In Drive......wont move!

[451Coronet]

First off thanks to all those that helped with my last issue. Turned out to be a simple fast idle screw adjustment. Wasn't on idle circuit.

Now im having transmission issues.

Same car. 1969 Coronet. 451 Stroker. 727. 3.91 SG

Car doesn't move in D but Reverse works great.

It actually happened several weeks ago, but just now got around to pulling trans. Anyways I was out cruising, when after a slightly spirited take off from a stop, I came to a light, stopped, light changed, car wouldn't move. Managed to limp it home. Allowing the car to idle in gear would roll fwd and eventually gain enough momentum to use the gas to get to cruising speed. But giving gas while at rest.....doesn't move.

After I got it home...putting it in N and revving it then popping into D seemed to help. I figured serious internal trans issue, a pump or some other such witchcraft which makes these things work. Picked up another trans cheap Ans was simply going to swap them.

Still would like to know the problem tho. Is my bad pump theory sound on track? Anything I should check on the 'new' trans before installing?

As always any help is greatly appreciated.

 

[dvw]

Rear clutch is either slipping or not being commanded by the valve body. Pull the pan, heavy debris means the clutch is toast. The rear clutch is applied in all forward gears but not reverse.
Doug

 

[texas69bee]

You may have a torque converter seal issue. I had the same problem with a 98 pickup. After it sat for a while, all fluid in converter would leak out. I would have to rev the motor then slam it into drive to get it to go. I noticed you were already out driving but I thought I'd share it with ya for something to check. Also driving in reverse helped it fill quicker. I tried the trans flush from a professional shop and it made this problem worse.

 

[Photon440]

If your sprag is shot, it would still move with the selector in 1 but not D. Have you tried that?

 

[451Coronet]

Tried in all foward gears....no movement.
Also dropped pan and there was some friction material coating bottom of the pan. Went ahead and changed fluid and filter. No metal shavings or chunks

- - - Updated - - -

No leaking fluid. Also converter still had fluid.

Debating on whethervor not taking the chance to reuse the converter.

 

[mopar 3 B]

Rear clutch must operate with all forward gears. If your convertor is stock exchange it if not find a transmission shop and have it flushed and checked.

 

[dryheat]

Do you have the kick down linkage installed?

 

[dvw]

If the converter was broke it wouldn't back up. If the sprag was broke it would only loose 1st gear in drive. Pull the trans out and pull it apart. You can have a 727 gutted in 10 minutes. Pull the pan and valve body. Tighten the outer band adjusting nut snug. Remove the pump bolts. Pick the trans up and tap the bell housing end on the ground,the pump will fall out. Loosen the band anchor, remove the band and strut. Pull the input shaft up and out. You're there. Now remove the snap rings and inspect the clutch packs. The rear one with the shaft attached will be toast.
Doug

 

[451Coronet]

Rear clutch was gone...

Went ahead and installed replacement trans and driving it, might have a go at rebuilding the old one. Replacement has part throttle kickdown which I don't like

 

[69a100]

Rear clutch was gone...

Replacement has part throttle kickdown which I don't like

If your old tranny didn't have that, just swap the in the old valve body.

 

[Sixpactogo]

I am thinking your kick down linkage is not corrrectly adjusted. That may have been the culprit with your other transmission. If you have the FSM, it will tell you how to adjust the kick down linkage. No kick down linkage will eat a 727 in short order.