2008 Subaru Impreza WRX 5 Speed Manual Trans

[FMC]

A friend of mine has a 2008 Subaru Impreza WRX 2.5L turbo with 5 speed manual trans, 75,000 miles. He feels it's a little hard to get it into 1st gear even when stopped, so as a preventive maintenance wants to change the manual trans fluid, the Subaru spec is GL-5, but he has read on the Subaru forums that people are having better results with GL-4.

Does anyone have any insight into why this may be ?

Any recommendations on what quality products to use ?

Thanks

 

[2oldtommy]

Clutch may not be releasing completely. Check the fluid level in the slave cylinder for proper level of fluid. It may need to be blead if it is low. FWIW--Oldtommy

 

[Rand]

The front diff shares the oil with the MT you NEED to use GL-5 Gear oil for the gears.

the transmission itself would be happier with GL-4 but again the actual front diff.. shares the sump.. its a not so good design choice.

He could start by trying walmart supertech 75-90 GL-5
or redline 75w90 NS..
or a similar 75w90gear oil with no friction modifiers.

Some people like the subaru Extra S 75w90 gear oil.

In my 5MT it was not so good. although some people say its better in the 6MT


also its really hard to change the front end gears in that transmission.. its usually cheaper to replace the transmission with a used one.. so you REALLY want to keep them happy.. ie no gl-4

 

[LoneRanger]

Don't use a gear oil with friction modifiers for limited slip differentials.

Supertech Semi-synthetic 75W90 GL-5 works great in my Forester's manual transmission. I've had it in for 16,000 miles now. I can downshift into 1st from 20mph without much effort.

 

[oggb]

I'd always told myself that if my WRX started developing shifting problems I'd change the gear oil out with a 70/30 mix of cheap Valvoline 80w-90 and Pennzoil Synchromesh.

Look up "Uncle Scotty's Cocktail". One of the main (and more important) ingredients is Pennzoil Synchromesh.

 

[Xstang]

Originally Posted By: Rand
The front diff shares the oil with the MT you NEED to use GL-5 Gear oil for the gears.

Some people like the subaru Extra S 75w90 gear oil.


This is the answer IMHO. Ask a dealers parts counter for it.

 

[stephen9666]

How much is the OE fluid?

I've become an OE tranny fluid convert. I got tired of trying different brands. The OE fluid may cost a little more, but it will meet the specs and has worked better than any aftermarket fluid I tried in my Nissan.

 

[PZR2874]

Originally Posted By: JRed
I'd always told myself that if my WRX started developing shifting problems I'd change the gear oil out with a 70/30 mix of cheap Valvoline 80w-90 and Pennzoil Synchromesh.

Look up "Uncle Scotty's Cocktail". One of the main (and more important) ingredients is Pennzoil Synchromesh.


USC turns acidic and needs to be changed out every ~10-15K miles

AndrewTech has a cocktail.... look that one up.

The Subie Extra S always did my 5spd nicely.... Till my gears grenaded

 

[waltb]

I have also used Coastal 75W-90 GL-5 oil in my 2008 Outback 5spd that has worked great. Like the Supertech Semi-syn oil, the Coastal also says that it is NOT for use with Limited Slip differentials. In my opinion this is what you definitely want

I tried other GL-5 gear oils that had the Limited Slip additive included and they all resulted in "crunchy" shifting.

 

[FMC]

What do you guys think about this Shell Spirax S5


Shell Spirax

 

[PZR2874]

Not being able to get into first until stopped is about right (normal)

Have him get the Subie Extra S

Does he auto-x or drag it ?

 

[Strakes]

I had a Subaru Legacy GT with a manual transmission. Subaru Extra-S is what you want. And I tried everything...the extra s is the way to go. It's GL5 and has the best shifting feel.

 

[meep]

he really shouldn't be trying to grab first until almost stopped. It's a lot for the syncros to grapple with, and they will wear from it. Only way I'd ever recommend it is with good rev-match technique with a dbl-clutch shift.

m