08 Legacy GT 5-speed - Question about mixing fluid

[JoeFromPA]

Hi all,

Ok, so as a result of a previous thread some wise guys convinced me to use AMSOIL 75w110 severe gear in my front trans/diff and rear diff/LSD.

I was wondering if it's possible/wise/potentially beneficial to throw a quart of redline shockproof (i.e. lightweight or heavyweight, I'm not sure) into the trans and/or rear diff mixture. After reading up on it, it seems like shockproof has a unique attribute for softening or absorbing some of the "shock" of gears meshing.

Now I read that it should be used in wet sump or splash type settings. I'm not sure how the internals of my system are setup, but I know the infamous "uncle scotty's cocktail" used by many Subaru owners (and now defamed due to excess wear) included Shockproof. My understanding was that the primary culprit for the excess trans wear was the HypoyC used in that cocktail, and that the shockproof was likely innocent.

Anyway, I'm preparing to purchase 4-5 quarts of AMSOIL fluid. I got myself a little hand pump for fluid transferring and a funnel with a 3/8" ID for filling through the trans tube. I need a T70 torx bit, but then I'll be set

Can anyone comment on this one way or another? Also, would it benefit anyone on here to order through you as the AMSOIL sponsor? I'm located in SE PA near west chester.

Joe

P.s. The whole reason for this post is my effort to make the trans/shifting of this vehicle a more pleasant and "fluid" place to work

 

[simple_gifts]

Quote:

Also, would it benefit anyone on here to order through you as the AMSOIL sponsor?

Yes, Some of the funds help support the site;
PM Gary Allan or Pablo.

 

[Pablo]

I would not mix Redline Shockproof with any of the fluids mentioned. You will end up with a fluid that is worse than either alone.

 

[Solo2driver]

No need for Shockproof, the AMSOIL has some of those properties and benefits already in it.

PS-- Uncle Scotty's Cocktail is more of a band-aide for tranny issues, and doesn't last more than about 10K before more problems surface (yes, I have read all 40+pgs on NASIOC hehe). Also, it may be known to cause other issues as well.

 

[DmanWho]

I use RL's 75w140 Lightweight ShockProof (I think it's the Lightweight & not the Heavyweight) in the diff. mix of my iAWD SX4. Suzuki specs. call for the GL-5 Hypoid 80w90.

I would feel comfortable adding some ShockProof. I used about 1/3rd RL in my mix.

 

[Donald]

Go with the Amsoil. Order through an Amsoil sponsor. If you have concerns after the Amsoil is installed, contact Amsoil tech support, they will help. Don't mix. If an Amsoil lube is spec'ed for your vehicle, it should work fine.

 

[edhackett]

As Pablo said, don't mix these fluids. The Shockproof relies on high levels of a calcium compound to provide protection, the Amsoil on a different additive package. When you mix them you dilute the additives to a point where neither will work as intended. This is a classic case of "additive clash".

Ed

 

[DmanWho]

How many ounces of the ShockProof or Amsoil do you need before it can work?

 

[sprintman]

Don't mix in this case.

 

[DmanWho]

What specific additives "clash?"

 

[edhackett]

In this case, all of them. I don't know what Amsoil uses, but for the sake of argument let's say its a type of sulfur-phosphorus-zinc additive system. If you mix these two oils 50/50 you have dropped the Amsoil additive package from GL-5 to GL-4 or less levels. You have also dropped the calcium additive package to a level where it won't protect as designed. The two additives systems work on totally different principles, so mixing them does not gain you the protection of both. You end up with an oil that likely protects half as well as either used alone.

Ed

 

[bluesubie]

Originally Posted By: Solo2driver
PS-- Uncle Scotty's Cocktail is more of a band-aide for tranny issues, and doesn't last more than about 10K before more problems surface (yes, I have read all 40+pgs on NASIOC hehe). Also, it may be known to cause other issues as well.

Did you see this VOA?
There will be a UOA soon.

-Dennis

 

[TeeDub]

The Amsoil 75w-110 is for truck diffs subject to shock loading and for heavy continous towing. Using it in a passenger car street application is a really stupid idea. All this will do is make the diffs run hotter, reduce performance and degrade cold weather shifting.

The Severe Gear 75w-90 is the right choice here....

 

[Pablo]

Originally Posted By: TeeDub
The Amsoil 75w-110 is for truck diffs subject to shock loading and for heavy continous towing. Using it in a passenger car street application is a really stupid idea. All this will do is make the diffs run hotter, reduce performance and degrade cold weather shifting.

The Severe Gear 75w-90 is the right choice here....


Actually the temp difference will be tiny. The 90 is very loud in some Subies and indeed the 110 works much better.

Quote:
Amsoil 75w-110 is for truck diffs...

OK whatever - it's just the old upper viscosity portion of SAE J306 for SAE 90. XW-110 is perfectly fine in cars requiring XW-90!! Especially since car companies and most oil suppliers are even recognizing the new J306. People respect you, don't scare them with Bee Ess.

 

[webfors]

Joe, what did you finally decide on?? What was the result, and are you still happy? Please do tell

 

[SubLGT]

Originally Posted By: webfors
Joe, what did you finally decide on?? What was the result, and are you still happy? Please do tell

He went with 75W110

http://www.legacygt.com/forums/showthread.php?t=98182