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727 tailshaft cracked in two again. #663322 04/06/10 10:24 PM 04/06/10 10:24 PM
Joined: Oct 2004 Posts: 502 North Texas 1 1AARCUDA OP mopar
1AARCUDA OP mopar 1 Joined: Oct 2004 Posts: 502 North Texas	I have about a 2" travel on my yoke that slips inside the tailshaft, Is that enough play to keep my driveshaft from hitting my tailshaft? How much play should I have? 1970 AAR CUDA 1970 Super Bee 383 Auto 1969 Super Bee 383 4Spd 1968 Satellite 500 Stroker 1986 Shelby GLHS 1970 Coronet 500 383 Auto 1996 Indy Pace Truck 1998 Dakota R/T 408 Stroker

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663323 04/06/10 10:34 PM 04/06/10 10:34 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Is it more than 3/4" out from being bottomed... whats the rest of your set up... are you running front motor plate and mid plate with a solid trans mount... I have seen many tail shafts break from that set up... what rear suspension

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663324 04/06/10 10:34 PM 04/06/10 10:34 PM
Joined: Mar 2003 Posts: 337 the netherlands 3 383duster super street
383duster super street 3 Joined: Mar 2003 Posts: 337 the netherlands	In my opinion that is 1" travel too much, 1" travel is normal and has always worked good for me. did your tailshaft cracked with the 2" travel on the yoke? Then I think that the yoke was wobbling because it was not engaged enough on the shaft.

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663325 04/06/10 11:03 PM 04/06/10 11:03 PM
Joined: Oct 2004 Posts: 502 North Texas 1 1AARCUDA OP mopar
1AARCUDA OP mopar 1 Joined: Oct 2004 Posts: 502 North Texas	When everything is in place and my rear u joint is planted in my third member yoke without the u bolts connected, I can slide my shaft in the tail housing 2 inches til it hits the area behind the splines and bottoms out. I am running a 500 stroker with moroso solid motor mounts and stock 440 GTX leaf springs and a pinion snubber. Is that 2 inches to much play? 1970 AAR CUDA 1970 Super Bee 383 Auto 1969 Super Bee 383 4Spd 1968 Satellite 500 Stroker 1986 Shelby GLHS 1970 Coronet 500 383 Auto 1996 Indy Pace Truck 1998 Dakota R/T 408 Stroker

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663326 04/06/10 11:11 PM 04/06/10 11:11 PM
Joined: Jul 2004 Posts: 19,318 State of confusion T Thumperdart I Live Here
Thumperdart I Live Here T Joined: Jul 2004 Posts: 19,318 State of confusion	Way too much..........I shoot for no more than 3/4`s of an inch myself and that`s w/Cal-tracs leaf springs and never an issue. 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663327 04/06/10 11:14 PM 04/06/10 11:14 PM
Joined: Jul 2008 Posts: 30,460 Florida STAYcation dOoC The village idiot's idiot
dOoC The village idiot's idiot Joined: Jul 2008 Posts: 30,460 Florida STAYcation	With the DS and UJ engaged into the yoke .. how much in-and-out play is there ? ...

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663328 04/06/10 11:22 PM 04/06/10 11:22 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: When everything is in place and my rear u joint is planted in my third member yoke without the u bolts connected, I can slide my shaft in the tail housing 2 inches til it hits the area behind the splines and bottoms out. I am running a 500 stroker with moroso solid motor mounts and stock 440 GTX leaf springs and a pinion snubber. Is that 2 inches to much play? WAY too much.... even in the tranny book it says 3/4" Last edited by MR_P_BODY; 04/07/10 06:36 AM.

Re: 727 tailshaft cracked in two again. [Re: MR_P_BODY] #663329 04/06/10 11:26 PM 04/06/10 11:26 PM
Joined: Dec 2007 Posts: 10,542 BROOK PARK, OH WILD BILL Senior Member of the Junior Dragster Club
WILD BILL Senior Member of the Junior Dragster Club Joined: Dec 2007 Posts: 10,542 BROOK PARK, OH	Are you checking the travel with the rear end at ride height or with the car jacked up with the axle hanging?

Re: 727 tailshaft cracked in two again. [Re: MR_P_BODY] #663330 04/06/10 11:28 PM 04/06/10 11:28 PM
Joined: Jul 2008 Posts: 30,460 Florida STAYcation dOoC The village idiot's idiot
dOoC The village idiot's idiot Joined: Jul 2008 Posts: 30,460 Florida STAYcation	Hay P ... 3/4 of an inch ? ... WOW ... if there was any real spring or pinion-angle movement .. it could bottom out. I missed that post what you quoted. Knowing this ...I would think that there is either a bend D-shaft or the bushing IN the TS is worn-out and sloppy.

Re: 727 tailshaft cracked in two again. [Re: WILD BILL] #663331 04/06/10 11:29 PM 04/06/10 11:29 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: Are you checking the travel with the rear end at ride height or with the car jacked up with the axle hanging? Very true... with that much I sure hope its hanging, shouldnt have more than 3/4" at curb height

Re: 727 tailshaft cracked in two again. [Re: dOoC] #663332 04/06/10 11:33 PM 04/06/10 11:33 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: Hay P ... 3/4 of an inch ? ... WOW ... if there was any real spring or pinion-angle movement .. it could bottom out. I missed that post what you quoted. Knowing this ...I would think that there is either a bend D-shaft or the bushing IN the TS is worn-out and sloppy. 3/4" at curb height that number comes from the 727 trans book( I forget the author but its the one everyone uses) Last edited by MR_P_BODY; 04/07/10 06:38 AM.

Re: 727 tailshaft cracked in two again. [Re: MR_P_BODY] #663333 04/07/10 07:00 AM 04/07/10 07:00 AM
Joined: Jun 2009 Posts: 162 Greentown Indiana M moparmxz member
moparmxz member M Joined: Jun 2009 Posts: 162 Greentown Indiana	My experience has been that most broken tailshafts come from a improperly shortened driveshaft(out of balance or a phasing problem).Of course lots of things could be happening,chassis flex,improper pinion angle,trans tailshaft bushing wore out. Heck even the trans shaft could be bent.Good luck Randy Brough 1967 440 Dart S/P 6.37 106mph best eighth 3150 lbs

Re: 727 tailshaft cracked in two again. [Re: moparmxz] #663334 04/07/10 08:34 AM 04/07/10 08:34 AM
Joined: Feb 2006 Posts: 1,064 Tennessee 7 727builder super stock
727builder super stock 7 Joined: Feb 2006 Posts: 1,064 Tennessee	Stock leaf springs are too weak for the power you putting out. Has too much pinion travel and under power the pinion is moving upward till it puts the u-joint in a bind then it cracks the tailhousing. What a voice!!!! http://www.godvine.com/10-Year-Old-Boy-with-Autism-Sings-Open-the-Eyes-of-My-Heart-1041.html

Re: 727 tailshaft cracked in two again. [Re: MR_P_BODY] #663335 04/07/10 09:17 AM 04/07/10 09:17 AM
Joined: Dec 2007 Posts: 10,542 BROOK PARK, OH WILD BILL Senior Member of the Junior Dragster Club
WILD BILL Senior Member of the Junior Dragster Club Joined: Dec 2007 Posts: 10,542 BROOK PARK, OH	Quote: I forget the author but its the one everyone uses Carl Munroe

Re: 727 tailshaft cracked in two again. [Re: WILD BILL] #663336 04/07/10 09:19 AM 04/07/10 09:19 AM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Quote: Quote: I forget the author but its the one everyone uses Carl Munroe Yeah... that be him... thanks Bill

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663337 04/07/10 10:48 AM 04/07/10 10:48 AM
Joined: Oct 2004 Posts: 502 North Texas 1 1AARCUDA OP mopar
1AARCUDA OP mopar 1 Joined: Oct 2004 Posts: 502 North Texas	The car is on jackstands with the jacks on the axle tubes. taking the driveshaft to get 2" cut off new u joints and rebalance. 1970 AAR CUDA 1970 Super Bee 383 Auto 1969 Super Bee 383 4Spd 1968 Satellite 500 Stroker 1986 Shelby GLHS 1970 Coronet 500 383 Auto 1996 Indy Pace Truck 1998 Dakota R/T 408 Stroker

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663338 04/07/10 10:59 AM 04/07/10 10:59 AM
Joined: Mar 2003 Posts: 337 the netherlands 3 383duster super street
383duster super street 3 Joined: Mar 2003 Posts: 337 the netherlands	Quote: taking the driveshaft to get 2" cut off new u joints and rebalance. I think it is better too add 1" , cutting off 2" wil give you 4" endplay

Re: 727 tailshaft cracked in two again. [Re: 383duster] #663339 04/07/10 12:13 PM 04/07/10 12:13 PM
Joined: Jan 2003 Posts: 5,894 Florida Locomotion master
Locomotion master Joined: Jan 2003 Posts: 5,894 Florida	Consider all the possibilities that moparmxz mentioned. Also check the trans mount. If it has any age to it, replace it with a poly mount. I've always tried to get as much slip-spline engagement as possible. 3/4" - 1" is enough to allow enough u-joint clearance to remove the driveshaft with weight on the rear suspension or the rear end hanging.

Re: 727 tailshaft cracked in two again. [Re: 383duster] #663340 04/07/10 02:43 PM 04/07/10 02:43 PM
Joined: Jan 2003 Posts: 4,247 Newfoundland C codfish master
codfish master C Joined: Jan 2003 Posts: 4,247 Newfoundland	Quote: Quote: taking the driveshaft to get 2" cut off new u joints and rebalance. I think it is better too add 1" , cutting off 2" wil give you 4" endplay I hope he didn't leave yet. codfish

Re: 727 tailshaft cracked in two again. [Re: 1AARCUDA] #663341 04/07/10 02:56 PM 04/07/10 02:56 PM
Joined: Oct 2004 Posts: 502 North Texas 1 1AARCUDA OP mopar
1AARCUDA OP mopar 1 Joined: Oct 2004 Posts: 502 North Texas	Yes I left and I did double check and had them remove one inch only, Also After I removed my cracked housing I noticed that my shaft has some movement maybe a 1/8 inch side to side, is that normal? 1970 AAR CUDA 1970 Super Bee 383 Auto 1969 Super Bee 383 4Spd 1968 Satellite 500 Stroker 1986 Shelby GLHS 1970 Coronet 500 383 Auto 1996 Indy Pace Truck 1998 Dakota R/T 408 Stroker

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