Scooby_nz

A mate of mine has a 54 widetrack STI Type UK and the gearbox has started to grind when engaging 6th even during normal driving. 4th does it if higher in the rev range or shifting down.

Will a gearbox oil change help this? Read a little about the redline shock proof oil but not too sure

All help appreciated.

Ste333

iTrader: (3)

Mines started to do it a little bit when high revving from 4th into 5th. But then my clutch is a bit tired now. Could be clutch related mate....

A gearbox oil change is worth doing anyway if it hasn't been done for some time. Then gauge it from there. Just use a good quality oil - Motul, Redline etc

dazdavies

iTrader: (22)

Do not put Redline shock proof in a six speed box. It's horrible stuff.
It could be the synchros are on their way out but an oil change may just resolve your issue.

Scooby_nz

A lot of people actually have used this and are happy with the results!

Why is this not recommended for the 6 speed box?

JGlanzaV

iTrader: (3)

I have the lightweight shock proof in my 6 speed. The box is ****ed anyway, so I thought Od give it a go.... Cant say I noticed any difference...

Scooby_nz

Is your box completely knackered or just grinding in a couple of gears at high revs?

JGlanzaV

iTrader: (3)

Grinds on up and down shifts at mid to high rpm....

its a common problem on the 6 speeds this is the 2nd one I have had break on the same car.

redline shock proof hasnt helped, a very expensive way to find out its no good!

plenty

iTrader: (13)

I had a MY04 JDM six speed which was slightly crunching from third to fourth. Following a tip on a US forum I changed the oil with a blend of 50% Lightweight Shockproof and 50% Millers 75w90. Presto - solved the crunch completely.

JGlanzaV

iTrader: (3)

The crunch isnt solved. It is masked.... big difference

AS Performance

iTrader: (4)

Bingo..........

Scooby_nz

Thanks for all the replies.

I have driven this car myself today have noticed that the clutch is biting quite near the top however there is absolutely no slip.

Could the cruching be the be the fact that the clutch is on it's way out?

Thanks

Scooby_nz

Anybody

Arch

iTrader: (59)

Think you already the the answer its most likely that the synchro's are worn. You could try something like a millers 75W140 NT which may help but as mentioned it's not going to sort it.