Gearbox leaking

Roadrunner · Postby **Roadrunner** » Sat Nov 26, 2016 3:12 pm

Hi all, I've been hunting a faint gearbox oil smell when the car is pushed hard and have just found the problem, but unsure of the source.
This is the leak, front of car is to the left side of photo.
It's not dribbling down the drivers side, only the passengers side.
Before I wiped it all down I reached right up to the top of the casing and it's wet up there too. Obviously I can't see up there so is there something on top of the casing that is leaking? A vent of something?

Any ideas what's going on?

thehillsarecalling · Postby **thehillsarecalling** » Tue Dec 20, 2016 10:07 am

It is likely that the 4 bolts that hold the shifter turret to the casing have come loose, and oil is leaking out between these two components. They seem to come loose with driving (probably the action of the shifter), and even after torquing to spec, they still seem to back out (or at least they do on the cars I've worked on). I always blue loctite them in place now to prevent this.

Also, there's meant to be a gasket between the two, and I've seen a couple of cars that have been missing them for some reason. Buy one from Mazda before you do this job. You get into this area via the centre console - there's guides online on how to get it apart and do this job. If you can't find one, let me know and I'll write one.

FYI 5 speed owners, this doesn't seem to be an issue on the 5 speed box, but you should still get in there and replace your turret oil which hasn't been done in 200,000kms because it's not a scheduled item. And also FYI to 6 speed owners, you don't need to do this because your transmission has one oil gallery which lubricates both the turret and gearset.

Postby **beavis** » Tue Dec 20, 2016 2:10 pm

thehillsarecalling wrote:It is likely that the 4 bolts that hold the shifter turret to the casing have come loose, and oil is leaking out between these two components.

I've had this issue on my 6spd. Oil puddle appeared under the car (well, on top of the flat floor), stinky trans fluid everywhere.
I muddled around under the car for a bit to find the source. When I removed the upper shifter boot up top the turret bolts were so unbelievably loose... I was surprised how bad it could get.

thehillsarecalling · Postby **thehillsarecalling** » Tue Dec 20, 2016 2:13 pm

I've had it on a few cars.

Does anyone have a factory service manual for a NB? Can you post what the manual says about tightening / using threadlocker on the bolts? I've only got a NA manual, so unfortunately doesn't cover the 6 speed.