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Cucv M1008 4l80E swap

lukeM1008

New member
8
22
3
Location
oregon
I realized for me to drive my cucv around a lot and for it to be practical I needed an overdrive. I looked at a lot of options such as nv4500, gearvendor, ranger+sm465 but I found the easiest and probably the cheapest swap for me was going to be a 4l80E. Right now I have most of the parts I need to do the swap and I have spent about $875 but I still need to get the rear drive shaft shortened and front one lengthened. I found a deal on facebook marketplace for a 4l80E, np241, and a seized 454 all for $200 so I bought it and then sold the seized big block for $120. I pulled the pan off the 4l80E and it looked really nice inside and the fluid was not burnt so I put a new filter in it and I am planning on using it as is. I also am going to try to use the torque converter that was on it because it is probably a low stall one. Since the 4l80E is electronically controlled I needed a stand alone kit to control it so I got the Painless Performance Perfect Torc kit. I went with the Perfect Torc kit because it was the only kit I found that didn't need a tachometer input from the engine I also had to get a throttle position sensor for the stand alone computer to work so i got a acdelco one made for the 6.2 diesel and it just bolts on the injection pump where the vacuum valve for the th400 shifts used to be. my plan for the trans cooler is to use the stock in-radiator th400 one because i don't plan on hauling heavy trailers in hot weather and it will work out nicely because the 4l80E i have is the earlier one with the cooler line ports both in the front so they should be able to use the th400 cooler lines. In a couple days i’ll commit to pulling the th400 and post more about drive shaft length, the cross member situation, and shift linkage. IMG_4610[1].JPGUVOB7537[1].JPGIMG_1330[1].JPGIMG_1332[1].JPG
 
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lukeM1008

New member
8
22
3
Location
oregon
Killer deal! I found this that may help you id the TC. I have heard that they can be the same but then again, better safe than sorry. Good luck!
Thanks for the info but I couldn’t find any numbers or anything stamped on my tc so I was just going to take my chances.
 

cruzer747

Active member
218
145
43
Location
California
Thanks for the info but I couldn’t find any numbers or anything stamped on my tc so I was just going to take my chances.
no fins cast onto housing as described in pdf? The angle is supposed to let you know low or high stall.... (looking at the hub swirl counter clockwise = low and clockwise = high... just in case you missed hat bit and for anyone else who digs this up later)

Just noticed you have a goodwrench sticker on there so my guess is it has been replaced at some point.
 

lukeM1008

New member
8
22
3
Location
oregon
no fins cast onto housing as described in pdf? The angle is supposed to let you know low or high stall.... (looking at the hub swirl counter clockwise = low and clockwise = high... just in case you missed hat bit and for anyone else who digs this up later)

Just noticed you have a goodwrench sticker on there so my guess is it has been replaced at some point.
oh ok thanks I missed that about the fins and yes I believe the transmission was rebuilt or replaced recently because it looked pretty good inside
 

lukeM1008

New member
8
22
3
Location
oregon
no fins cast onto housing as described in pdf? The angle is supposed to let you know low or high stall.... (looking at the hub swirl counter clockwise = low and clockwise = high... just in case you missed hat bit and for anyone else who digs this up later)

Just noticed you have a goodwrench sticker on there so my guess is it has been replaced at some point.
I just looked at the tc it has the low stall pattern of fins so now I’m sure it’s low stall thanks again for the infoE60D05EB-7F85-46CA-A092-8B79CB9AF346.jpeg
 

lukeM1008

New member
8
22
3
Location
oregon
I welded some square tube to the cucv crossmember and used some 1in spacer between the trans and the rubber isolator. the turbo 400 dipstick worked with only one bend at the very top to get it more pointed forward
5A1D709C-CD4F-441D-A7A4-EA4B69680DCB.jpeg1B306B51-2E7D-493B-9186-A4FE67631BB1.jpegC872DB5B-7C82-4013-B96E-75F65A5AC0C9.jpeg
 

lukeM1008

New member
8
22
3
Location
oregon
Why the cross member mount square tubing? Mine bolted on without issues. What are your rear drive shaft angles now?
The th400 tcase adapter is like 4in taller than the one on the 4l80e. so the 4l80e+1 in spacers+The square tube +the rubber isolator made it the height of the th400 adapter. the drivshaft angles are exactly the same as when the th400 was in it.
 

lukeM1008

New member
8
22
3
Location
oregon
2EF2704E-2C5B-461D-B2A5-D0FE7A230480.jpeg037AF662-0481-4B89-BA22-AFB733BC1B4A.jpeg776B4C4F-77E3-4506-98C3-08D41383A03E.jpeg2A509A13-400C-4932-9D6A-A65919EA21A4.jpeg
Sorry for the wait. I did all the little things like wireing, linkage lengthening, and cooler lines while I waited for my rear drive shaft. I got it shortened exactly 2 inches and it cost me 200 bucks. The truck is driving now and it cruises over 55 no problem. I used the diesel program on the transmission controler and just set the shift points down so it shifted sooner and smoother. I waited to do the front drive shaft because it was going to cost over 500 bucks so I’ll figure out some way to lengthen it myself and post about how that goes.
 

mtperkins

Member
52
31
18
Location
Cazenovia,NY
Did you get it working?

My 4l80e is missing the output VSS. Kind of at a stand still until i figure out what to do.
 
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Keith_J

Well-known member
3,657
1,323
113
Location
Schertz TX
Later 4x4 4L80s used transfer case speed sensor output for speedometer and transmission controller use. I would recommend either have the transmission modified with output tone ring or add a tone ring to the transfer case adapter. Advanced Adapters does this on some 205 transfer cases to 4L80.

Aftermarket controller may not work in low range if you use the transfer case output for speed sensing.
 

socalsrt

New member
11
22
3
Location
california
If it is a 4wd 4L80E, pull the rear speed sensor plug out and see if the reluctor tone ring is already installed. I have seen two, post-2000, 4wd 4l80Es with the ring installed for whatever reason. When I rebuilt my 4wd 4l80E, I just added the rear reluctor tone ring. Unfortunately to install it, most of the transmission has to be disassembled. Other than that, The only realistic option is what Keith_J is saying with adding it to the T-case....

Also, I really like the 4l80E with 4.56 gears and 33" tires. Makes for a nice driving truck. You will not regret this mod!
 

mtperkins

Member
52
31
18
Location
Cazenovia,NY
Thanks Guys. Great info. I am mid cab swap right now. I wanted to swap the transmission at the same time. But I think it best to have it rebuilt and tone ring added before I install it anyway. Currently have my hands full with installing a civilian AC equipped cab on a non AC chassis. Just a way more solid cab to work with. Turned out to be a lot more work than I thought. The NY rust has mine looking like Fred Flintstone had the truck.
 

McLovin

Member
Please keep us up to date, thanx.
Planning to replace th400/np208 on my M1009 with a 4l85e/np241c vss.

PS: checked the painless performance site:

That product has been discontinued :(

What controller do you recommend for that swap?
Thank you.
 
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chevymike

Well-known member
597
463
63
Location
San Diego, CA
This would be the controller I would buy, if/when I do a swap. Seems to be one of the better ones out there.

 

McLovin

Member
Thank you @chevymike I will evaluate it :)

For the TPS, is this the right one?

And what adapter between 4l80e and np241 I will need?
As I'm sitting in Germany, will this one work for me?
or

PS: its a M1009, so that adapter should be a short one, as I have already a short wheelbase :(

Thanx
 
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