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>>Tranny Fluid Info and Experimenting Thread<< (Amsoil, Redline, USC, etc.)

207K views 404 replies 74 participants last post by  persia 
#1 · (Edited by Moderator)
>>Tranny Fluid Info and Experimenting Thread<< (Amsoil, Redline, USC, etc.)

UPDATE:

To start off, a link to " MEMBER TESTIMONIALS (on page 2 of this thread)" where there are tons of testimonials and lots to read.

What I ended up running and install pics. >>>>HERE on page 4<<<<


MY Blackstone analysis of my USC fluid that I replaced. >>>HERE<<<

Also started a "What fluid was your car running when it blew?" thread.

One more link to the Uncle Scotty's Cocktail Thread on Nasioc.

With that said where I started at 1-30-08:

So it is once again tranny fluid time in my car, or getting close anyways. Last time I used a synthetic version of USC or "Uncle Scottys Cocktail" I came up with. It works great, but in my quest to not leave well enough alone and brand homogeneity, I wanna try an all Amsoil formulation. Specifically, replace the Frankenstein colored Redline Lightweight shockproof with something, but we'll see where the research and findings take me.

What I am currently running:
I mixed up a batch of "Uncle Scottys Cocktail" but a full synthetic version in my 06 TR at 15k miles.

1 qt Redline lightweight shockproof
1 qt Amsoil syncromesh
2 qt Amsoil 75w90 gear oil.
What I am thinking about going with:

4 0z Amsoil slip lock
1
qt Amsoil MTG
1 qt Amsoil syncromesh
1.5 qt Amsoil 75w90 gear oil.

The bold is what I am thinking about to replace the Lightweight shockproof. They have a lower kinematic viscosity at 40 deg which should lead to improved shift at cold temps. Using all Amsoil products also guarantees (through Amsoil) that I can up the service interval considerably.



Discuss.

Here are the results:

Now at page 24 we have come to some conclusions:

* We've decided Uncle Scotty's cocktail shifts nice for a while but breaks down really fast and needs really short change intervals.
--Also don't think syncromesh needs to be in the blend
--There is also concern it may cause extra wear

* Redline Lightweight Shockproof works well in the 5MT but not the STI trans (slinger lubrication versus pump)
--Seems to work just as well straight as mixed

* Straight Severe Gear 75w90 from Amsoil is not good in cold weather, but works well when mixed with shockproof

* SD_GR still loves his Valvoline conventional 75w90

* Subaru Extra S is the greatest gear oil to put in a stock Subaru
--It works well for a long time, shifts great, but is not sold in the quart. Its sold in the 5 gal drum, but many Subi tuners and dealer have it

FWIW Redline 75w90NS is what you'd run in the 5MT, but in non-mixed form it hasn't netted near the result of the Extra-S. Don't use MT90.
 
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#350 ·
So the pin turned out to be debris dropped by the builder. However the tranny was still leaking at the axle seals. Geniuses never replaced those. But it's fixed now.

I'm running 1qt of Motul 300 and the rest shockproof. I also added 2oz of Redline Friction Modifier. It really smooth things out with the clutch type front LSD. Running very smooth and strong now.
 
#351 ·
I picked up a 2008 WRX recently and I'm just shy of 33k miles. I'm gonna be doing my 30k mile maintenance this weekend and am wondering what type of oil I should use. I was gonna go with Redline, I've used this in my motorcycle before and it worked great, never put it in a car though... honestly I never had a car worth putting Redline in. I've been reading about Uncle Scotty's Cocktail, most posts on that seem to be geared to older model WRX's than mine though. And lastly Extra S, I can't find this by the quart here, but my local dealer has this, although the service guy there seemed like he didn't really want to sell me it since I wasn't having the service done at their shop. Any input what brand or mix I should go with?

Jason

P.S. I live in the Denver area by the way.
 
#352 ·
Now at page 24 we have come to some conclusions:

* We've decided Uncle Scotty's cocktail shifts nice for a while but breaks down really fast and needs really short change intervals.
--Also don't think syncromesh needs to be in the blend
--There is also concern it may cause extra wear

* Redline Lightweight Shockproof works well in the 5MT but not the STI trans (slinger lubrication versus pump)
--Seems to work just as well straight as mixed

* Straight Severe Gear 75w90 from Amsoil is not good in cold weather, but works well when mixed with shockproof

* SD_GR still loves his Valvoline conventional 75w90

* Subaru Extra S is the greatest gear oil to put in a stock Subaru
--It works well for a long time, shifts great, but is not sold in the quart. Its sold in the 5 gal drum, but many Subi tuners and dealer have it

FWIW Redline 75w90NS is what you'd run in the 5MT, but in non-mixed form it hasn't netted near the result of the Extra-S. Don't use MT90.
 
#357 ·
The rear diffs aren't partial really unless you have an sti, so any (even conventional) GL5 75w90 is fine. I used Extra-s in mine the last couple changes.

Aren't the 2008 differentials open all around? If so I'd imagine your goal would be minimizing wear, as I can't see how an oil would appreciably affect behavior -- there would be no noise or binding anyway I don't think? Somebody correct me?
I believe you are correct in the 08's being open all around in WRX trim. They solved the traction equation with fancy monkey motion ballet of traction control and abs modulation. Not sure about 09+ since the minor redesign for 09.

So what the hell should I use in my STI???

I'm actually coming up on needing a tranny fluid change pretty bad....so figured I'd ask.
Extra-s will be fine.

Apparently not Redline LWS. I'd ask your dealer what they use, and go either that way or use Extra-S.
Yeah apparently Redline LWS when I spoke to the redline lubrication engineer, has friction modifiers or something in it that can clog the pump type lubrication on the sti tranny's. I had also heard that STI tranny lubrication pump design has changed to a different type since its inception here, although not having an sti, I have no idea when or why.
 
#354 ·
Aren't the 2008 differentials open all around? If so I'd imagine your goal would be minimizing wear, as I can't see how an oil would appreciably affect behavior -- there would be no noise or binding anyway I don't think? Somebody correct me?
 
#355 ·
So what the hell should I use in my STI???

I'm actually coming up on needing a tranny fluid change pretty bad....so figured I'd ask.
 
#361 ·
06wrx4me.... thanks for the 24 page re-cap, uber helpful and time saving.

I have another question, when should the first change in tranny and diff be for the '11 WRX? That one Cobb article (which apparently they took down), as well as a poster in the 'Change to Syn now' thread, indicate that there is no need to wait to change over....then there are others that post you should run stock till the first 30K to break it all in.

FWIW, I am planning on going Subaru Extra S unless someone thinks there is better to be had....currently stage2, nothing special.
 
#364 ·
I don't think you'll see much of a difference w/ 1st and R w/ a change of fluid- this being my 3rd WRX I've simply gotten used to it :)- now you could see a difference in 1st if your talking downshifting from 2nd w/ a fluid swap, not from a standstill however
 
#366 ·
That time again... The parts store, bless them, didn't have enough of the white label Valvoline regular 75W-90 bottles so I got a bottle of grey Valvoline synth to top off the gearbox (it usually takes a touch over 3 bottles since gear oil is nearly impossible to drain, so I just used the synth for the touch and trust that products from the same firm are miscible -- not that anyone else worries at all about this stuff since people come up with cocktails and such anyway).

The rear doesn't matter anyway so it got M1 this time, since that's what they had and I'd rather use M1 in the rear diff than in my gearbox.

I dutifully used silicone on the rear diff drain plug because I'm a victim that believes everything in the manual, including that a viscous fluid will miraculously leak out of a drain plug tightened to 45 Nm without the magic silicone on the threads.

Car shifts fine.
 
#368 ·
Trying the Mobil Delvac GL-5 synthetic (but lacks friction modifiers) since the Torco GL-6 the tranny shop put in went to hell in a coupla thou miles. About 1500 on it so far and it gets better everyday. Very much like extra-s, but others say it does not do as well in cold temps as the SOA goop.
 
#370 ·
Just replaced my tranny fluid with the stock Subaru Extra-S 75w90 fluid. I went out for a short drive just to test out the shifting. Well, I am impressed with the fluid. Overall I would say the shifting is about 50% better than before. My car is a 2014 WRX with only about 2000 miles. Surprisingly, the stock fluid with only 2000 miles is dirty and there were some fine metal shavings adhered to the magnetic portion of the drain plug.

I put in about 3.7qts and my dip stick now shows the fluid lever a bit over the upper hole. I hope that is ok.
Should I drain out some of the fluid?
 
#371 ·
Just replaced my tranny fluid with the stock Subaru Extra-S 75w90 fluid. I went out for a short drive just to test out the shifting. Well, I am impressed with the fluid. Overall I would say the shifting is about 50% better than before. My car is a 2014 WRX with only about 2000 miles. Surprisingly, the stock fluid with only 2000 miles is dirty and there were some fine metal shavings adhered to the magnetic portion of the drain plug.

I put in about 3.7qts and my dip stick now shows the fluid lever a bit over the upper hole. I hope that is ok.
Should I drain out some of the fluid?
 
#372 ·
When I had the same concern with my 2002 a more experienced member pointed out that the WRX gearbox is not a closed system; it's vented. You should therefore have no problem in a WRX. The STi uses a pump so I'd drain that.
 
#374 ·
Bumping this back from the dead but I think I have some valuable testing information to provide. I did a long-term analysis in my WRX changing the transmission oil every 20,000 miles. I used three oil combinations: 1) 2 quarts redline 75W90NS and 2 quarts lightweight shockproof, 2) 2 quarts Amsoil SVG gear oil and 2 quarts lightweight shockproof, 3) 4 quarts Subaru extra S 75W90 gear oil.

The results are pretty telling. Some of the key categories showed significantly higher levels with the redline/amsoil mixes versus the extra S. Iron and silicone levels were 2 to 3 times higher. Zinc was 2 to 6 times higher. With the mixes Molybdenum and Calcium levels were extremely high, which most likely led to insoluble levels of 2 to 6 percent (not what you want). The viscosity for the mixes were much higher than what you would normally want and the flashpoints would get down to the lower limit or below it.

Basically the subaru extra S hands down beats the mixes. Using a mix in your transmission is not a good long term application, it just masks a current problem and accelerates wear in your transmission. Stick with a single oil that works well for you.

You will also notice that since I could not flush out the transmission the Subaru extra S oil picked up some contamination from the previous mixes that had been used in the transmission as Molybdenum and calcium counts are high after use, plus it was dark in color when I changed in it. I just did a drive train swap on my car so I cant run another test on a second extra S run but I am willing to bet the results would be even better with less contamination from the prior mixes.

 
#375 ·
Repped.

People, rep this user!

This is VERY VALUABLE information.

It goes toward proving what many have suspected all along -- the guru mixes are at best questionable (I'm being lenient). Reports like this should be stickied.

THANK YOU!
 
#377 ·
Sad to read the link. I'll admit, posting what evolved into a namesake "cocktail" online was ambitious on his part. However namecalling and repetition aren't as valuable as actual data as it turns out!

That pic with the nicely layered cocktail components was great!
 
#378 ·
Just changed out the transmission oil of 2009 WRX.

I am sad to say it has never had it done before. I drained some pretty disgraceful looking fluid. There were some metal shavings, some stink and chunks adhered to the magnetic drain plug. The torx T70 was hard to find, but for $20 I found it and performed the change.

I used the glorious Subaru Extra S 75W90 by Idemitsu. I did notice a better feel right away and downshifting into first is quite a bit easier. I am gonna order another batch!
 
#380 ·
Hi!
Is anyone using Royal Purple 75-140? Need some opinions on transmission fluid? What do you use and why.
Blammo is using Subaru Extra S 75w90 is this ideal weight? And which transmission filter? Call me paranoid but I want to change it at 10,000. My job is close to home, I'll have had the car like 4 years before I hit 30,000. Looking for helpful suggestions.
 
#381 ·
Need some opinions on transmission fluid?
See UOAs and opinions, this thread.

Blammo is using Subaru Extra S 75w90 is this ideal weight?
Ideal depends on environment but in general, yes, as this is the works fluid at a viscosity chosen by the works.

And which transmission filter?
None. There is no transmission filter on manual gearbox cars. There IS a transmission filter on automatic cars; it is shaped like an oil filter and is often confused for an oil filter, but isn't. If your car is manual, see this thread as stated. If your car is automatic, DO NOT use manual gearbox lube in your transmission (in other words, IGNORE THIS THREAD). Use the correct automatic transmission fluid and get the correct automatic transmission filter from any dealer.

See whether your drain bolt is a T-70 or a conventional 21mm bolt and have the right socket around. Also see if you have a funnel and tubing that'll prevent you from having to take off the IC (I would not take off the IC for a fluid change and use tubing instead).
 
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