is trying to say.

 

[kyoo]

long awaited results of the oil analysis! interestingly, diaqueen has higher contents of boron and phosphorous. the viscosity at 100c is a little thicker - but i put in a special request - test it at 140c (284F), an "overheating" situation. the severe gear is a little thicker, meaning it's more stable and provides more protection at hotter temps, though at that point you may be in some trouble anyway.

Amsoil 75w90 severe gear:

Diaqueen:

thoughts?? i didn't get the cold temp, but so far zeng is still the only guy who thinks thicker at cold temp is better

 

[zeng]

Requote dated 02/05/16 ....

Originally Posted By: zeng
Originally Posted By: kyoo
Is there something special about this fluid? I've never been able to find any specs on it, other than it is SAE90 & GL5. However, it seems all SAE90 fluids run in the 13-24 range at 100c, and 600-700 at 40c.

This fluid is nothing special ..... the difference is in KV@40*C/KV@100*C.



Edit:Should I be more specific ......... In relation to a typical 75W90 ,Diaqueen should have a much higher KV@40*C in particular, and 'possibly' higher/similar/lower KV@100*C which is of lesser relevance in differentials generally.

 

[kyoo]

right, in that the viscosity at 40c is worse for the sae90 -- you're still the only one that thinks the higher viscosity at cold is better, several people have brought it up now

 

[zeng]

Ooops .... edited prior ...

 

[kyoo]

Too bad I can't update the original post.. here are the results from the four gear oils I've tested:

Originally Posted By: kyoo
All results:

 

[kyoo]

just to reiterate - looks like they all use some mix of boron and phosphorus - diaqueen uses even more than amsoil, and redline more phosphorus than both combined.

shockproof is obviously very different, and though I ran it briefly in my t-case, will be swapping it out for 75w90. will probably take several flushes to get out.

 

[kyoo]

Originally Posted By: zeng
I'd already demonstrated above ..... favorable higher operating viscosity from oils of higher KV@40*C..... typically in differentials ... never mind the temperature difference ...

" This .........
http://www.bobistheoilguy.com/forums/ubb...our#Post4000376
85W140 ..... typically KV@40*C of 372 cSt;
75W90 ....... typically KV@40*C of 104 cSt."

The youtube is a poor comparison at temperature regimes of -40*C, between 75Wxx and 80Wxx .......
Besides ,it's irrelevant to my discussion on KV@40*C ....... and it's erroneous and misleading ..... if you know what I mean.


yea, you're still the only one i've seen here who thinks thicker oil at cold temps are BETTER for differentials.