Leaky front seal on M5OD

[Evan]

More likely the REAR bearing retainer is bad and that is allowing
the mainshaft and input shaft to walk back and firth in a display
of grossly excess endplay and that has toasted the seal.

AD

Last time I had it out there was quite a bit of play in the input shaft.

The tranny makes kind of a "chugging" sound, especially in fifth. It's louder at low RPM and under load. The leak is quite bad now. Drove it to work today and there was a line of fluid leading to my parking spot.

Think I may have found a replacement I can swap in. Then I'll rebuild the current one at my leisure and post a nice writeup on TRS.

Anyway, I agree with you on the retainer. There is no bad bearing noice from the tranny...no popping, whining, or squealing. It's always been lubricated well.

 

[mjonesjr]

My M50D is making a grinding noise in 5th gear when I let off the throttle. I can't figure it out because it is only in 5th gear and when I am coasting.

 

[Evan]

Got an M5OD off a 2.9 for $150.

Looks to be in good shape with no leaks. Guy said it worked perfect when pulled.

 

[AllanD]

Last time I had it out there was quite a bit of play in the input shaft.

The tranny makes kind of a "chugging" sound, especially in fifth. It's louder at low RPM and under load. The leak is quite bad now. Drove it to work today and there was a line of fluid leading to my parking spot.

Think I may have found a replacement I can swap in. Then I'll rebuild the current one at my leisure and post a nice writeup on TRS.

Anyway, I agree with you on the retainer. There is no bad bearing noice from the tranny...no popping, whining, or squealing. It's always been lubricated well.

Input shaft play implies mainshaft end play because the Mazda
is basically two tapered rollers in opposition.

And the "weak link" in the system is the rear bearing retainer.

AD

 

[mjonesjr]

Got an M5OD off a 2.9 for $150.

Looks to be in good shape with no leaks. Guy said it worked perfect when pulled.

I wish you were closer, I would buy it off you in a heart beat!

 

[sfwjesse]

I just got an M5OD for my dads rig for 140 with 130k on it. Always a gamble taking peoples word for it but ill cross my fingers. No leaks except a little bit on the shift rail plugs. At least the slave isn't melted to the housing like my dads! lol

 

[Mac]

Transmissions and differentials I don't play with. I've had Paul's Transmissions (used to be at least) down by Belts do the work on mine. Got a couple of the Ford shop manuals if you want to try it your self. Got to get one running good so you can put that KB on the Cobra.
Dave - Amherst

 

[Evan]

Got the Craigslist M5OD swapped in. Had the top cover off and everything inside looked good. There was a little play in the front shaft but not nearly as much as the bad one. Drove it a bit today and everything seems to be good.

Man, I hate taking trannys out. So much work! Especially with a doubler, having the extra skidplate, linkage, etc. Took me 12 hours.

The nice thing is that the tranny I got came from a 2.9, so it's got a lower first gear ratio than my 4.0L M5OD had.

 

[mjonesjr]

Got the Craigslist M5OD swapped in. Had the top cover off and everything inside looked good. There was a little play in the front shaft but not nearly as much as the bad one. Drove it a bit today and everything seems to be good.

Glad you got her swapped.

Man, I hate taking trannys out. So much work! Especially with a doubler, having the extra skidplate, linkage, etc. Took me 12 hours.

You must have been working alone.

The nice thing is that the tranny I got came from a 2.9, so it's got a lower first gear ratio than my 4.0L M5OD had.

That is why I wish I could find a 2.9 M50D.

 

[Evan]

You must have been working alone.

Yep. Also swapped my top plate from my old tranny into this new one so that took some time. Did that because the old one had the metal "freeze plugs" on the shiftrail ends and the new one had the leaky rubber ones.