4l80e swapping my K1500

[350k1500]

You'll need to move a few wires around and add two wires straight to the PCM for the input speed sensor on the 80E (which the 60Es did not have). Info on the trans plug side can be found in this link, but ignore the pinout info for the PCM. They're talking about the newer LS PCMs. To find out what connector/pins you'll need to add wires to at your PCM you'll need a factory service manual with the pinouts for your specific connectors.

https://sites.google.com/site/sloppywiki/everything-ls/4l80e-info

If you're not comfortable with moving the wires around at the plug yourself, or just want to simplify the process, Nelson Performance makes a 60E to 80E wiring conversion kit that simply plugs into your existing 4L60E harness and moves the necessary wires in a little 6" additional section of harness. They also include an input speed sensor harness with the wiring and pins necessary to run that to your PCM. I used their kit on my red '97 C1500 when I 80E swapped it and it worked great.

http://www.nelsonperformance.com/?page_id=850

I have a thread on that '97 C1500 60E to 80E swap here if you're looking for more info. You'll have to deal with some things I didn't due to the fact that your truck is 4WD, though.

https://www.gmt400.com/threads/97-c1500-4l60e-to-4l80e-swap.38819/

Ok thanks I've got everything figured out I've moved the few wires all I've got left is get the driveshaft shortened and add the speed sensor where do i find the pin outs for my truck?

 

[df2x4]

Ok thanks I've got everything figured out I've moved the few wires all I've got left is get the driveshaft shortened and add the speed sensor where do i find the pin outs for my truck?

I found the info for mine in a GM factory service manual. They're available on eBay used for around $1-200. I could give you the info out of mine if you want but they're for '97 trucks, and I know things changed throughout the years.

You might try asking on PerformanceTrucks.net or LT1swap.com, I asked for this same info on Performance Trucks before I thought to look in my manuals and someone there posted the exact same info I found.

 

[350k1500]

I found the info for mine in a GM factory service manual. They're available on eBay used for around $1-200. I could give you the info out of mine if you want but they're for '97 trucks, and I know things changed throughout the years.

You might try asking on PerformanceTrucks.net or LT1swap.com, I asked for this same info on Performance Trucks before I thought to look in my manuals and someone there posted the exact same info I found.

I believe nothing really changed from 96 to 97 if u could just give me the info from yours that'd be great thanks

 

[Supercharged111]

I believe nothing really changed from 96 to 97 if u could just give me the info from yours that'd be great thanks

Cooler line locations changed and I believe bonded pistons came about in 97 as well.

 

[df2x4]

I believe nothing really changed from 96 to 97 if u could just give me the info from yours that'd be great thanks

I take no responsibility if this is wrong and shorts something out in your PCM... I'd really recommend double checking a reference for your specific year and engine. This is the pinout information for the C3 (Grey) connector for a black box PCM in a 1997 C1500 with the 4.3L V6. Pins 7 and 8 are the ISS pins for that specific application.

https://www.performancetrucks.net/f...80e-swap-questions-electrical-1997-pcm-c3.png

EDIT - Just checked my manuals, it's the same two pins on the same connector for the 5.0/5.7/7.4L PCMs in '97 as well.

 

[350k1500]

You'll need to move a few wires around and add two wires straight to the PCM for the input speed sensor on the 80E (which the 60Es did not have). Info on the trans plug side can be found in this link, but ignore the pinout info for the PCM. They're talking about the newer LS PCMs. To find out what connector/pins you'll need to add wires to at your PCM you'll need a factory service manual with the pinouts for your specific connectors.

https://sites.google.com/site/sloppywiki/everything-ls/4l80e-info

If you're not comfortable with moving the wires around at the plug yourself, or just want to simplify the process, Nelson Performance makes a 60E to 80E wiring conversion kit that simply plugs into your existing 4L60E harness and moves the necessary wires in a little 6" additional section of harness. They also include an input speed sensor harness with the wiring and pins necessary to run that to your PCM. I used their kit on my red '97 C1500 when I 80E swapped it and it worked great.

http://www.nelsonperformance.com/?page_id=850

I have a thread on that '97 C1500 60E to 80E swap here if you're looking for more info. You'll have to deal with some things I didn't due to the fact that your truck is 4WD, though.

https://www.gmt400.com/threads/97-c1500-4l60e-to-4l80e-swap.38819/

Ok so i figured everything out i believe but its shifting hard and waiting till like 3500rpms to shift and doesn't have overdrive did i wire something wrong or bad transmission?

 

[Supercharged111]

Sounds like the trans isn't happy with its inputs. Could you explain what you did for the computer and wiring?

 

[350k1500]

Sounds like the trans isn't happy with its inputs. Could you explain what you did for the computer and wiring?

So i got the transmission from a 1996 k2500 parts truck of mine i used the computer from it also my 1996 1500 has the same motor so that should be fine and its not throwing any new codes i switched the wires like that link said and added the speed sensor not 100% sure the speed sensor is in the right spot tbh gonna go over that again tomorrow
(EDIT) found my wiring problem thats fixed shifts fine to 4th but the tc isn't locking or whatever so 60mph is at redline what would cause that (the torque converter is new) thanks in advanced

 

[df2x4]

Wait... What? You say the trans shifts into 4th but you're redlining at 60MPH? Something doesn't add up. 60MPH in 4th gear with an 80E should be somewhere around 2000RPM assuming 3.73 gears and factory tire size.

Did the donor truck have the same gear ratios as your truck? If not your speedometer and shift points are wrong.

 

[350k1500]

Wait... What? You say the trans shifts into 4th but you're redlining at 60MPH? Something doesn't add up. 60MPH in 4th gear with an 80E should be somewhere around 2000RPM assuming 3.73 gears and factory tire size.

Did the donor truck have the same gear ratios as your truck? If not your speedometer and shift points are wrong.

No my truck did have 373 gears but i also swapped the gearing from the parts truck so now it has 2500 axles and 410 gears and it has a 3 inch lift and 35s