Differential oils ?

[Exhaustgases]

It seems no one stocks straight 90, how come? Is 75W-90 and 80W-90 supposed to be a good substitute?
I say it is not very different at all, because at low temps it will lube like normal 90 would at operating temp, and the same as well at op temp for the multi vis.

 

[Chris142]

Same as multi weight engine oils. 50 yrs ago 30wt and 90wt were the norm. Now it's 5w20 and 75w90.

 

[simple_gifts]

Can't find the video, but someone posted a cold temp video in which a 80w-90 was actually channelled by the spinning gears; One revolution to pick up the goopy oil and then no lube at all since the rest of the bath was basically not too fluid.

No sense trying to escape the benefits of multiviscosity oil.

 

[mjoekingz28]

You talking about the Lucas wheels?

 

[userfriendly]

Exhaust; Take a look in Technology and white papers. MolaKule bumped up "gear tribology" in 2 parts. Read those threads, maybe your questions are answered there.

 

[simple_gifts]

Originally Posted By: mjoekingz28
You talking about the Lucas wheels?


No.

 

[dailydriver]

IF you MUST HAVE a straight 90 weight GL-4/5, Motul does make one, their mineral based 90 PA fluid.

 

[meborder]

Not sure of your application, but the only reason i can think of to use straight 90wt is for old equipment which calls for GL1 rated oil. Most likely because the gearbox contains yellow metal.

If that's the case, the only GL1 rated oil I could find was straight 90wt.

I got mine at NAPA.

If you can use GL4 or 5, then just use the current 75w90. No reason not to.

Jmho.

 

[zeng]

Originally Posted By: Exhaustgases
It seems no one stocks straight 90, how come? Is 75W-90 and 80W-90 supposed to be a good substitute?
I say it is not very different at all, because at low temps it will lube like normal 90 would at operating temp, and the same as well at op temp for the multi vis.


Motul TRANS MB 85W-90 GL5 is suitable as replacement.

It's KV@40C of 187 cSt offers better margin of wear protection than most contemporary 80W90.

Btw 80W90 of typical KV@40C offers better protection against a 75W90 of typical KV@40C.

JMO.

 

[zeng]

Originally Posted By: dailydriver
IF you MUST HAVE a straight 90 weight GL-4/5, Motul does make one, their mineral based 90 PA fluid.


The 90 PA is disignated SAE 90.

However, it's KV@40C is 140 CSt.

IMHO , Motul TRANS MB 85W-90 of KV@40C at 187 cSt offers far superior wear protection over 90 PA.

 

[Shannow]

Originally Posted By: mjoekingz28
You talking about the Lucas wheels?


Pretty sure that it's this one...

 

[Shannow]

Here's an Amsoil test where not only do they get some interesting results, they apply the 4 ball correctly.

http://www.lastgreatroadtrip.com/wp-content/uploads/2010/11/gear-oil-comparison.pdf

 

[zeng]

Originally Posted By: Shannow
Here's an Amsoil test where not only do they get some interesting results, they apply the 4 ball correctly.

http://www.lastgreatroadtrip.com/wp-content/uploads/2010/11/gear-oil-comparison.pdf



Saw Amsoil 75W140 UOA in BitoG where it's KV@100C shears more than 1/3. Scary ........

 

[Y_K]

"independent" lab was their lab.. there were a few squeeks here alleging it was done at SWRI.. I called SWRI after that and heard a chuckle with 'no comment'. good luck with that "test"

 

[CarbonSteel]

Originally Posted By: zeng
Saw Amsoil 75W140 UOA in BitoG where it's KV@100C shears more than 1/3. Scary ........

After 80K with at least 35K of that towing in my 2010 FX4, the CSt Visc.@100°C was 24.31 and the VOA was 26.35; only about a 10% change--obviously each axle is different.

 

[Shannow]

Originally Posted By: Y_K
"independent" lab was their lab.. there were a few squeeks here alleging it was done at SWRI.. I called SWRI after that and heard a chuckle with 'no comment'. good luck with that "test"


Amsoil owns SWRI ?

 

[Hootbro]

Originally Posted By: Shannow
Originally Posted By: Y_K
"independent" lab was their lab.. there were a few squeeks here alleging it was done at SWRI.. I called SWRI after that and heard a chuckle with 'no comment'. good luck with that "test"


Amsoil owns SWRI ?


No, they do not. Southwest Research Institute is an independent research and test operation that does a multitude of different testing for corporations and companies under contract. They will test to any method or specification that a company contracts them to. So if they are given garbage or biased specs to test to, then garbage in and garbage out.

Also, Southwest does not comment regardless who they may or may mot be testing for.

 

[Y_K]

Originally Posted By: Shannow
Amsoil owns SWRI ?


No, they cannot afford. SWRI is a seriously expensive proposition.

 

[zeng]

Originally Posted By: 2015_PSD
Originally Posted By: zeng
Saw Amsoil 75W140 UOA in BitoG where it's KV@100C shears more than 1/3. Scary ........

After 80K with at least 35K of that towing in my 2010 FX4, the CSt Visc.@100°C was 24.31 and the VOA was 26.35; only about a 10% change--obviously each axle is different.



I stand corrected.

Nice shear stability you have there in Amsoil, despite the high torque duty cycle.

 

[artificialist]

Toyota called for SAE90 in most of their trucks. Wherever I worked, we just used 80w90 conventional or 75w90 syn and never had a single problem.

I used conventional 80w90 in my car, then switched to syn 75w90. I only have 45,000 miles on my car, so I can't say if it helped or harmed my car.