727 Torqueflite - 64 Sport Fury 426 Street Wedge

[Van Stahr]

This one is a little weird and I have tried a few things from the forums but nothing yet.

727 3-speed auto oil is full. Kickdown is connected and checked the adjustment. I am going to reset the control cable adjusting wheel per the manual this weekend.

When stopped, if I put it in Drive I just hear a faint whine but the car doesn't move. Same thing in Second. Drop it in First and she goes, then shift to second and shifts smooth, then on to Drive and it shifts to Third nice. Stop at a light and no go. Have to shift to First and basically drive it as a 3-speed. I don't mind the shifting, but I am concerned that if something is wrong with the transmission I might be making it worse driving it.

Any ideas?

 

[VANDAN]

Maybe some more Details on the Transmission, and install. Original to car, or different Year / Model. Any Mods, Pan on it, Deeper Pan ? Has been Running ? A Lot of Possibilities ?

 

[Nate S]

Definitely some questions. Did it work before then stop? New install? Sort of matches a bad cable adjustment. If the manual valve is borderline neutral / drive it could do something like this. Looking at the schematic that’s the only thing I see that might keep fluid pressure from the rear clutch (or anything else for that matter).

If it worked then stopped working could be the governor is stuck open and you’re trying to start in 3rd. Unlikely in a ‘64 tranny though because that’s tied to the rear pump.

Tell us more.

 

[w.Hudson]

The low sprag is broken. Damage is done but you are circulating metal debris anytime it is running.

The clue that you gave is that it will take off in first when you put the shifter in 1st.
Normally the sprag would hold the reverse drum in first.
The low band comes on to hold the the drum in manual first.
To achieve first gear you need the sprag to hold the drum and the forward clutches on.

 

[Nate S]

The low sprag is broken. Damage is done but you are circulating metal debris anytime it is running.

The clue that you gave is that it will take off in first when you put the shifter in 1st.
Normally the sprag would hold the reverse drum in first.
The low band comes on to hold the the drum in manual first.
To achieve first gear you need the sprag to hold the drum and the forward clutches on.

Wow, you’re good. That makes complete sense. Didn’t even think of that.

 

[493 Mike]

This is a timely subject for me as I am installing a A&A super sprag currently! By the way the A&A sprag can be used to save a damaged (blown sprag) case if needed.
Mike

 

[Van Stahr]

The low sprag is broken. Damage is done but you are circulating metal debris anytime it is running.

The clue that you gave is that it will take off in first when you put the shifter in 1st.
Normally the sprag would hold the reverse drum in first.
The low band comes on to hold the the drum in manual first.
To achieve first gear you need the sprag to hold the drum and the forward clutches on.

Thanks for the info.