727 transmission dementions

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Andrew vanman87

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The transmission tail shafts Short in my 71 Newport? I was under the impression they were the same size... I went to drop in my drive shaft and it wouldn't fit ( new one in Orange) drive shaft too long...

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Your 'Guide' to the 727/904 transmission

Often I or anyone for that matter asks to find out what type of transmission they have in their old mopar. There are hundreds, if not a thousand, of threads on this website identifying, discussing or assisting with this process, troubleshooting or repair. Because of this large number of...
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I know that there were some shorter tail shafts with 727s. .. however I'm not sure that's what's going on yet...
The full story is my 71 Newport 727 383 car was purchased with a transmission that had tons of problems no third gear lots of noise pump always winding... So I purchased this other one the one in Orange.. when I put it on there I noticed that there was drive shaft fitment issues... I may want to check to see if the drive shaft is the correct length... It looks like a newer drive shaft certainly doesn't look original... It's possible the shaft was too long to begin with.. and the transmission that was in the car was already making tons of noise... Black fluid
 
But the last photo I posted was from the transmission I pulled out of my Newport 383 the orange one is the new transmission I got
 
In post 1 your are measuring the orange from it's left side. In post 2 it looks like you are measuring the old one from on top. Please double check both transmissions and measure from the same spots, probably left side since I assume the orange one is still in.

I suspect they are much closer than the previously measurements indicate. If the transmission bolted to the engine and the transmission mount will line up I expect them to be the same length. I am not familiar with any different in the lengths of the long style output and housing, and your pictures clearly show they are both 727 transmissions. I am wondering, if the lengths are in fact close, that the slip yoke is getting stuck in the tailhousing bushing or on the splines of the output shaft itself. I am interested in seeing where this all ends up.
 
I'm going to start working on it again probably Monday or Tuesday I'll let you know what it was... Other odd thing is at the drive shaft from the center u-joint to center a u-joint 59 in... Seems a bit long... At least according to the manual that I read 4cbodies drive shaft length
 
I was under the impression that 727 long shafts had ONLY ONE shaft length?????

There are short shaft--with no slip yoke ones out of motor homes. They are obviously short, have no slip yoke, and the yoke bolts to the end of the output shaft. You must then have a slip joint built into the drive shaft. Those are NOT used in passenger cars unless someone adapted one

Looks to me like what you pictured are two of the same transmissions.

tf_length.jpg

Below, motorhome TF
motorhomeTF.jpg
 
There's only one length of big block 727 that I know of. Drag that orange 727 off the mat, over onto the tile. Line the front bottom edge of the bellhousing up exactly with the tile seam. Go to the other end of the transmission and use a straight edge like a framing square to line up with the end of the tailshaft where the splines are. You will need to move the rubber boot back a little and don't move the transmission on the floor. Mark with a pencil where the straight edge sits on the floor right below the end of the shaft. Drag that 727 out of the way and drag the other one over and line it up same way at bottom of bellhousing. The tailshaft should line up with your pencil mark on the floor. I'm thinking the driveshaft is the wrong one unless it was in the car and you drove it before.
 
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