'97 C1500 4L60E to 4L80E Swap

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df2x4

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What I meant regarding the VSS was that I already have the jumper harness on the way, and the kit comes with the second sensor and wiring to go with it. I'll relay what you said to my mechanic and see whether or not he wants to use the harness. If not, then I'll either send it back or resell it. Appreciate the info, though.

Also appreciate the mention about the trans mount, I was wondering about that myself. I actually priced out the factory mount when I was doing my research and selected the cheap-o due to the price difference, figured how much worse could it really be? I should have known better. I'll be going back and editing the post with my parts list to reflect this revelation, I don't mind spending some extra cash for OEM parts if they're worth it. I'll probably at least grab an OEM filter kit in addition to the mount.

Side note, think I've found an inspection cover that isn't a discontinued part for a little cheaper. Not sure what the difference is, new part number I found is 15687274.
 

df2x4

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Small update, still just gathering parts. Went and dropped off the shift kit and TC bolts with the truck and ran it for a little bit to keep some charge in the battery.

So I've been informed by Nelson Performance that their 60E to 80E conversion harness is for V8 trucks only. According to them the pinout of the connectors is different on the V6 trucks. I've sent them an email asking if they can customize the harness for me as I really want to keep the electrical work to a minimum. If they won't do it then I'm going to try Hughes Performance. If neither of them are willing to customize the conversion harness then I guess I'll be doing it the old fashioned way like @Supercharged111 suggested. My mechanic will have to add the two wires at the PCM for the 80E speed sensor anyway so I'm sure it won't be too much of an issue for him to wire up the 80E connector.

Speaking of which, does anyone know what Nelson is talking about? I had assumed that the transmission wiring would be identical between the V6 and V8 trucks, so the information they gave me today was a little surprising. Any info that anyone wants to share about the electrical end of this swap (V6 or V8 related) would be great. I'll update the more I find out, going to check the FSMs and do some Googling. Also going to send an email to Black Bear and ask them which two pins on my PCM will need to be wired up to the speed sensor on the 80E.
 

df2x4

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So from what I've been told by some knowledgeable folks over at PerformanceTrucks, there is no wiring difference between the V6 and V8 trucks like Nelson told me. I guess Nelson was just covering their *****. ISS goes to C3 (grey connector) pins 7 and 8 at the PCM, and the transmission connector repinning is the same as a V8.

Cancelled most of my Nelson order, now they're just shipping me the ISS and wiring/pins. Going to have my mechanic repin the transmission connector according to these directions and the electrical should be good to go!

https://www.performancetrucks.net/forums/gm-drivetrain-suspension-22/4l60e-4l80e-wiring-swap-413157/
 

Supercharged111

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Glad you finally came to your senses. If your mechanic can't swap a couple pins for less than the cost of a conversion harness then he needs to seriously rethink breathing.
 

df2x4

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Glad you finally came to your senses. If your mechanic can't swap a couple pins for less than the cost of a conversion harness then he needs to seriously rethink breathing.

:lol: Agreed. It was never a question of his abilities, more my OCD taking over and me overthinking the hell out of everything. But yeah you're right, $100 for moving a few wires around is pretty silly.
 

timusry

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I believe the driveshaft will need to be shortened. 80e is longer then the 60e. At least that's what I have figured on my 4x4. I could be wrong on the 2 wheel drive side.

Sent from my SM-G930V using Tapatalk
 

df2x4

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I believe the driveshaft will need to be shortened. 80e is longer then the 60e. At least that's what I have figured on my 4x4. I could be wrong on the 2 wheel drive side.

Sent from my SM-G930V using Tapatalk

Yeah I'm pretty sure that's going to be necessary. Thanks for the input.

Did some research on transmission coolers today, I'm going to go with the Tru-Cool M7B. Wanted to do the Tru-Cool Max 40K, but that would require relocation of the horn and a lot of other trimming and thought in general. The Tru-Cool M7B appears to be the exact same unit as the B&M 70266 mentioned in this thread, but less than half the price.

http://www.gmt400.com/threads/how-to-factory-auxiliary-trans-cooler-upgrade.18104/

Going to hook the factory cooler in the radiator back up as well, that was bypassed after my last 60E rebuild.

Not sure exactly what I'm going to need as far as fittings and lines, might just let my mechanic take care of that. None of my factory hard lines are going to work anyway so I'll probably have him make up whatever sort of flexible line setup he's comfortable with.

EDIT - Might actually go with a different cooler kit, Tru-Cool LPD4589. Simply because it comes with installation hardware and some hose. The only other difference is that the LPD4589 has 11/32" hose barb fittings instead of the 1/2" NPT like the M7B. Which as I see it makes no difference for my application. Also might pick up a 25ft roll of Derale 13007 11/32" ID transmission fluid hose.
 
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df2x4

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Nah, sticking with the M7B.

Still gathering (hoarding) parts for this. Life got in the way temporarily.

I've been researching torque converters some more based on mixed reviews for Dacco. I've got an email out to Coan Racing to see if they can build me something. If they can't, there's a B&M Traveler that looks like it would work nicely. On that note I have a question for the transmission savvy...

The junk yard 4L80E I bought came from a 350 truck, which tells me that the converter in my transmission should be similar to a Dacco B81. That would put it's stall speed at 1600-1800RPM according to the Dacco catalog. The B82 that I originally picked out for this swap has the stall speed listed as 1800-2000RPM. That seems like a pretty negligible difference to me.

Should I save myself some money and use the junk yard converter with the 1600-1800 stall speed, stick to the plan and order the Dacco B82 with the 1800-2000 stall speed for $175, or spend $500 on a custom Coan Racing converter with a slightly higher stall than that? Personally I'm leaning towards just using what I already have but I'd like to hear everyone's opinions.
 

Supercharged111

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The small block trans should have come with the B82, is there no sticker on the converter? I have a B82 and don't wish for any more stall than that. It's noticeably more stall than the 1600 or so that the 4L60 came with.
 

df2x4

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Nope, no sticker. Like I posted earlier in the thread, everywhere I've looked lists the B82 as V6/high stall. Even on Rock Auto when you pull up a small block Express Van or truck they list the B81. Change to 4.3, B82. That's why I'm assuming I have something similar to the B81.
 
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