Manual Trans swap

[ilikemud]

Got an 89 gmc k3500 6.5 diesel with a 4l80 Trans it's my tow rig and it's intermittently losing overdrive and shifting hard 1/2. Comes and goes I've replaced the internal wiring harness and all solenoids still intermittent Trans has 120k and when it works it shifts flawlessly. I really don't like autos and have a chance to pick up a 94 k10 with a 5 speed only issue is will the motor is a 4.3 v6 will that Trans A: bolt to my 6.5 diesel and B: will it hold up to a 6200 pound truck regularly towing 8000lbs? Any help would be great thanks.

 

[sweetk30]

note : my info is if your 89 is a old body style 73-87-91 truck .

if the 94 is a W/T work truck even tho its a 1/2 ton and v6 it should have the nv4500 .

if its not a nv4500 I prob wouldn't swap it .

and the 88-up body style had pass side lower hydro clutch slave cylinder and this can be a problem with less than 4" lift on our trucks since our front shaft goes threw the same area.

otherwise same bell housing and need to do few mods and prob driveshaft length reworking needed. you will need the 85-91 style hydro clutch pedal set and make sure its from a hydro boost brake truck also .

4l80-e good tranny . if its original 120k its prob got sludge and junk inside and ready for reman job . also the seals and clutches are at that age of hard / brittle / thin and ready to go .

might be cheeper in the end to get reman job or crate reman tranny and swap it .

 

[ilikemud]

My 89 is the newer body same as the 94. And I will be getting the whole truck so pedals cross members driveshaft whole 9. The swap should be close to direct.... May eat those words... Bell housing between the 4.3 and 6.5d are the same? And if it is a nv3500 it isn't worth the swap? Thank u for the info

 

[sweetk30]

straight 6 / 4.3 v6 / sbc / bbc / 6.2 / 6.5 / ls = same bell housing pattern . this is 1 major reason like my gm stuff

and buggy building guys doing a 3800v6 s/c from a gtp grandprix use the camero or s10 700r4 with the 2.8 bellhousing pattern to get them a bolt in setup also . cause of the 60* pattern .

 

[Stomis]

My 89 is the newer body same as the 94. And I will be getting the whole truck so pedals cross members driveshaft whole 9. The swap should be close to direct.... May eat those words... Bell housing between the 4.3 and 6.5d are the same? And if it is a nv3500 it isn't worth the swap? Thank u for the info

If its an nv3500 than no dont swap it. Cant tow like that with that trans.