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Oil to use in 6 spd gearbox and rear diff?

PostPosted: Mon May 09, 2011 10:45 pm
by PAZ04U
hey guys,

my 50k kms service is coming up and i was just wondering if anyone can recommend some good gearbox and rear diff oil? has anyone put a different type to the standard oil and found it was better?

would love everyones input.

Cheers, Alex.

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Mon May 09, 2011 11:23 pm
by teK--
Very happy with Castrol Syntrax 75W-90 in gearbox and rear diff. Much smoother high RPM shifts and generally better shifts when oil is hot.

Regular fill is Castrol Multitrax according to local Subie dealer.

Suburu boxes are very particular about oil type and additives etc, since it is rather unique in that the front diff and synchros are immersed in the same oil so you need something that both is slippery for the gears but also allows grip for the synchros to work.

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Tue May 10, 2011 12:16 pm
by 3rspecb
teK-- wrote:Very happy with Castrol Syntrax 75W-90 in gearbox and rear diff. Much smoother high RPM shifts and generally better shifts when oil is hot.



+1 and I got 6 speed box..

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Wed May 11, 2011 2:53 pm
by PAZ04U
Ok thanks guys I'll keep that in mind..

What and the TB STI boys? What have you guys used?

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Wed May 11, 2011 3:16 pm
by coyote
In the past I have used Syntrax, Redline and just about every top shelf gearbox oil suggested for Subarus.

I now use Motul Gear 300 and LOVE it. Cold performance is brilliant, yet the high temp shear strength of this stuff is top notch.

Only downside is the cost.

My gearbox is identical to the one in your TbSTi, except yours has to deal with about 100kw less power.

Rear diff doesn't matter. It's a Suretrac diff, so any 75W90 (even the Motul if you're feeling wealthy) will do. It's a limited slip diff, but you do NOT want to use LS additives.

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Wed May 11, 2011 3:42 pm
by PAZ04U
Look I don't really care about cost of the oil etc I just want something really good cause I like looking after my car.. :D

So the motul stuff is good ay? My mechanic told me to look in the motul products for the gearbox and diff.. How many litres does the gearbox and rear diff take? And the rear diff oil is it just motul 75w90 diff oil?

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Wed May 11, 2011 8:43 pm
by Dropz
Yes Motul 75W-90 Diff Oil is what you want in the rear diff. The rear diff takes approx 1 litre and the gearbox is approx 3.5 litres.

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Wed May 11, 2011 9:07 pm
by Kekotic
Removed.

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Wed May 11, 2011 9:20 pm
by Dropz
The clutch fluid?

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Thu May 12, 2011 9:10 pm
by fatfrog02
Hope this is not a silly question, but is the gear box sump plug a generic bolt or does it have to be specifically from Subaru?

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Thu May 12, 2011 10:29 pm
by teK--
It's got a magnet in the bottom; as long as the thread and pitch is the same don't see any reason why generic wouldn't work. Some of the subaru ones are a bit of a bitch anyway it's a huge big torx head I'd love a regular hex to put a socket onto it.

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Thu May 12, 2011 10:48 pm
by Dropz
Torx bit is a t70 size. Not found in many Torx kits, I bought one separately, it was $20 bux! Some older subarus have a 21mm hex bit, but the thread is a bit shorter. Not an issue though lol, still does up fine.

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Thu May 12, 2011 10:51 pm
by teK--
Yep the gorillas at the stealership must have set their rattle guns on super high. It took a lot of swearing to crack that torx nut open; I ended up stripping it a little bit.

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Fri May 13, 2011 1:07 am
by Dropz
Front diffs and gearboxes are always wicked tight. I just get my big bar on them, 600mm :)

Re: Oil to use in 6 spd gearbox and rear diff?

PostPosted: Tue Jun 14, 2011 2:56 pm
by jeffas4966
Redline all the way for me