Poor kickdown performance. Ideas?

[cruiser]

Hi All:
I have the factory original A-904 Torqueflite in my six cylinder 1974 Duster. I had the trans professionally rebuilt six years ago, and am generally satisfied with it. One problem however, is the kickdown performance. When I roll down to a near stop, still going about 5 mph after coming off highway speed, if I resume driving from 5 mph the tranny still stays in third gear some of the time. If I come to a full stop, it shifts down to first as it should, then upshifts normally. Passing kickdown performance, the 3-2 downshift when I'm passing another car, is normal.
The trans throttle linkage is properly installed and adjusted as per the FSM. I feel that when I slow down, such as making a U-turn from highway speed, I ought to get a crisp downshift to first as I start out again. This doesn't happen. I know there is an adjuster on the outside of the case. I read up on it in the FSM but can't figure out how to adjust it. Any and all help would be appreciated. Thanks!

 

[George Jets]

I would say your idle is set 100 rpm too high.

If you are idling at 850 rpm, try 750 rpm or even 650 rpm.

If it's an AC car, that is going to kick the rpms up at idle to offset the load of the AC compressor.


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[cruiser]

I would say your idle is set 100 rpm too high.

If you are idling at 850 rpm, try 750 rpm or even 650 rpm.

If it's an AC car, that is going to kick the rpms up at idle to offset the load of the AC compressor.


☆☆☆☆☆

Thanks, George. Idle is set at 750 per the sticker in the engine compartment. Not an a/c car. I gotta think it must be something with the kickdown adjuster on the side of the trans. Just not sure where to go from here.

 

[Demonic]

Do a band adjustment/check. When was the filter changed last? If you like buying tools, get a 4” liquid filled 0-300 psi gauge and some high pressure hose, and some 1/8” mpt adapters. Pressure test specs are in the FSM

 

[toolmanmike]

Part throttle kickdown? The 74 should have that.

 

[Oldmanmopar]

Part throttle valve. Transmission shops like to take them from customer transmissions to use in performance street builds. Its only three screws but cannot be forgotten accidently because a plate must be put in its place with shorter screws. Could have been taken many years ago. Or the trans is out of an older car. Easily installed most transmission sites carry them.