2014 Subaru rear diff oil change.

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JTK

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I'm just over 30K miles on my 2014 XV Crosstrek 5spd and decided to swap the rear diff gear oil yesterday.

I picked up some Supertech semi synthetic 75w90 and had at it. It was as easy as can be. Plenty of room underneath given the fair amount of ground clearance. All you need is a 1/2" ratchet handle to remove the fill and drain plugs. The drain plug has a big magnet on it that had a glob of black metallic paste on it.

I was kind of surprised to only get about a half quart out from the factory. I re-filled until oil started to dribble out the fill plug hole, which took a quart. Put the plugs back in with never-seize on them and was done in minutes.

Next will be changing the oil in the 5spd..
 
I agree. I don't recall my RS rear diff taking anywhere near what they said it used.

Careful what you put in the transmission. Unless things have changed, Subaru manual transmissions are VERY picky. I wouldn't bother using anything but Subaru's own Extra-S. Many have experimented over the years and Extra-S always ends up being the best choice.
 
Extra-S is only available in 5-gallon buckets.

There is a newer Subaru-branded 75w-90 that dealers have in quarts. It's okay.

Red Line 75w-90 NS and Motul Gear 300 75w-90 are good choices.

I found Amsoil Severe Gear to be a poor choice in the transmission.

I'm going to stick with Supertech, changed out at shorter intervals.
 
Originally Posted By: Bandito440
Extra-S is only available in 5-gallon buckets.

There is a newer Subaru-branded 75w-90 that dealers have in quarts. It's okay.

Red Line 75w-90 NS and Motul Gear 300 75w-90 are good choices.

I found Amsoil Severe Gear to be a poor choice in the transmission.

I'm going to stick with Supertech, changed out at shorter intervals.


Fred Beans Parts take the Extra-S from the 5 gallon bucket and bottles it in their own 1qt jugs.
 
Originally Posted By: Bandito440
Extra-S is only available in 5-gallon buckets.

It's now available in quart bottles at dealers. It's not labeled as "Extra-S" though.

http://parts.subaru.com/p/Subaru_2014_Le...OA427V1700.html

SOA427V1700.jpg
 
I once owned a 2007 WRX I bought new. It had the five speed manual which comes up with a scary result if you google glass transmission. I used nothing but SuperTech semi synthetic 75W90 since it's first fluid change until I sold the car with over 130K on it. The shifting was great and the transmission held up to my stage 2 Perrin tune. I wrote about this fluid on here long ago. The thing that makes this particular fluid so good in certain applications is it lacks the friction modifier for use in limited slip diffs. A fluid touting it's use for limited slips makes for a bad shifting manual gearbox. Don't worry, the Crosstek doesn't have any clutch packs which would warrant another fluid.
 
Originally Posted By: artificialist
Fred Beans Parts take the Extra-S from the 5 gallon bucket and bottles it in their own 1qt jugs.
Not anymore. The stuff they advertise as Extra-S will arrive as quarts of Subaru HPGO. This is a different formula.
Originally Posted By: y_p_w
It's now available in quart bottles at dealers. It's not labeled as "Extra-S" though.

http://parts.subaru.com/p/Subaru_2014_Le...OA427V1700.html

SOA427V1700.jpg

This is the new stuff. It's a different formula from Extra-S.

Subaru gear oil VOAs
 
There was a thread on another forum about this a while back with the CVTs and the differentials. Some said they drained at 40,000 miles and it still visually looked good. I have 38,000 on my 2012 Legacy and will wait until 50K.
 
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Yeah, I have read where the front diff oil on AT/CVT equipped Subarus is barely discolored on it's first drain. That's one nice thing about the 5MT. It's all lubed by the same 75w90.

The rear diff oil didn't look that bad at 30K miles. It was darker and had a sheen to it.
 
I have a 2014 WRX and changed out the rear and shared trans/front with Amsoil 75W-110 SVT at around 2000 miles. The shift feel improved immensely. Some of the people on NASIOC said any type of synthetic gear oil would be OK at first, but would rapidly degrade. So far at around 15K miles, no different than new fluid, no different, hot or cold. I did slightly overfill it. I have come to the conclusion that synthetic gear oil is fine, but not the under 15-16 cSt 75W-90 variety.

As for the rear, yes it holds so little, 75W-110 is a good bet. I've been meaning to climb under with my IR thermometer to check it after a hard run - before the weather gets too cold.
 
Yeah, I only got a half quart out of the rear diff, but it took a whole quart before it started to dribble out the fill hole.
 
The only problem I had when changing the rear diff fluid on my Forester is that the plugs were in so tight I had to take it to a shop for the first change. After that they were fine.
 
Originally Posted By: Pablo
I have a 2014 WRX and changed out the rear and shared trans/front with Amsoil 75W-110 SVT at around 2000 miles. The shift feel improved immensely. Some of the people on NASIOC said any type of synthetic gear oil would be OK at first, but would rapidly degrade. So far at around 15K miles, no different than new fluid, no different, hot or cold. I did slightly overfill it. I have come to the conclusion that synthetic gear oil is fine, but not the under 15-16 cSt 75W-90 variety.

As for the rear, yes it holds so little, 75W-110 is a good bet. I've been meaning to climb under with my IR thermometer to check it after a hard run - before the weather gets too cold.

Amsoil Severe Gear differential fluid is probably the best.

Unfortunately Amsoil doesn't recommend it for 2000 MB E430.

Amsoil website: "No AMSOIL Product Recommendation" "Use MB Part# 001 989 33 03 or 001 989 17 03 or equivalent approved products listed on MB Sheet 235.7".

For 2004 Honda S2000, I have 2 remaining quarts Honda MTF P/N 08798-9031 I bought few years ago from a local Honda dealer for dirt cheap (I used $25 Christmas coupon to buy 4 quarts at $6.xx/qt), I may need 1 quart Severe Gear 75W-110 SVTQT (capacity is 1.5 pints).

Will you contact Amsoil engineering dept to see if they think either Severe Gear 75W-90 or 75W-110 is suitable for 2000 MB E430 sedan(standard, not 4-MATIC).

I like to buy gear fluid for both cars(capacity: S2000 1.5 pints, E430 2.3 pints) to save shipping cost. If both cars can use either Severe Gear 75W110 or 75W-90 will be great(I need 2 quarts for both cars).
 
Originally Posted By: Nate1979
The only problem I had when changing the rear diff fluid on my Forester is that the plugs were in so tight I had to take it to a shop for the first change. After that they were fine.


I was expecting this, but got lucky. It only took a smack to the ratchet handle for them to break free for me.
 
Originally Posted By: HTSS_TR

Will you contact Amsoil engineering dept to see if they think either Severe Gear 75W-90 or 75W-110 is suitable for 2000 MB E430 sedan(standard, not 4-MATIC).


Request sent.

Also, I actually used the correct tool on my rear diff, with a breaker bar and extension had no problem.
 
Originally Posted By: Pablo
Also, I actually used the correct tool on my rear diff, with a breaker bar and extension had no problem.


13.1mm square? I'm surprised anyone in the USA uses them.
 
I believe it was a 13.1mm square, sounds about right. Had to use a nice sized breaker bar on my '14 cranked with another floor jack before the plugs on mine popped loose. Those plugs are on there nice and tight.

The rear diff fluid in our '14 was black as night at 8K. While I flogged it during break-in I think the color was due to some sort of moly based assembly paste/lube they used at the factory. Didn't do an analysis so this is just speculation on my part. The front diff was still a nice amber color at 8k.
 
Originally Posted By: Pablo
Originally Posted By: HTSS_TR

Will you contact Amsoil engineering dept to see if they think either Severe Gear 75W-90 or 75W-110 is suitable for 2000 MB E430 sedan(standard, not 4-MATIC).

Request sent.

Thank You Pablo.

Hoping that there is an Amsoil differential fluid for my '00 E430.
 
Rear diff should be just under a quart. 13 mm sq but 1/2 inch works. Don't impact with a 1/2" or you will no longer have a sq. hole.

I always use Mobil 1 75W-90
 
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