Kickdown switch

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Doubletop

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I just bought an 87 GMC 1500 with a 305 and TH400. Doing general tune-up and fluid changes the other day and I noticed a single terminal switch on driver’s side of tranny. After exploring this forum I’ve determined it to be a kickdown switch. However there’s no wiring or even the switch attached to gas pedal area. I see where it should be mounted but doesn’t appear anything was ever there. Did the 87 TBI have this switch installed here or did they do away with it?
 

Rickf

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Your original transmission may have been changed to a TH400. Does the gear indicator have 3 gears or 4(od)?
 

Doubletop

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Just 3. It has the RPO code for the TH400 also.
 

bucket

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Iirc, the TH350 and th400 used the same RPO code, as listed on the SPID label.
 

HotRodPC

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I'm thinking that would have been originally a 700r4 Truck and someone converted it. But the gas pedal bracket has stayed the same all years that I'm aware of so the switch is not hard to add, and then run a wire to the transmission, and from the switch to an ignition power source.
 

Doubletop

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Thanks for the replies. After looking at wiring schematics I found the truck has a transmission kickdown relay on the firewall. The relay had an open single terminal for a spade type connection sticking out of the harness. So I'm assuming someone just did away with the original kickdown switch and mounting bracket. Now just have to find a new one and get it wired up. I'm not the best at reading schematics. Am I correct that the original wiring went from this relay down to the tranny?
 

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I'm working all day today, but will try to upload some pics tonight or tomorrow.
 

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If you want to do it right, like factory OEM... I've probably got that gas pedal and bracket that supports that switch.
 

Frankenchevy

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They’re proud of those switches. They want $50+ for a simple gas pedal switch.
 

Doubletop

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If you want to do it right, like factory OEM... I've probably got that gas pedal and bracket that supports that switch.

Thanks. I’ve got an 87 Surburban parts truck that may have one on it still. If not I may take you up on that.
 

1987 GMC Jimmy

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If anyone’s parting out any 70s/80s Chevy P30 based motorhomes, they also came with that switch.
 

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