[krunch007]

Hey guys,
Bought a truck that has a TH400 trans. The kickdown switch was not connected. I do not know for how long. But I put a Lokar kickdown switch on it.
When I took it out for a test drive the kickdown worked but then it would not shift back up to 3rd? It was like that gear just disappeared.
My guess is that the solenoid is now stuck?????
I disconnected the solenoid from the kickdown swicth thinking it might simply go back to the former version of itself but no change. Can these solenoids stick even with the pwer disconnected? Any and all help appreciated.

[Crosley]

if the electric kick down solenoid was open & blowing off fluid, the 1-2 shift would be late.

is the 1 - 2 shift late or the 1-2 shift is at normal road speed under lite throttle?

[krunch007]

Originally Posted by Crosley

if the electric kick down solenoid was open & blowing off fluid, the 1-2 shift would be late.

is the 1 - 2 shift late or the 1-2 shift is at normal road speed under lite throttle?

The 1-2 are seeming to come in later. And basically 3 in non existent. At least up to about 4000 rpm.
I did just run a wire direct from the battery and touch the terminal a few times and no click at all. So it may be just stuck in the forward position.

Basically I did the kickdown switch installation and just ran it so that is the only thing that changed. I literally had it out a car show 2 hours prior to installing the kickdown switch.

Is there anything other than the solenoid being bad that can cause this? Just so I am not replacing a solenoid only to have the same problem later down the road.
Figuring that if I have to change the solenoid that I might as well chnage the filter and fluid too.

[Crosley]

Originally Posted by krunch007

The 1-2 are seeming to come in later. And basically 3 in non existent. At least up to about 4000 rpm.
I did just run a wire direct from the battery and touch the terminal a few times and no click at all. So it may be just stuck in the forward position.

Basically I did the kickdown switch installation and just ran it so that is the only thing that changed. I literally had it out a car show 2 hours prior to installing the kickdown switch.

Is there anything other than the solenoid being bad that can cause this? Just so I am not replacing a solenoid only to have the same problem later down the road.
Figuring that if I have to change the solenoid that I might as well chnage the filter and fluid too.

there is only the one solenoid in your trans. Earlier T-400 had 2 solenoids, one for a switch pitch converter control, the other for kick down. Not a common deal for switch pitch converter.

The kick down solenoid affects both shifts : 1 - 2 and 2 - 3 depending on road speed, rpm , ect

Replace the solenoid and a road test will give the results.

Check pan for debris , always a good idea to rip open the filter and check for debris that is sucked into the filter media