I've recently had my MY2011 STi Saloon serviced at a local Jap Specialist Indy that I've been using for years.

This is nothing to do with him as I sourced my own oils prior to service to save him the hassle.

Now, I plumped for Millers Oils CRX 75W90 NT Competition which is a GL5 oil which is specified in the handbook and is the correct grade.

I went for Millers because I have used their oils in my old Honda CTR (FN2) and couldn't fault them, however in the STi if the car has been stood for more than 4-5 hours then first and second gear are very hard to select for the first 5-10 minutes of driving. With first you have to pretty much come to a complete stand still before it will engage, going up to second is OK but a bit stiff and you get a bit of dragging into third. Going down from third you need to rev match to get it to go into second or it just won't have it at all.

When the car has warmed up, it's spot on. Nice and slick and changes freely. I've done 250 miles and driven the car in temps ranging from 3C to 11C in the mornings and it's the same regardless of ambient temps.

The service I had was engine oil and transmission oil (inc rear diff) and we're doing brake fluid after Christmas as the front pads and discs are getting on for needing replacing, so it could only be the change of transmission oil that has caused this. It wasn't amazing before the service but it was definitely better than this.

I don't know if it is a 2008/2011 gen specific issue, but it doesn't like these gearboxes when cold.

I'm very probably going to get the oil swapped out again when I get the front brakes done after Christmas, so the point of this thread:

What should I swap it out for and would it also be worth doing the rear diff oil, which also has this oil in now. I'm specifically looking at 08+ hatch and 11+ Saloon owners!

 

I have the exact same problem in a widetrack blob, gear change was perfect befor the oil change, went for the same oil as you.

tried motule 300, which wwas a tiny bit better, also tried redline ns.

Nobody seems to know which oil they put in at the factory.

 

we use Mobil one Mobilube HD 75w90 from Subaru themselves

http://www.mobil.com/Germany-English...HD_75W-90.aspx

 

I've had the oil changed out about a week ago for Motul Gear 300, both in the gearbox and the rear diff.

Miles better, amazingly so. Back to enjoying the car again!

 

stick to semi synthetic in the 6 speed castrol driveline etc, the fully synthetic are too slippy for the syncros combined with cold temperature .

 

I've not used Millers so can't comment on that, but i do remember John Felstead posting something about the Millers not liking cold weather.

See post #29 -> https://www.scoobynet.com/drivetrain...6349-dccd.html

Motul Gear 300 has been proven to work very well with 5 and 6MT Subaru gearboxes. You don't want to put gear oils that have LSD additives as that would be too slippery for the synchros to work. I don't think it's so much a case of full syn gear oil being too slippery, as the Motul Gear 300 is fully synthetic and is serving you well.

Your MY11 STI Saloon would have the Torsen rear LSD, so you don't need a LSD specific oil. A quality GL5 gear oil like the Motul Gear 300 will do.

Regards
Errol

 

would this suit a dccd box too?