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.

 

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

 

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.

 

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

Why is this not recommended for the 6 speed box?

 

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...

 

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

 

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!

 

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.

 

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

 

Bingo..........

 

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

 

Anybody

 

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.