Not a good start to my season...

[Roughbird72]

Made my first pass, during shutdown I had a severe vibration in the drivetrain and broke the output shaft housing on my 727. I thought maybe I didn't get all the u joint retainers in good and a u joint moved, but that's not the case. The only time I've had this happen before is when a u joint went to ****. Other than a driveshaft that could have issues, what else may have caused this???

 

[malex]

Made my first pass, during shutdown I had a severe vibration in the drivetrain and broke the output shaft housing on my 727. I thought maybe I didn't get all the u joint retainers in good and a u joint moved, but that's not the case. The only time I've had this happen before is when a u joint went to ****. Other than a driveshaft that could have issues, what else may have caused this???

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Sorry to hear of the bad luck. If your driveshaft is good did you spin the trans and diff?

 

[artr8]

Check the condition of your rear tranny mount.

 

[Roughbird72]

The trans mount is fine and nothing else is loose or broken that I can see. However, i decided to check the driveshaft runout.
4" from center of the rear u joint .012"
4" from center of the front u joint .044"
The middle of the slip yoke barrel .012" ... easy to check since a foot of the housing is missing.lol

 

[Wookie316]

I broke the tail shaft housing last year. It was from a diff explosion. I pulled and inspected. Good thing. The sprag was starting to roll over.
If you didn’t over speed it, you at probably ok just replacing the tail shaft. Only you know what exactly happened to determine how deep you go.

 

[Roughbird72]

I'll pull the trans just to be on the safe side.

 

[dvw]

How far can the shaft be pushed forward before it bottoms in the trans? If its to long it'll bust it.
Doug

 

[Roughbird72]

How far can the shaft be pushed forward before it bottoms in the trans? If its to long it'll bust it.
Doug

1 1/8"

 

[dvw]

1 1/8"

That's plenty.
Doug

 

[Roughbird72]

That's plenty.
Doug

Yeh, going to have a new shaft made just a little longer and try to get that to 7/8-15/16 ... and check the run out before making a pass.

 

[AndersonTommy]

You need 3/4" to go into the transmission to be correct. I'd be checking the ring and pinion for broken teeth. Also pull the transmission. I'm sure it is damaged internally.

 

[bigbluedodge]

I broke 2 tailshafts before I figured out that my pinion angle was WRONG. I had changed the rear suspension around without checking.........

bry