Leaky front seal on M5OD

[Evan]

Last night there was a puddle of ATF on the ground under my truck. The source was the bellhousing. It looks like my input seal is going bad on my M5OD. Couple Questions:

If a bad input bearing ruined the seal, where can I buy a replacement bearing? I found the seal at Autozone for $10 but I have not located the bearing.

How quickly do these usually go downhill? Right now the leak is not too bad...

Is the any short term fix, like ATF stop leak?

 

[mjonesjr]

You might have to get a complete bearing kit for the transmission. I think you have to take it all down to replace the front one anyway, why not do them all?

 

[Evan]

You might have to get a complete bearing kit for the transmission. I think you have to take it all down to replace the front one anyway, why not do them all?

I don't feel comfortable completely tearing apart an M5OD. What does a rebuild cost these days, if I supply the kit?

 

[mjonesjr]

I got quoted $800 from a local shop.

 

[Evan]

I think this kit will fix my problem:

http://cgi.ebay.com/ebaymotors/M5R1...005QQitemZ150336699952QQrdZ1QQsspagenameZWD1V

But you think I have to tear apart the whole tranny to replace that stuff?

 

[mjonesjr]

Yup, you have to take it all the way apart to install those parts...

I have been debating doing this to my M50D in the BII. I also want to do all the bearings.

 

[Combs Customs]

From all the stuff i've seen you do, tearing apart an M5OD should be a walk in the park for you. The hardest part is getting the big hex nut off the back of the output shaft. When my bearings show up, im going to be reassembling a 2wd one myself.

 

[AllanD]

Others will testify to this but it typically takes me 35-40minutes to completely disassemble one.

I've done it before... and I have the proper tools.

Putting one back together?

On a good day? 3-4hours.
I tend to be very methodical.

I've never seen a bad input seal caused by a bad inut bearing.

For that matter I've seen input bearings SURVIVE the teeth being melted completely
off the input gear.

Frankly I doubt the inut bearing is bad.

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

 

[trail B2]

Just put A input shaft in one last week . I'm handy but not A mechanic take your time and get A good book I had an original service manual

 

[rboyer]

Just to add, that kit that's on ebay that you were asking about does not include the input bearing anyway.

 

[rboyer]

Actually it says the "kit" handles everything minus the input and clusters but then goes on to say that it includes the input bearing but I don't see one in the picture.

 

[sfwjesse]

Check the level every now and then with your finger. My bought one with a leak there and it only had 1 qt in it........it had gotten so hot the plastic on the slave cylinder melted to the aluminum behind it.

 

[Evan]

How easy is it to swap a 4x4 tail housing onto a 2wd tranny?

 

[cocoasranger]

The bearing number 30207/80 on the bearing box in the photo is the number of the input bearing for a M5OD R-1 trans. fwiw.

 

[mjonesjr]

How easy is it to swap a 4x4 tail housing onto a 2wd tranny?

Tail housing is easy, but you also have to swap in the tail shaft which requires almost a complete tear down.