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Adjusting the Automatic Transmission Kick down
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KICK DOWN ADJUSTMENTS on TORQUEFLITE "cast iron"

Since I overhauled some Torqueflites I always had some problems with the "forced kick down" (or forced downshift 3-2 or 2-1 or 3-1). Generally it does not function properly and one depresses in vain on the accelerator, the car does not downshift..

VERY SIGNIFICANT: on all the "old transmissions"  (before '70) the kick down occurs only in the last 1/10 inches before the pedal goes to floor. If you accelerate hardly but without going "to the floor" you will not have a kick down !

For a few weeks I have studied well the question, send requests to the mailing lists and made various tests.

 Now I have a  correct kick down on my Imperial !! It's just a matter of adjustment but NOT AS INDICATES IN the SHOP MANUAL . Only problem, as my transmission up shifts badly  from 2 into 3 (lack of synchronization between release of  KD band and engagement of rear clutch) I have it also in kick down 3-2. Thus my trans. should re-overhauled this winter. But at least it "(forced) downshifts" now !  Problem solved (at 90 %) : bad kick down band adjustment (with manual adjustment...), I'll let know what happen on mailing list.

The various methods of the FSM are  described on the pics A-B-C-D-E  below (click to enlarge). Approximately, here what is indicated (I summarize):

• check if the accelerator pedal has a 118°  angle  to horizontal (or 115 or 114, that depends on the model or FSM)
•  Run engine until normal temperature is reached then stop. Check for choke being fully opened . Set idle to 500 rpm.
• Loosen the carburetor throttle linkage nut on the carb. rod ("B" on left pic)
• Move the rod rearward against idle stop (in trans.).
• With rod preloaded and in line, lock the adjusting nut

But this method doesn't work on my car ! If I make the FSM adjustment the transmission throttle lever can't go to "kick down" position (all the way backwards) when the accelerator pedal is floored..

I advise you to first test the FSM method and if it doesn't work (lack of KD), take a look at my method (bottom of this page)

A	B	C	D	E
'57-58-59 adjustments (shop manual)		another '59 adjustment	300C throttle linkage adjust.

Note: on all pics on this page the "throttle valve spring" has been removed for purpose of easier pics. This spring is between kick down and throttle valves , see position on pic # 1 and pic 4c.

Picture 1 : "release" position (throttle lever on "stop" adjusting bolt). The port A is by KD valve large diameter. You can seen a part of this large diameter at the left of A . The "check balls port"  has been tracked on the other valve bodies and yes it leads to check balls "1-2" and "2-3" which are in the lower valve body then to shift valves.
According to the pic, this check balls port is in relation with the "vent" port via spring and small diameter KD. valve

Click to enlarge

1	1a	1b
Valve position	1 3/4 "  (refer to pic at extreme right to know how I take measurement)		How I measure at throttle lever: between front of cable housing (at cable opening)  and larger diameter of the throttle lever

Picture 2 :  As it is with light throttle (1/4 maybe ?). The throttle lever has pushed a little the KD valve. Port A remains

2	2a	2b
Valve position		2  9/16 "

Picture 3 : You push hard on the gas pedal so throttle lever pushes on KD valve stem (you feel resistance because you must compress the valve spring). But the port A is always (the larger diameter hasn't still open the port, see pic) ... So no kick down

3	3a	3b
Valve position		3 1/4 "

Picture 4 : maximum travel of throttle lever , the KD valve is all the way in and the valve spring is completely compressed (need a lot of strength..). Now the port A is open and throttle pressure can go to the check balls and 1-2 / 2-3 shift valves. The "larger diameter" KD valve closes now the opening between "check balls port" and vent port.

this is the kick down position

4	4a	4b
Valve position		3  9/16 "

• Check , with pedal floored, that the butterflies of the carb  are fully opened and that the carb linkage is bottomed (all the way forward) . You can shorten a little the accelerator pedal rod from under the car. It's a very important step because if there's something who prevents the pedal to be floored (i.e. carpet or mat) you'll never go to KD . 118° or 115 °, don't worry, you must have a complete travel before floor.
• At trans., remove the "accelerator shaft to transmission rod assy" (cotter pin) , see pic at top of the page, and check the measurements given in pics # 1b and 4b (extreme positions).  Normally you'll find the same than mine . Anyway there's no adjustment...
• Move the throttle lever against its rear stop (KD position as in pic 4b) , have an help who floors the accelerator pedal and check if the cotter pin shaft of the rod is in line with the throttle lever mounting hole. Best is to have the rod a fraction of inch further from the throttle hole.

• If adjustment is to be made, shorten (rarely..) or lengthen the rod at locknut "A" or"A" on pic below. Yes, the manual says: the purpose of this adjustment is to allow for variations between chassis and engine assemblies (..) and should not be used for making throttle linkage adjustment. But in my case it was the only adjustment which works !  Check again the adjustment and tell to your help in car to release and floor several times the pedal. When the pedal is 95 to 100 % floored, the throttle lever must be all the way rearward. 
  After this adjustment, if the pedal is released you'll see that the throttle lever doesn't bottomed on "idle" stop (like 1b pic) but rather at an intermediate position between 1b and 2b So if you follow the FSM manual with throttle lever on "idle stop" you never go to KD position.

Now test the car ..

Our Thanks to Phil_The_Frenchie of Forward Look for providing this information.