where to get or modify kickdown switch
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
Likes: 0
From: High Desert California
where to get or modify kickdown switch
Where can I get a kickdown switch for a TH400? Are there wiring modifications using stock pedal. This is on a 78 T/A wherein we changed the TH350 to a 400.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
There is a kickdown switch in the car (either on the accel. linkage or on the carb..depending on year); but there is also a solenoid switch inside the THM400. It mounts to the valve body pad and is activated by the car switch. Both switches are needed--one to supply 12v. and one to cause the downshift--and both can go bad.
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
There are a couple good ways to do this. Lokar makes a TH400 kickdown that has one end attached to the throttle bracket that allows you to mount the electric box where it's convenient for you. You can also still buy the factory carb switch and bracket that mounts on the carb. You could also run your own switch on your own bracket. It's nothing complex. Just a contact switch.
NCM Grand Opening Veteran
Joined: Sep 2005
Posts: 20,979
Likes: 384
From: South of giving a damn
St. Jude Donor '11, '17
Go get one for an 81 Silverado. They are all the same. The bracket is already in place & the switch fits right on. You will need to take 12v to the switch & then from the switch to the blade on the drivers side of the tranny. The way to check the tranny is to take a hot wire & touch the tranny connector, if you hear the solenoid click then you are probably OK. Ground is through the tranny case.
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That's what you need to do.
Thread Starter
Burning Brakes
Joined: Feb 2006
Posts: 841
Likes: 0
From: High Desert California
Go get one for an 81 Silverado. They are all the same. The bracket is already in place & the switch fits right on. You will need to take 12v to the switch & then from the switch to the blade on the drivers side of the tranny. The way to check the tranny is to take a hot wire & touch the tranny connector, if you hear the solenoid click then you are probably OK. Ground is through the tranny case.
. All I have to do is google search how an 81 siverado looks like and my son and I can take a trip down the local junkyard. Thank you.......
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