dkes

I've had the 2004 wrx (totally standard, 43k miles/ for two weeks now, after about a week of ownership the gear change into fourth during fast/high rev driving has become clunky and grinds now and then. If driving sensibly it is fine, but still feels different to all other gears.

Any ideas? Is it a gearbox or clutch problem? Or a known issue?

Splitpin

Worn synchro.

bioforger

iTrader: (1)

More likely a worn clutch.

Splitpin

On what basis? Grinding on gear engagement suggests that the clutch isn't disengaging fully. Worn clutches disengage too easily so the symptoms here are contrary to your diagnosis.

In addition, a problem caused by a worn clutch would affect every gear more or less equally, and there's also no report here of slippage under acceleration. Therefore, nothing there to suggest clutch.

bioforger

iTrader: (1)

Because I saw it in my old classic after a remap/dyno session, which wore out the already worn clutch, third would clunk on every change as well as the obvious slipping. His car is standard there is no reason why the synchro should be worn out imo.

dkes

any tests I can do to figure out if it's synchro or clutch?

I've got a 3 mth warranty on the car so can hopefully get it repaired under that,

Splitpin

To check for a worn clutch, find yourself a reasonably steep hill that you can drive up in fourth or fifth and give it some beans on the way up. If the clutch is gone/going you'll see and feel it slip - the revs rise without commensurate acceleration. If the clutch doesn't slip, you know the problem's elsewhere.

dkes

ok I'll give that a go
cheers

Setright

HANG ON!

It's quite a normal Subaru gearbox "trait". It will cured very easily: Just drain out the old gear oil....refill with Valvoline Synpower 75W-90

Drive, maybe 50-80 miles and the old oil will be washed off the synchro rings...and the shift will smoothen out.

Nothing is worn out...except the oil.


Valvoline was recommended to me by a rallying man, who drives Subarus. It cured the crunch in my Impreza...countless others...and my 20 year old Alcyone Turbo.


PLEASE try this simple and correct fix, before you spend time and money on the clutch and gearbox innards.

vash

I had this issue on my 03 STI 6months in and had exactly the same symptoms as described..

Took it back to the dealer and they had to replace half the gearbox..

If you are under warranty get it back and let them sort it out.

apac

iTrader: (2)

That's odd because when i recently changed my gear oil i started getting a crunch in 4th. So complete opposite to what you've said.

If it only happens at fast driving/high revs then it's because the speed matching of the gears is not working and this is the job of the synchro ring. it lines up the gears for a smooth transition/change

evoke

iTrader: (6)

Same problem when I had my Type R but it was the 3rd gear. It turned out to be a synchro had worn. I had 2 options, have a new synchro fitted or have the current synchro's reconditioned, I went for the recondition & it was fine after.

Hope this helps