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4l80 question

white90burb

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I have a 75 k5 that I put a tbi350 in. Right now I have a t350 and 203 behind it. I originally wanted to make it a rock crawler but have changed my mind recently. I am finding myself wanting overdrive my mpgs are bad around 10 to 12. I was contemplating a 700r4 to 241 swap but then I remembered that the ECM I have came from a 95 van that had a 4l80. In fact the van is still sitting with that tranny in it. So my question is would it be possible to mate that 2wd 4l80 to a 241 tcase? If so what do I need? Or am I better off finding a 4x4 trans?
 
The output shaft in the 4L80 would need to be changed to the 4WD version.

What size tire are you running and what gears in the axles?
 
What size van? Most 95's had the 4l60E in them, I have seen very few vans with the 4l80.
 
Chris I have 35's with 3.73's right now but will be putting 4.56's when I get bigger axles. How much work is it to swap the output shafts? What about adapters do I need anything there?

Gmctruck it was out of a 1 ton van at first I thought it to be a 4l60 until I say on the side it said 4l80.
 
Chris I have 35's with 3.73's right now but will be putting 4.56's when I get bigger axles. How much work is it to swap the output shafts? What about adapters do I need anything there?

OD won't be super useful until you do the gear/axle swap, it won't want to stay in OD.

Changing the output shaft involves completely tearing apart the trans to my understanding. The adapter would be the factory 4WD 4L80 tailhousing/adapter that is still available new from a dealership and they aren't terribly expensive ($100 last I checked).
 
I would be doing the tranny and axles at the same time along with different leaf springs so I only have to change driveshafts once. So if I got that trans and had a shop do a rebuild they shouldn't have any problems swapping the shaft?
 
I would be doing the tranny and axles at the same time along with different leaf springs so I only have to change driveshafts once. So if I got that trans and had a shop do a rebuild they shouldn't have any problems swapping the shaft?

If it's in for a rebuild changing the shaft shouldn't be any extra cost, other than the cost of the shaft.
 
Thanks man I appreciate the help. Do you know what some good upgrades are for these trannies or any links to more info about them?
 
almost anyting you need to know on 4l80 swap to 205 and some 203 stuff.

http://coloradok5.com/forums/showthread.php?t=166233&highlight=4l80

but yes 4wd tail swap and then adaptor all over ebay for those or new. and make sure the tcase you get is 32 spline input. and diffrent crossmember as the newer stuff needs a w shaped crossmember over the flat one of the older stuff like you have. drive shaft length also. but doing the swap any way you were thinking = custom.

good luck and just ask if you need more.
 

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