Topic: 2015 WRX - Transmission Oil Recommendation

[CalgaryWRX]

Hi Guys,

I have a 2015 WRX with 85K on the ODO, the transmission prior to the new 75w90 fluid was perfect; it shifted perfect, never grinded a gear, syncros were always smooth! My car drove like it was brand new!
A week ago, I choose to replace the factory gear oil with Redline 75w90NS and now I feel it is also harder to shift into gear, kind of like a notchy feeling as the shifter slides into gear... This happens when the car is cold. Once it warms up it drives pretty good.

I am now looking to ditch the Redline 75w90NS, but I am stuck on what I oil I should use... Centaur Subaru no longer offers Subaru 75w90 in 1-5 liter containers and they want something like $280.00 to replace the transmission oil...

What is everyone's preference for GL-5 gear oil that does not contain limited slip? Anyone try Mobil1 Delvac 75w90?

Thanks,
Rolland

[CalgaryWRX]

I picked up a case of Mobil1 Delvac 75w90 GL-5 synthetic today for only (12 X 10.79/L) :O

This oil lacks the standard friction modifiers found in the standard Mobil1 75w90LS and Porsche owners on Amazon.com are ranting and raving about how much they like this oil in their transmissions! I also found a few positive online reviews from Outback and Forester owners happy with this oil.

I'll be swapping out the Redline 75W90NS in the next few days and I will report back my findings!


Thanks,
Rolland

[10secdream]

The Subaru stuff is pretty much perfect but the Motul Motyl Gear was almost as good.

[kijho]

I used Motul

[jellynuts]

Yup, I'm also on Motul MotylGear 75W90 since 2016.  It's notchy when cold, upshifts are ok, but it fights downshifts until it warms up. 

This site still offers Subaru oil?  I've never bought from them:

https://www.ft86motorsports.com/subaru-75w90-high-performance-gear-oil.html

[CalgaryWRX]

Bad news!

I drained the Redline 75W90NS "No Slip" and the fluid color looked good, but there was a lot of small metal particles suspended in the oil and a few larger metallic chips which sunk to the bottom of my drain pan. There was a light metal film left on the magnetic drain plug which I recently cleaned off two weeks ago. Driving with the Redline was always notchy and downshifting was poor, but I never grinded a single gear. I hope that I didn't do any long term damage from using this oil... My belief is that the Redline being a level 4 synthetic oil, is a great diff oil but not so great of a transmission oil. The "no slip" oil is just too slippery for the syncros despite Redlines claim that this oil lacks the standard friction modifiers. I read an Amsoil white paper on testing gear oil and the Redline failed horribly at controlling foaming. 

www.lastgreatroadtrip.com/wp-content/uploads/2010/11/gear-oil-comparison.pdf


Good news!

I am absolutely ecstatic with the Mobil1 Delvac 75w90! I would proudly say that it even shifts more effortlessly and smoother than when the car was brand new! All the notchyness created from using the Redline 75W90NS oil is gone, it just slips into gear! Down shifts into second gear and first gear is perfect! I could not be happier driving around this morning, I just wanted skip work to drive a bit longer!!!

Mobil1 Delvac 75W90
$10.79 a liter
https://www.mobil.com/English-US/Commercial-Vehicle-Lube/pds/GLXXMOBIL-DELVAC-1-GEAR-OIL-75W90

Mobil Delvac was purchased from Miller Supply, located outside of Okotoks and my order was placed via email
www.millersupply.ca

[jellynuts]

Awesome!  Thanks for the update.  Give a long term update too if you ever think of it.

[nemohm]

75w90NS means "no shock, as far as I remember.

C.Tire might still have gear oil rated GL-4/GL-5 - works pretty good.
Otherwise - 1l Redline MT-90 (GL-4) and the rest is 75w90NS - works pretty well too

[VTAKLOL]

75w90NS means "no shock, as far as I remember.

C.Tire might still have gear oil rated GL-4/GL-5 - works pretty good.
Otherwise - 1l Redline MT-90 (GL-4) and the rest is 75w90NS - works pretty well too

It’s “no slip”, as stated above, meaning it does not have the LSD friction modifier.

[CalgaryWRX]

Awesome!  Thanks for the update.  Give a long term update too if you ever think of it.

I just hit 10K on the this new Mobil Delvac oil and it still shift awesome! I am loving it!

[nemohm]

If somebody has an extra Mobil1 Delvac 75W90 - I'm interested.
Interested in sharing new case as well.

[TenTurbo]

Thanks for the update on that Mobil Delvac Rolland! A local speed shop used some stuff that I don’t remember now when they installed my new clutch in Sept. Shifts great except for downshifting into 1st at low speed (ie: 2nd into 1st at 10-15 km/h). Shifter just feels “locked” and won’t push up into gear. Sometimes have to slow down further to 5 km/h just to get it to go in. Still inexperienced with these cars so maybe this is normal.

[RockThePylon]

Thanks for the update on that Mobil Delvac Rolland! A local speed shop used some stuff that I don’t remember now when they installed my new clutch in Sept. Shifts great except for downshifting into 1st at low speed (ie: 2nd into 1st at 10-15 km/h). Shifter just feels “locked” and won’t push up into gear. Sometimes have to slow down further to 5 km/h just to get it to go in. Still inexperienced with these cars so maybe this is normal.

Eh, my Subarus have always been like that. I just made it a point to get good at double clutching into 1st.