[Not A T 25]

All was going good with my rod project the new 700R4 was finally set up working good with a few short 20 mile trips on it the only issue was the addition of a transmission cooler and the shifter seemed to shake too much at certain speeds normally around 60 Mph so I put it up on the jack stands installed the new heat sink cooler and was checking for something loose on the shifter and found the transmission mount bolts loose. The transmission mount is the only thing not new so I orderd a new one today thinking that might be the culprit but happened to shake the front yoke and noticed some play so I pulled the drive shaft to check and found the play is in the tail shaft is this normal the reason I ask is the TH350 I pulled out has about the same if not more or do I have an drive line alignment issue the 350 trans has about 40,000 miles on it. I hope I am just being overly cautious and this is normal?

[Jmark]

I don't recall ever seeing a spec for the yoke to tail housing clearance, but it should be fairly tight, maybe a few thousands. With the yoke out, the output shaft will wiggle, but what you need to check is with the yoke installed. Might be time for a new tail housing bushing.

Mark

[Not A T 25]

Originally Posted by Jmark

I don't recall ever seeing a spec for the yoke to tail housing clearance, but it should be fairly tight, maybe a few thousands. With the yoke out, the output shaft will wiggle, but what you need to check is with the yoke installed. Might be time for a new tail housing bushing.

Mark

Well I see about the same movement with the yoke in this was a rebuilt Mad Dog transmission could the yoke on the drive shaft be worn instead? any ideas on what or how to check

[cboy]

If the shaft moves with the yoke installed I'm surprised you are not getting a lot of oil dripping out the end of the tailshaft. If it's anything like my C-6 there is a bushing around the yoke and then a seal out at the end of the shaft. Sounds to me like you may have to replace the bushing. As Jmark noted, the tail shaft will wiggle a bit with the yoke removed but when the yoke is installed it should fit snug inside the bushing.

[Jmark]

Its possible that the yoke is worn. Guess you'd need to find a new one and mic it and compare to yours.

[Not A T 25]

Originally Posted by Not A T 25

All was going good with my rod project the new 700R4 was finally set up working good with a few short 20 mile trips on it the only issue was the addition of a transmission cooler and the shifter seemed to shake too much at certain speeds normally around 60 Mph so I put it up on the jack stands installed the new heat sink cooler and was checking for something loose on the shifter and found the transmission mount bolts loose. The transmission mount is the only thing not new so I ordered a new one today thinking that might be the culprit but happened to shake the front yoke and noticed some play so I pulled the drive shaft to check and found the play is in the tail shaft is this normal the reason I ask is the TH350 I pulled out has about the same if not more or do I have an drive line alignment issue the 350 trans has about 40,000 miles on it. I hope I am just being overly cautious and this is normal?

Does anyone have an exploded view of the Tail housing on the 700R4 I am trying to locate a bushing and new Front drive shaft sliding yoke.

[Jmark]

the bushing can be had, often times for free, at any trans shop. You might also have them install it and the seal. The bushing needs a special remover to get it out, unless you pull the tail housing (4 bolts) and pound it out that way. On the yoke, you could try mikeing it at the very end and then where the bushing rides and note the difference in diameter. Personally, i've never seen one wear bad enough to cause a problem, unless it has a million miles on it.

[Not A T 25]

Originally Posted by Jmark

the bushing can be had, often times for free, at any trans shop. You might also have them install it and the seal. The bushing needs a special remover to get it out, unless you pull the tail housing (4 bolts) and pound it out that way. On the yoke, you could try miking it at the very end and then where the bushing rides and note the difference in diameter. Personally, i've never seen one wear bad enough to cause a problem, unless it has a million miles on it.

Well I live in the middle of no where Midwest so will have to do it myself like most other things hopefully the local NAPA can get the bushing and seal I contacted MadDog about the problem but no reply so far!

[Not A T 25]

Originally Posted by Jmark

the bushing can be had, often times for free, at any trans shop. You might also have them install it and the seal. The bushing needs a special remover to get it out, unless you pull the tail housing (4 bolts) and pound it out that way. On the yoke, you could try mikeing it at the very end and then where the bushing rides and note the difference in diameter. Personally, i've never seen one wear bad enough to cause a problem, unless it has a million miles on it.

After closer inspection of the splined yoke and trying a new tailshaft bushing on it I think this could be the exception there appears to be several steps in the OD stepping down in diameter to the end may have been turned at some time. Does anyone know the stock OD of the splined yoke on a GM automatic transmission.

[68NovaSS]

A 27 spline TCI slip yoke for the 700R4 is 1.5". Part #967300.

http://www.tciauto.com/yokes_u-joints.htm