Th400 kickdown switch

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Hamgrease

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Hey everyone, I have a 85 C10 that was originally a 6.2 diesel/700r4 truck. It now has a 454/400. I’ve installed the kickdown switch solenoid on the petal bracket and made my own harness, it works I’ve tested it. My question is are the accelerator petals different for the TH400 from other transmissions ? My petal doesn’t reach far enough to engage the switch. I’m considering fabricating and welding an adapter rod to it for engagement of the switch.
 
Rickf

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Flower power.
 
DoubleDingo

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So what you're saying, the switch works fine, just that pedal, when mashed down to the floor, doesn't trigger the switch? Those are designed to kick down at full throttle and under 55. Well, mine won't kick down over 55.
 
slammed84

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Hamgrease said:
Hey everyone, I have a 85 C10 that was originally a 6.2 diesel/700r4 truck. It now has a 454/400. I’ve installed the kickdown switch solenoid on the petal bracket and made my own harness, it works I’ve tested it. My question is are the accelerator petals different for the TH400 from other transmissions ? My petal doesn’t reach far enough to engage the switch. I’m considering fabricating and welding an adapter rod to it for engagement of the switch.
Click to expand...
I believe that factory TH400 cars and trucks did have an specific bracket that had provisions for the kickdown switch. I've looked into this because I also need to install the switch, but it's been awhile since I Googled it. You could try to research it, I'm fairly sure this was the case.

But I'm with you, I would just fab up a bracket that mounts it in the correct position you need, would probably be easier and cheaper than finding the correct pedal/bracket and whatever it takes to mount it correctly in a squarebody.
 
Hamgrease

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Hamgrease

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It’s way off
 
Hamgrease

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Hamgrease

Hamgrease

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Picture was before I reattached the throttle cable
 
Hamgrease

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slammed84 said:
I believe that factory TH400 cars and trucks did have an specific bracket that had provisions for the kickdown switch. I've looked into this because I also need to install the switch, but it's been awhile since I Googled it. You could try to research it, I'm fairly sure this was the case.

But I'm with you, I would just fab up a bracket that mounts it in the correct position you need, would probably be easier and cheaper than finding the correct pedal/bracket and whatever it takes to mount it correctly in a squarebody.
Click to expand...
The bracket for the switch was actually already on the truck I just had to find a bolt to install it I had one
 
DoubleDingo

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Hamgrease said:
I fixed it today it works perfectly
Click to expand...
Glad you got it fixed and working properly. Having that kickdown with the secondaries roaring sure does get the ticker to tick faster...lol...
 
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