56 Dynaflow

[Guest Koala]

On random occasions my 56 Dynaflow does not select forward or reverse gears correctly and gives off a whirring sound and slips in the selected gear with only slight drive to the wheels. If I then move the gear selector through the gears it will select gears correctly and works just fine. Mostly it happens after the car has been parked and is cold but can happen when hot. I guess it is something to do with the valve that switches from front to rear pumps. According to the book the front pump can lose its prime and cause a delayed gear selection but I don't think this is my problem as it can happen at any time not just when first starting.

Can anyone provide any advice before I start pulling it apart.???

Thank you in advance.

Koala

Edited December 16, 2010 by Koala (see edit history)

[MrEarl]

My first check would be engine and transmission mounts. Either one of the being broken can cause the symptoms you speak of. Especially in reverse

[Guest NikeAjax]

I concur! Sometimes you think it's in reverse, but in reality, it's in low: I killed a fence about 20 years ago like that: uff da! It being a real car, there was no damage to the car, but that fence was toast.

Jaybird

[stealthbob]

Just to be clear in my mind how this all works....

If the mounts are bad that changes the position on the transmission thus the linkage to it?

[Guest Koala]

I am aware of that particular problem with the mounts and have previously replaced the mounts and the thrust pad as well as checking the linkage adjustment.

Seems more like a hydraulic valve problem to me.

Koala

[old-tank]

Koala

Check the pressures as outlined in the service manual, read the troubleshooting procedures and study the hydraulic circuits. The valve body can be removed, but other than the mounting gasket and two servos not much can go wrong there.

Willie