'06 Mazda Tribute gearbox

Have a 5 speed manual transaxle. Have seepage from drainhole on gearbox. Anybody know what that indicates? Also, any recommendations on repair and cost?

Did you have the transaxle drained and filled recently? If so it probably means that the crush washer was either left off or re-used. Or maybe the drain plug was not tightened sufficiently.

I agree with PvtPublic.
The only likely causes are a drain plug that was not properly tightened, or failure to replace the crush washer.

“Quick” oil change places rarely–if ever–bother to replace crush washers when they change motor oil and transmission fluid, which is one of the many reasons why they tend to destroy engines, transmissions, differentials, and brake hydraulic systems on a regular basis.

Was this vehicle recently “serviced” by a quick lube joint?

Actually, the drainhole I speak of is entirely different from the transaxle’s hole with drainplug. It’s just a small opening on the gearbox side just as it meets the engine. It’s almost as if it was engineered so. The seepage is a black drop every so often, very viscous, and almost tarlike.

This sounds like a vent hole. It prevents the transaxle from pressurizing as it heats up from use. This prevents seal blowouts. A periodic drop or two may just be normal. The black tar may indicate a lack of service. Has the transaxle ever been serviced? I believe your model uses ATF and should be changed every 5 years or 60,000 miles. There is no filter, so it should be a quick drain and fill.

Could be the front seal on the transaxle or the rear seal on the engine.

I’m suspecting a seal since the drops started last week and the garage floor gets a daily drop overnight. The transaxle has not been serviced but 75-90W gear oil is recommended every 30K. Also, suspecting transaxle seal since seeping vent is on its side as it meets engine. Sounds like major surgery. Any ballpark figures on repair cost?

The car is 8 years old. How many miles has it been on the original gear lube? If 30k is the recommended service interval, then about 3 years is the time interval. It’s a manual, so an input shaft seal can be serviced when the clutch is changed out rather simply. With this much time on it, I would not pull out the transmission without changing the clutch. Just asking to do the job twice.

Yes, it’s behind more like 4 services. Your advice is mechanical wisdom with vision. It also gives me an idea of cost. Appreciate it, BustedKnuckles.

PvtPublic, thank you for your last insight. Attacked leak with a no leak additive in the gearbox to no effect. Then, tried a no leak additive for the rear main seal. That initially slowed the leak and after a week, there is no sign of one. I know it’s only a temporary suspension of the inevitable but in the meantime, I’m leak free.

         "I'm suspecting a seal since the drops started last week and the garage 
                                    floor gets a daily drop overnight."

With a 10 year old car, a drop a day is not anything I’d worry about.
If the leak restarts I would just put down an old piece of cardboard where you park to keep the floor from staining.
If the leak gets to where you have a small puddle every night…then I’d have it fixed. Maybe before that you will need a new clutch and you can have the seal replaced then.

Yosemite