ID of this electrical component?

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Gdub

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I'm in the process of repairing some bogus and burnt wiring under and behind the dash of a new-to-me 1973 C20, and found something that is unfamiliar to me. It's a spring loaded switch mounted on the bracket immediately above the gas pedal (see green arrow in photo). It's a two pin switch fed by orange and brown/white wires. The orange wire goes out through the firewall near the fuse block, while the brown/white wire terminates in a pair of red connectors (shown in second photo). I tried searching, but have no idea what it's called.

Can anyone tell me what the heck this thing is? Thanks!

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Honky Kong jr

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I'm in the process of repairing some bogus and burnt wiring under and behind the dash of a new-to-me 1973 C20, and found something that is unfamiliar to me. It's a spring loaded switch mounted on the bracket immediately above the gas pedal (see green arrow in photo). It's a two pin switch fed by orange and brown/white wires. The orange wire goes out through the firewall near the fuse block, while the brown/white wire terminates in a pair of red connectors (shown in second photo). I tried searching, but have no idea what it's called.

Can anyone tell me what the heck this thing is? Thanks!

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If it’s a TH400 truck it could quite possibly be the kick down switch
 

bucket

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Wtf. Y i no has ones?

Yours shouldn't have had a th400 in it from the factory. Even with the optional sbc400, K5's and K10 Burbs got the th350 it seems. I don't know about pickups, but it was likely the same.
 

gmachinz

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1972 was the last year fornthe carb mounted TH400 kickdown...which imo is a nicer setup
 

donnieray

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My 86 C10 has that kick down switch.
 

Rusty Nail

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Yours shouldn't have had a th400 in it from the factory. Even with the optional sbc400, K5's and K10 Burbs got the th350 it seems. I don't know about pickups, but it was likely the same.


Im curious about the plugs.
Poor truck has gone from a 400/400 to a 350/350.

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bucket

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Im curious about the plugs.
Poor truck has gone from a 400/400 to a 350/350.

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That just says turbo hydramatic, it doesn't specify which.

My old white '77 K5 was equipped the same way, 400sbc with 3.73 gears. And a th350. Same goes for all the other 400 engined K5's and K10 Burbs I've encountered. The only exception is the M1009 units.
 

chengny

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That just says turbo hydramatic, it doesn't specify which.

X2 - prior to 1977 (I think) an M40 RPO was common to both the TH350 & TH400. Which version was installed depended mainly on the engine size/type.
 

Rusty Nail

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I figured m40 was a 400. The th350 seems adequate and I have no evidence of anything else. Absolutely NOTHING looks fishy about that truck. It's actually right as rain.
I've always thought about paying the heritage dudes for their info. It would seem that more info is necessary but I really don't care.
I do shop for th400-np203 adaptors though. Readily available for like $140. I stay on the lookout for a cheap th400 too. It'll may happen one day! Think i'll fix the A/C first lol!

My apologies to the OP, but this thread was over anyways?

Thanks men.
 

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