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Perez620

Wiring a 5 spd trans to an auto trans truck

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 Its time to wire up my 5 speed into my truck. 

 

My truck is a 1974 620. Originally an L18 auto trans and is now L20B 5spd. 

 

As expected the transmission wiring isn't a direct plug and play going from auto to manual trans. 

 

Has anyone done this conversion and has info on how to wire the 5 spd harness to the existing truck harness? I've attached a few photos of the 5 spd harness, the existing truck harness, and of the 5 spd that is now in the truck. The one photo out of the transmission manual is one I found online that is a similar trans out of a 200sx.. its not a FS5W71B like mine. 

 

Any help would be much appreciated! 

 

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IMG-0110.jpg

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Edited by Perez620
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IMG-1026.jpg

 

Join the Black/White stripe wires together. This is the transmission interlock and are only connected in PARK and NEUTRAL so you cannot start in gear. If you don't join these two the starter won't engage during START.

 

The Red/Black stripe wires are for the reverse lights. Connect these two to the mates on the 5 speed reverse switch. (polarity not important)The reverse switch is closest to the front of the transmission directly behind the clutch arm dust boot and approximately half way up the right hand side about where the passenger's knees are.

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Thanks Mike. 

 

I forgot to include a photo that is two wires on the driver side truck harness. There’s a yellow with red stripe and solid black. Anything to do with these?

 

also, you’re saying I don’t even need the harness that came with the 5spd to wire it up correctly?

 

https://postimg.cc/gallery/1m31qo7k8/

 

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The truck harness is slightly neater with 2 less wires. Either works.

 

C3-B322-AF-1-D9-C-4-B4-A-BBC4-366-D3-D9-

 

Don't know about this one. Does it reach near the carburetor?

 

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No the black and Y/R wire lay on the driver side of the trans. Looks to be for the kick down solenoid according to this wiring diagram? 

 

D7-B801-F8-6-A40-4-D6-E-8-F27-6-A29-F9-E

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Of course. The kick down. Just tape it up out of the way. There will also be a small vacuum line from the intake down to the modulator valve. Probably cnnects at or near the vacuum hose for the brake booster. Make sure it's sealed up.

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Ok great. Already have the vacuum line capped. So just to be clear on everything, can you please confirm or change anything I need to do below. Please confirm if edited picture is correct. 

 

1. Connect both black/white stripe wires from truck harness for starter to operate 

 

2. Connect the red/black wires to reverse switch - two black wires coming off transmission closest to clutch fork

 

3. Tape up kick down solenoid wires and do not use 

 

4. Make sure vacuum port is capped on top of intake 

 

5. Do not use or attach ANY of the wires that came with the 5 speed harness 

 

4-DF017-D6-F27-A-4-E56-822-F-EF977-B94-D

Edited by Perez620

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10 hours ago, datzenmike said:

Of course. The kick down. Just tape it up out of the way. There will also be a small vacuum line from the intake down to the modulator valve. Probably cnnects at or near the vacuum hose for the brake booster. Make sure it's sealed up.

 

Bump for previous post

 

Trying to to get this wired up tonight. Appreciate the help Mike 

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The other switches are for emissions and it will run fine without them.

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