DanUK

Trying to improve the shift on the STI. Not the best gearbox Subaru ever made!
Any additives you guys are using?
Easy enough to do myself?

maci

iTrader: (3)

My 05 sti went back 2 times to the garage as I was really unhappy about the gearbox. They changed oils twice and second time they told me they put in some additive, but I have no clue what. Things have improved(I had problems when shifting 2nd in the morning, when was cold), but is not perfect.
Scoobynet people seems to advice an oil called castrol syntrax, do a search on it.
I will buy some and try it out for sure, but in my case I had just bought the car, and was not willing to pay more, so wanted the gaage to figure it out.

hope this helps

D1CCY

Mines done 46k and is OK with whatever oil Scoobyclinic put in for me when I had a tunnel shaft bearing failure. Presumably a Silkolene product of whatever viscosity the handbook requires. Just patient with 1st and 2nd when its cold, as I'm not in a hurry anyway (till its warmed up).

DanUK

Thanks for the feedback guys. If anyone actually has tried an additive that works can you post it?

ZEN Performance

Redline heavyweight shockproof oil definitely improves the change, although can give a stiff feel to the box until warm. Redline Lightweight shockproof is a little more consistent in the cold, but still gives good shift quality.

If you're box is crunching, go with the heavyweight shockproof, if it's otherwise okay and you want to just improve it, I recommend the lightweight shockproof.

Paul

ScoobyWeb

Paul, What about Redline MT90. I have some of this which I bought for my last car. 2nd gear on mine is a bit tight until box has warmed up.

Chris.