Tranny, Rear Diff and T-case Fluids

[dambikeracer]

Tranny- I have been running the stock DiaQueen 75-85w from day one. Planning on switching to Amsoil MGT 75-90 with my next change.

Rear Diff- I have been with the OEM DiaQueen 90w LSD Fluid. I was thinking of changing to the Amsoil SEVERE GEAR Synthetic Extreme Pressure (EP) Lubricant 75W-90 SVG.

T-case- Same as the rear diff, OEM DiaQueen 90w LSD and have no plans on changing that, just adding slip lock.

Now that I am up to 476WHP, I want the best fluids in my car for drag racing and daily driving. What is my best bet for lubricants?

[dambikeracer]

After doing some research, I think that I am going to run Amsoil MGT in the tranny and Redline Shockproof Heavy in the transfer case and rear diff. Any thoughts on that?

Also anyone ran both the Amsoil MGT and the BG Syncro Shift II? If so, which one did you like better and why?

[apagan01]

You are making some great choices of oils for your tranny, even if you dcided to go with AMSOIL for the TC and rear diff it would be perfectly fine for DD and racing, plus the SVG is a cleaner oil and longer lasting by being sythetic, unlike OEM.

[Liquid Gold]

Not a big lover of Redline Heavy Shockproof...

It uses Polymers for Viscosity Improvers that centrifuge out and have been found to look like little soft globs in the nooks and crannies. If they centrifuge out, what good are they ?

Stay with Diaqueen or switch to AMSOIL SVG 75W-90. I know of several race teams running the AMSOIL and have been for the last couple years with no problems.

LG

[JKD]

Originally Posted by Liquid Gold

Not a big lover of Redline Heavy Shockproof...

It uses Polymers for Viscosity Improvers that centrifuge out and have been found to look like little soft globs in the nooks and crannies. If they centrifuge out, what good are they ?

Stay with Diaqueen or switch to AMSOIL SVG 75W-90. I know of several race teams running the AMSOIL and have been for the last couple years with no problems.

LG

Great info here!

[Liquid Gold]

Originally Posted by JKD

Great info here!

Thanks JKD

LG

[dbsears]

I foresee one problem here. Why replace a strait 90wt oil with a multiviscosity 75w90 oil? Is there any added benefits\drawbacks to this? Obviously still a 90wt oil but its a tad different than going from say a 5w-30 to an 0w-30 engine oil. Stock diaqueen is mineral based non synthetic oil but what drawbacks does that have in a differential/transfercase situation? I run MTG in my tranny but have always ran stock diaqueen in my diffs/tc as I have never seen any positive data showing why not too.

[Liquid Gold]

A multi viscosity oil, fluid or gear lube, that is a Multi Grade, will lubricate better at cold temps.

Looking at petroleum products:
A Multi Visc oil such as 5W-30 will only lube to about 225-235 and that is pushing the limits. They also begin to shear (lose viscosity. A Straight weight 30 will lube up to about 275 or so.

So why not use straight weights ? One word, WEAR ! At cold temps, a straight weight will nopt provide adequate lubrication to vital parts. One reason I hate seeing people with the attitude of a thicker oil provides more protection and they run a 20W-50.. They may not have a catostrophic failure immediately (they may) but you have parts such as the cams and Turbo's that are being denied lubrication at a critical time.

People keep that Petroleum guideline, even some good engine builders follow that antiquated thought pattern. Some admittedly just tell their customers "what they want to hear" for oil viscosity. I know, I asked one with a very good rep right here from these forums.

A Premium Synthetic oil, fluid, gear lube (PAO/Ester) will not even get into it's additive packs at 235..

In the case of the 90 wgt Diaq., Mits is going to look at it like... Some People will put the cheapest junk in their car and we have to Spec for that. If they run a better fluid, they are ahead of the game. It also comes down to the "Bean Counters".. People think "Engineers" Have the only say so... That's a laugh... Bean Counters look at it like "How can we cut price within an acceptable margin".. (Allowable warranties)

LG

[dbsears]

While a good response it still begs the question HOW is a multi-viscosity fluid is better than Diaqueen in a differential situation. Besides cold flow properties what else does it provide? Now obviously there are theoretical advantages but I am curious as will they become apparent? We are talking Transfercase and rear diff temps. I know what typical temps they see in an Evo and it's not that high but it does get up in track usage. Diaqueen is also known to be a pretty good fluid...definately not cheap by no means.

Obviously what I trying to get out besides general theoretical responses is actual data. Personally I sell Amsoil on the side and love their fluids but I just have never justified a need to upgrade as I have done quite a bit of research on Diaqueen. Now the only thing that interests me is the Amsoil being full synthetic vs mineral based for the Diaqueen. My understanding though is diff temps don't normally reach past 220-230F. I am curious on some data though...I would love to try some myself if indeed it's worth it.

[apagan01]

Its just normal business in Corporate America or any other place to just give the customer just enough of what they need and not a bit more or less just enough to get by.

However then you have the company that will go out of their ways to provide a better service/product although us consumers will have to pay a little more to use those goods that exceed expectations.

Originally Posted by Liquid Gold

A multi viscosity oil, fluid or gear lube, that is a Multi Grade, will lubricate better at cold temps.

Looking at petroleum products:
A Multi Visc oil such as 5W-30 will only lube to about 225-235 and that is pushing the limits. They also begin to shear (lose viscosity. A Straight weight 30 will lube up to about 275 or so.

So why not use straight weights ? One word, WEAR ! At cold temps, a straight weight will nopt provide adequate lubrication to vital parts. One reason I hate seeing people with the attitude of a thicker oil provides more protection and they run a 20W-50.. They may not have a catostrophic failure immediately (they may) but you have parts such as the cams and Turbo's that are being denied lubrication at a critical time.

People keep that Petroleum guideline, even some good engine builders follow that antiquated thought pattern. Some admittedly just tell their customers "what they want to hear" for oil viscosity. I know, I asked one with a very good rep right here from these forums.

A Premium Synthetic oil, fluid, gear lube (PAO/Ester) will not even get into it's additive packs at 235..

In the case of the 90 wgt Diaq., Mits is going to look at it like... Some People will put the cheapest junk in their car and we have to Spec for that. If they run a better fluid, they are ahead of the game. It also comes down to the "Bean Counters".. People think "Engineers" Have the only say so... That's a laugh... Bean Counters look at it like "How can we cut price within an acceptable margin".. (Allowable warranties)

LG

[dbsears]

Then how about you give us what we need...proof and definitive evidence. There should be some compelling data around...problem is 99% of time nobody bothers to post it.

[tim85851]

my friend just became an amsoil dealer and i need to do my 60k drivetrain fluids change...is anything going to happen if i dont use diaqueen in my tcase and rear diff?

i looked on amsoil's website and it says to use:

transmission (3 quarts of Manual Transmission & Transaxle Gear Lube 75W-90 MTGQT-EA)

transfercase (1 quart of Severe Gear 75W90 SVGQT-EA)

rear differential (1 quart of Severe Gear 75W90 SVGQT-EA)

i read around and everyone changes their tranny fluid but when it comes to tcase and rear diff people are going both ways...either staying with diaqueen or changing to synthetic...

WHAT SHOULD I DO?!?!

[dambikeracer]

Change to Amsoil... I will be changing to the Manual Transmission & Transaxle Gear Lube 75W-90 in my tranny fluid for the first time. In the past I have ran nothing other then OEM DiaQueen. As for the t-case and rear diff, I'm going to go with the Redline Shockproof Heavy because it is heavier then the Amsoil Severe Gear 75W90. As I drive my car less and less as a DD, and more as a drag racer, I want more protection!

[Liquid Gold]

Originally Posted by dbsears

Then how about you give us what we need...proof and definitive evidence. There should be some compelling data around...problem is 99% of time nobody bothers to post it.

There have been tests performed on different Gear Lubes. Diaqueen isn't one (at least by that name) as it isn't worth spending the money on a small market share item. There is one gear lube test that runs around $15,000..

Find out who makes Diaqueen this year, and it maybe in those tests..

I found this .. http://bestoil4you.com/files/g2457GearLube.pdf

LG

[Meevo]

Are you guys going to run some LSD additive in your rear diffs as well as either redline or amsoil?