4l80 205?

[kleedus]

i may be going with a 4l80 in my crew cab and i have an idea for putting a 205 on it.

from what i have found the 4l80 has a 32 spline output shaft and uses the round 6 bolt style t case adapter.

if thats correct my 205 out of my 90 crew cab might bolt up to a 4l80.
it has 32 spline input and uses the round 6 bolt adapter.

has anyone done this or know any different?

 

[oneluckypops]

i may be going with a 4l80 in my crew cab and i have an idea for putting a 205 on it.

from what i have found the 4l80 has a 32 spline output shaft and uses the round 6 bolt style t case adapter.

if thats correct my 205 out of my 90 crew cab might bolt up to a 4l80.
it has 32 spline input and uses the round 6 bolt adapter.

has anyone done this or know any different?

what Transmission is in it now?

4L80E and TH400 share the same Transfercase adapter


DOAH I think there is a year break though have to check to make sure

 

[kleedus]

if i am remembering right it has a 32 spline output sm465 86 and up.

i think the turbo 400 and the 86 and up sm465 the t case will interchange so it should swap to the 4l80.

but if that fails i do have a turbo 400 205 combo i can use that t case if what you said is correct

 

[oneluckypops]

if i am remembering right it has a 32 spline output sm465 86 and up.

i think the turbo 400 and the 86 and up sm465 the t case will interchange.

if it will in fact mate to a TH400 it will also mate to the 80E, No year break on the 80E. I got the 60E confused in with the 80E

 

[kleedus]

ok that makes that easy for me i have a 400 205 and know how to mate the 205 to a 400.

 

[bucket]

You can use the 400 adapter, but it's not a direct swap. It has something to do with a sealing surface, I don't remember the specifics. The correct adapter is a one year only (and crew cab-only) and finding one is like finding a needle in a haystack.

 

[nvrenuf]

The '85+ round pattern 205 will indeed work with the 4l80e using a '85+ th400adapter.

To use the 400/205 adapter you'll need to machine an o-ring seal groove on the trans side and part of the adapter casting will need to be ground off as it hits the trans case (I believe around the mounting foot).

The true 4l80e/205 combo was only found in a '91 V3500 crew cab.

 

[kleedus]

what t case came behind 4l80 in stock trucks was it 241 or something like that

if the stock t case behind the 4l80 used the round pattern would that adapter work with a round pattern 205?


my nv 4500 had a 241 behind it and i put a 208 behind it in my 85 and was told the round pattern 205 would also bolt up to that.
but i would have to grind for shift rod clearance and make a shifter mount.


so i am curios if the round pattern 205 will fit the stock 4l80 t case adapter with minor mods

i am not sure just running thoughts by you guys to see what comes from them

 

[Berg]

I think you can do but but you have to check the length of the input shaft on the transfer case VS the output shaft on the trans. I think there was an issue with spline engagement IIRC. I was kicking this idea around for my 99 Burb but ran into problems with the VSS and whatnot. If it doesn't work there are guys that do custom adapters over on that butt-pirate forum. I think one guy is in CT and has most of the specs to work with certain combos. I also understand if you don't feel like spending an extra $300 and can save some money with a die grinder and a factory adapter.