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Do you change your Trans Fluid

  • Yes

    Votes: 51 75.0%
  • No

    Votes: 4 5.9%
  • I like to eat glue

    Votes: 13 19.1%
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1996 GC Black
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163 Posts
Discussion Starter · #1 ·
I was hoping to get a poll of how many Subaru owners actually change there Tranny / Rear Diff fluid.

My question to you all is:

What are your feelings on replacing tranny/ rear diff fluid?!?!?! Ive talked to a couple of Subaru Mechanics and both said that the "tranny" / "Rear diff" will last the life of the car, that there's no point in replacing it. I was told its a "sales gimmick" more than an actually need.

What are your Opinions?!?!?!?

:corn:
 

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Premium Member
2001 A.W. L
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13,249 Posts
I replace mine every 30k miles... (Per the service manual)

Oil breaks down after use, it also gets dirty. Not changing it is a bad mechanics way of getting a transmission overhaul job down the line.
 

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'99 2.5RS RBP
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10 Posts
Oil breaks down after use, it also gets dirty. Not changing it is a bad mechanics way of getting a transmission overhaul job down the line.
Some fluids in cars are designed to last the life of the car. Ex: The New Venture NV4500, NV5600 transmission in the 3/4, 1 ton Dodge trucks use Castrol Syntorque and are a lifetime fluid. They have a sticker stating that the only reason to remove the drain plug is when the transmission is being serviced. Some coolants in newer cars are also designed to function for the entire life of the car.

All fluids are designed to break down at a certain rate. This is why the manufacturer provides maintenance intervals for most every wear part on the vehicle.

To the OP: Follow what the Factory Service Manual states. The manufacturer of the car will know best.
 

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'00 Impreza 2.5RS sedan white
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84 Posts
I changed to Redline synthetic oil. I'm having a little grinding when shifting to 5th. Redline has worked very well in a couple of other transmissions that helped ease a similar issue.
 

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00'RS/02' WRX stgEleventy
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2,144 Posts
Subies do not have lifetime fluid in them.. ask the guy that picked up a 200k forester that likely had the stock charge in it..yay..

It doesnt break down nearly as fast as engine oil but it does break down..

My suggestion would be Subaru Extra-S in the trans and rear diff.. order 5qts (from fred beans for instance) and youll have enough for both

Sent from an other planet (Tapatalk)
 

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Lexus LX470..
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290 Posts
I'm about to change my transmission fluid and was recommended Uncle Scotty's Coctail Mix. Just search NASIOC for it. It's only for 5 speed manual tranny's but there's so many people who've used it that I've decided to give it a go
 

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2000 2.5RS/C BRP
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2,321 Posts
I'm about to change my transmission fluid and was recommended Uncle Scotty's Coctail Mix. Just search NASIOC for it. It's only for 5 speed manual tranny's but there's so many people who've used it that I've decided to give it a go
This is what's currently in mine. I did notice a slight improvement in shifting smoothness, and the 5th gear grind went away completely, but the shifts have gotten worse even so. Next time I'm going to try the Redline 75W-90NS.
 

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00'RS/02' WRX stgEleventy
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2,144 Posts
I'm about to change my transmission fluid and was recommended Uncle Scotty's Coctail Mix. Just search NASIOC for it. It's only for 5 speed manual tranny's but there's so many people who've used it that I've decided to give it a go
I had that cocktail in my one car about as long as it took for me to get Extra-S in the mail.. did not like..

Sent from an other planet (Tapatalk)
 

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1996 imp jdm ej20 NA dohc swap
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400 Posts
Take apart a 5 spd subaru tranny with 150k plus miles with no fluid changes and see what it looks like.... :eek:

Then run your finger through the grime... will make you or anyone else think twice about not changing the fluid... :lol:

I have seen a number of fluids work in these subaru 5 spd trannys. Straight valvoline 75w90 none synthetic, a mix with 1 quart pennzoil synchromesh, redline 75w90NS, a few cocktails, motul 75w90 has worked in some as well and the OEM subaru extra-S of course.

I am going to give the 2.75 quarts valvoline 75w90 NS and 1 quart synchromesh a try since the tranny has over 150k on it. If it does ok then I might go for the extra-S in the fall or stick with the blend but we shall see.

30k-40k miles for tranny and rear diff drain and fill is cheap insurance.
 

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'04 PSM WRX Premium
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8,339 Posts
Subaru Extra-S for me. It didn't change the feeling of the car at all really. Previous owner looks to have kept it decently clean. It should still be done though. 30k is the max IMO.

It'll save you time and headaches down the line and isn't that expensive.
 

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2000 GC67 Sliver 5 speed
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307 Posts
Mine felt like it was binding somewhat coming out of gear during fast shifts. Change the gear oil and felt fairly improved. I did not use extra-s at the time because I did not know about it but I will next time to see if it will feel even better. Most people I think don't even know transmissions need oil. Maybe I am wrong but talking to people in the past about it, then they proceed to give me the :wtf: expression like i'm crazy.
 

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Y2K GM6 & 65 'Stang Fastback
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818 Posts
As a Master Auto Tech, it is my professional opinion, there is no such thing as a lifetime fluid. Most brand new from the factory call it that because the fluid will probably outlast the ownership of the first buyer. Now, I know some will challenge that and have other opinions, however, changing fluids is also cheap insurance. I can handle 50-100 to change the oil in my trans and diff, buying a used trans and diff, then you might run into the same problem again. Not worth it to me.
 

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my98 ver4 STi wagon
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87 Posts
I just changed my rear diff fluid with motul 300. I didn't have the car leveled when I poured the fluid and I've seen a few posts say the car has to be leveled. I kept putting fluid in until it started to spill.

Does this mean my diff doesn't have enough fluid?
 

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1996 imp jdm ej20 NA dohc swap
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400 Posts
I just changed my rear diff fluid with motul 300. I didn't have the car leveled when I poured the fluid and I've seen a few posts say the car has to be leveled. I kept putting fluid in until it started to spill.

Does this mean my diff doesn't have enough fluid?
On level ground not jacked up, the level of fluid should be just to the bottom of the top fill hole. So around 0.8 of a quart. Most likely have too much in there if it has spilled out some.
 

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2004 2.5rs-pacifica blue pearl
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425 Posts
Subies do not have lifetime fluid in them.. ask the guy that picked up a 200k forester that likely had the stock charge in it..yay..

It doesnt break down nearly as fast as engine oil but it does break down..

My suggestion would be Subaru Extra-S in the trans and rear diff.. order 5qts (from fred beans for instance) and youll have enough for both

Sent from an other planet (Tapatalk)
For the record, the oil Fred Beans sells is NOT Extra-S it is the replacement...

there have been VOA done and posted on that "other" site and proved they are NOT the same!

Also Extra-S was made by some subsidiary of shell, the HPGO is made my idemitsu

Not to say the new "High Performance Gear Oil" shouldn't or can not be used but everyone seems to think it is Extra S!

Including myself up until a few days ago!

I bought some myself. Already used and didn't notice any problems.

I will continue to use it for my RS diffs but I am going to be buying Motul for the STi from now on.

My gearbox got frozen every single night over the winter...

Hoping Motul doesn't get too thick in cold temps..

Subaru Extra-S for me. It didn't change the feeling of the car at all really. Previous owner looks to have kept it decently clean. It should still be done though. 30k is the max IMO.

It'll save you time and headaches down the line and isn't that expensive.

Curious, where did you source your "Extra-S" From?

I can't seem to find the 5 gallon pails anymore...

subaru has super-seeded the Extra-S with the "HPGO" and it is now only available in QTs, the dealers receive them in cases of 12.



To the OP,

change your fluids!

it's fairly cheap and easy!

if you have 4eat, use the subaru ATF, maybe throw some trans tune in first before you change it and drive a day or two to clean things out

you will only be able to drain 4ish Qts out of the pan, most like to drain and filll, then do another drain and fill at the same time as there next 2 oil changes as there are 12qts total so 3 drain and fills, should roughly mean you have all new fluid, you will still have some old stuff left in there tho

use 75-90 gear oil for front + rear diffs if they are not LSD

I would buy the "HPGO" from fred beans, or cough up the extra cash for Motul.

If you have LSD rear, I thikn fred beans also sells a Subaru LSD oil or once again you can get Motul

you need 2 qts total for F+R diffs but buy 3 in case you spill some!


If you have 5mt
,

front diff is one unit with 5mt so you need roughly 4-5 qts I think, look it up

use 75-90, same options as above...

lots of 5mt owners say the 5spd really likes it's syncromesh, most say a 1/2qt mixed in is enough!



Ok hope that helped!


NOW CHANGE THE FLUIDS!


EDIT: WOW this was posted 3 years ago! EFF ME!
 
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