Help - major tranmission leak by driveshaft

[1970Moparmann]

Guys, need some help please.   I will admit that I like learning, but don't know much when it comes to mechanical issues.  I just keep learning...  

Anyway, long story short, I have my sisters 70 Charger that has a fresh 727 and it's leaking like a bastard by the driveshaft connection (slip yoke).   What needs to be done?

The car was just converted to a 727 from a 833, and I'm pretty sure the same driveshaft was used-I'm checking on this.

The funny thing is I drove the car 25 miles with zero issues, and then today going to a show it started to leak on the expressway and is now leaking all the time even sitting.

Thanks.

[Fred]

I'm guessing you either need a new seal or the slip yoke is worn.

[FLG]

Could just be the seal but i had an issue with mine and needed to change the seal and the whole bushing...its not to bad just need to remove the tail shaft.

[Back N Black]

I agree rear seal, drop the driveshaft and replace, half hour job.

[1970Moparmann]

Thanks guys!   

[Just 6T9 CHGR]

Could it also be that the shaft is now too short to engage the output shaft fully?

[1970Moparmann]

Could it also be that the shaft is now too short to engage the output shaft fully?

I'll find out this weekend when I have some time to work on it. 

I'll let you guys know.

[John_Kunkel]

The rear seal is the most likely source but in some rare cases a mismatch of parts can cause a leak.

Some early slip yokes have a small hole drilled in the soft plug that seals off the rear end of the splines, this type of yoke was used with an internal seal on the output shaft. If the trans gets overhauled and the seal is omitted fluid will leak from the hole.