Another cracked tailshaft housing

[mally69]

Cracked my tailshaft housing 727. Brand new driveshaft from mancini racing. I have the slip yoke 1 inch away from bottoming out. List reasons as to why this happened.  I am using ss springs on lower setting.Not sure thay wpuld cause this.  I was having this happen before due to driveshaft being to long and binding up. But its been changed with all new stuff.

[gtx6970]

An inch doesn't sound right.
I went thru this a couple years ago and best I remember you measure it about an inch off the rear balloon seal which equates to about 1.5" off bottom.

The OEM parts book lists the correct length ( length varies with which transmission  and rear axle choice )

[mally69]

Ill go double check just to make sure

[Birdflu]

We've been measuring and installing shafts in cars for years by installing the yoke, bottom it out in the transmission and pulling it out an inch. As long as you're doing this with the car on the ground (suspension loaded the same way it is driving down the road), you'll have more than enough 'travel' in your drive line. These cars don't 'push' or 'pull' on the yoke the way a lifted short wheel base Jeep does when it's crawling the rocks out in Moab. Some guys have mistakenly measured for their drive shafts with the rear ends hanging while the car is on a hoist or used a floor jack under the body so they could squeeze under the car. Both of those techniques will give you a false measurement.
Is it possible the main shaft in your Torqueflite is bent? Easy to check with a bare slip yoke and dial indicator.

[mally69]

With weight on tires i have 1 full inch. I will drop it all tomorrow and set a dial indicator to check the main shaft.  That could be possible due it breaking before a few times.

[c00nhunterjoe]

Is the crossmember in a bind?

[John_Kunkel]

Where is the housing cracking? If the problem persists you might consider a HD truck housing pictured at the top in the pic below. Problem is they have no provisions for a console shifter.

[mally69]

Everything bolted right up.  Breaks 6inches back from the seal

[mally69]

Crawled back under looked really close with a brighter light , its not cracked, i saw the casting mark and appeared like a crack. Shaft isnt bent. BUT i found my poly locking engine mounts both pull apart. Im assuming this is whats causing my wierd vibration.

[Birdflu]

Ahhh...engine mounts could have also been a factor in your first failure...

[mally69]

They were the locking ones from 440source. Divers side is def broke

[TexasStroker]

If you aren't running a torque strap it would be a cheap, worthwhile addition. 

[firefighter3931]

They were the locking ones from 440source. Divers side is def broke

Make your own bomb-proof mounts :

http://www.dodgecharger.com/forum/index.php/topic,13216.0.html



Ron

[BLK 68 R/T]

440 source website says they are lifetime guarantee as long as you own the car, assuming they are the Dynatech locking mounts?