CUCV 4L80E Converison

[pigfoot63]

Thank's guys for all the info. Im going to get the books out do some research round up a few more parts and then call a couple of my buddies for a beer.

 

[acmunro]

Bringing up an old thread. If I have a 1986 NP205 transfer case that was behind a TH400 can I take a early 90's 4L80e 2wd trans remove the tailhousing shorten the trans output shaft to get the correct stickout, then bolt the stock 400 adapter and NP205 to the 2wd trans ? I think 1986 is the first year for the round pattern 205.

What flexplate/flywheel would you use with the 4L80e the stock TH400 ?

Is the 4L80e 4X4 transmission case stronger than the 4L80e 2wd or are they the same ?

Thanks in advance.

 

[POOR WHITE BOY]

The 4l80e np 205 t case adapter was only used in the 1991 v3500 models. The 400 adapter you have will not work. The 91 model 205 case also had a speed sensor on the tailshaft - so your tranny will shift properly - even when in 4 wheel drive. This adapter and case is very hard to find. You can use the older style 1977 thru 1984 turbo 400/np 205 adapter with older style case with some minor machine work. All 4l80 e trannys use the hd or heavy duty / 4x4case. The flex plate would depend on engine not so much tranny - hope this helps

 

[acmunro]

Thanks, Looks like I will have to dig up some different stuff.

 

[pigfoot63]

Still rounding up parts for my conversion, have the transmission, transfer adapter,throttle position sensor and two different types of speed sensors, am working on trans control module problem now. going to try to do all this without buying the compu shift controller. Will post when completed .

 

[noel.isaac]

this may be a dumb question, but why not just put in a 4l80E with it's factory attached transfer case, like what came out of my 94 3500 4x4...then the only changes are the shifting linkage linke, comptroller addition, drive shaft lengths and the crossmemmer location? This is what I was going to do next month as my 400 is smoked after dragging a skid loader around this weekend.

 

[acmunro]

The front drive shaft would be on the wrong side.

 

[POOR WHITE BOY]

this may be a dumb question, but why not just put in a 4l80e with it's factory attached transfer case, like what came out of my 94 3500 4x4...then the only changes are the shifting linkage linke, comptroller addition, drive shaft lengths and the crossmemmer location? This is what i was going to do next month as my 400 is smoked after dragging a skid loader around this weekend.

lol - post some photos of your front driveshaft - installed- lol

 

[noel.isaac]

lol - post some photos of your front driveshaft - installed- lol

I am so retarded....i totally forgot it was on the left after 87 or so...now I need read up on all this adapter crap. sorry guys for the brain fart.

 

[dstang97]

does it matter if the tranny originally came out of a gas job? or is it just like the th400 different tC?

 

[pigfoot63]

Just swap converters

 

[mtjbrown]

AA,does in fact,make an adapter...i'd have used one if it didn't cost something like 650$,not including shipping.as it turns out,the aa adapter looks exactly like a racetrac adapter.it just has the right indexing ring...so i used my nearly free one,and spent 80$ to have a competent machinist give it a close shave...

Fleet Admiral...your correct,sort of.the compushift is rather expensive...about 1100$,options dependent.but it's very complete,and easy to both use and install.the so called "beumanator" controller is about 650$...but needs things like a wiring harness etc,and is little more than a set of switches.the pcs controller is more pricey,needs a laptop to program it,and requires both a wiring harness and a tps setup to work.it also is not friendly with people who need "tech supprt" on a regular basis.(and pcs has a rather poor rep for after purchase support).

that gives us only one really cheap option...manual control.a manual valve body mod can be made to the 4l-80,that turns it into a "manumatic".it requires little more than a vacume source for the line pressure control.about 300$ or so for the kit...not including install.

Not trying to be smart-a** what exactly is a "racetrack adapter" I am very interested in an overdrive tranny for my M1031 as it kills me to run 55 or 60- all the time>

 

[pigfoot63]

I am using the np208 transfer and the compushift controller

 

[dstang97]

Not trying to be smart-a** what exactly is a "racetrack adapter" I am very interested in an overdrive tranny for my M1031 as it kills me to run 55 or 60- all the time>

Its a way of describing a older style NP205 it has more bolts than the newer circle bolt 205

 

[dstang97]

I am using the np208 transfer and the compushift controller

Will the 205 round pattern bolt up? I thought I read that most of them will and you just drill the others that don't line up. Maybe I'm thinking about the NV4500.

If you have a compushift controller is it easier to use the 4x4 or is the 2x4 better and switch out the tail shaft?

 

[pigfoot63]

You need tobe able to run a T.O.S.S. sensor . The later model 4L80E 4X4 trans has this.
I have heard of using the two wheel drive model but how done no research on it.

 

[POOR WHITE BOY]

Speed sensor needs to be on the t case or you will not have accurate reading /operation when in 4 low

 

[dstang97]

besides having my spedo off in 4low
What is a list of parts to make a 4l80e/np205? besides Compushift controler

what year tranny/ generation?
2wd or 4wd?

 

[POOR WHITE BOY]

You need a 4l80e 4x4 tranny. The np 205 had a speedsensor in the tailshaft section - 1991 v 3500 series models only.. You also need the correct adapter i have photos in another post. The strut rod - torque rod is longer on this combo. The 4x4 shift lever is angled different - so without the correct shifter you either have to cut a new hole in your floor or bend - fabricate a older shift lever.the driveshafts will be a different length as well. I have done this conversion with a 454 engine and i also own a 1991 v3500 with this set up oem. Hope this helps with your swap