Leak from 6 speed trans - From Where???
 

My trans is leaking from the area somewhere under the reverse backup sensor. Replaced the sensor (which was leaking too) but I am still dripping from somewhere.

The oil is collecting in the red circled area (lowest point so that’s kind of obvious). I’ve semi-cleaned up the area but the only place that’s wet is that bottom area itself. The bolts circled in orange are also wet but I doubt that is where the leak is coming from.

Anyone have any idea where this could be coming from? I’ve had the trans out 4 times over the past year so I’m praying it isn’t the seam.


https://cimg7.ibsrv.net/gimg/www.mia...36b886afa.jpeg

More than likely the seam. It's happened to both 6 speeds I've put in my car. Pull trans, take tail shaft housing off, re-RTV, re-install.

So I have located the leak. It is on the passenger side of the trans about halfway up right along the seam where the tail shaft and intermediate housing meet. Is there a vent here or something?

I really don’t think this started until the last time I refilled the trans. Is it possible I overfilled and it is leaking from a weep hole? I tried to shove some ultra-black rtv in that area to stop it but that seems to have done absolutely nothing.

You can see in the picture where I put the RTV, which is where the leak is


https://cimg0.ibsrv.net/gimg/www.mia...a5e28472f.jpeg

I discovered a drop of fresh oil hanging off the case at that same exact location on my 6 speed over the weekend. I also cleaned everything and am hoping to find the source. Is fluorescent tracer dye an option with a manual transmission? I've never tried it.

That orange RTV from the factory never fails to freak me out on 6 speeds, it always feels like someone else has been in there before I got it but every one I've ever seen has it.

Yeah it freaked me out for a second too. Apparently this isn’t a common problem, but I don’t see any way of fixing it without taking the whole thing apart. And if I end up having to do that, I’m just going to buy a new restored trans. Everything else on this car has worked fine but this trans has given me so many problems. Hoping I can just keep adding RTV until something stops lol

The leak there is incredibly common. But luckily easy to fix as others have said.

With mine I'm not sure it's enough to really worry about at the moment, I'm just going to top it up and send it. I'll deal with it the next time I've got the trans out, it's not like I'm staring at a puddle of gear oil in the driveway.

Anyone ever fixed this without pulling the entire trans?

No.

Im so happy i resealed my tailshaft
the first time i opened my 6 speed...

Pulling the tailhousing off the 6 speed sounds like a really good way for me to fall down the "while I'm in here..." rabbit hole of seals and bearings. :giggle:

What prevents that housing from being pulled with the trans still attached to the engine?

Probably nothing that I can think of. Accessibility to all the bolts might be an issue though.

Disassembly/Reassembling on your back with a trans tunnel in the way, unable to swing a hammer, holding in detent springs and balls, and aligning shafts
properly, all to save 40 min sounds like a really bad idea.

It’s not 40 mins for me. Removing the trans requires removing exhaust, turbo, ppf, etc.

Sorry, 45 min? Why does your turbo have to come out. That’s weird.

Exhaust is in the way of trans, so it has to go. Exhaust/downpipe is connected to the turbo, and is pretty much impossible to remove without removing entire turbo itself. Which then means disconnecting coolant and oil lines, etc. Unless someone can offer a better way, that’s the only way I can get the trans out that I know of.

Well, this sounds like a fucking nightmare. Is this process documented anywhere?

short of being fiddly, removing the tailhousing shouldn't be that hard.

Attachment 227179
this is the earlier type (~2001?) and the later type has an 'indent-plunger' mounted on the exhaust side of the selector-rod (at the top, ~ 1/4 of the way foreward from the gearstick, secured with an allen-headded bolt.)

Attachment 227180
later type, indent-plunger sticking out the side in front of the gearshift.

Attachment 227181
easy enough.

Attachment 227182
top photo is worth note, dont refit without this as you'll swear a little:giggle:

I found the Mazda gearbox manual on the internot somewhere as a pdf, will see if I can find the link...

Rich.

Now that I'm thinking about it, I think someone gave me a digital copy of the 6 speed shop manual, might cover the 5 speed as well. I'll root around when I get home and take a look