th400 to np241

[Cole]

i have a 1986 k20 silverado with the np208 t-case which needs to be rebuilt...i also have a np241 from a 1989 k5 is it possible to just swap out cases...will i need an adapter if so who makes them...im looking for the cheapest and easiest way to get the silverado up and running so i can get out on the trails.
Thanks, Cole

 

[ryan22re]

Adapters are the same. Bolts right up.

 

[wayne]

You need a 32 spline input for your 241 if it came from a K5 with a 700r4 trans and you are putting it behind a th400. As mentioned it will bolt to your existing adapter.

 

[tavis]

Yes you either have to find a 32 spline input np241 from behind a 4l80e/NV4500 or replace the input shaft on the T-case (GM part#12547998)

I am assuming that the current setup is TH400->np208. If you currently have the a 700r4->np208 you will have to move the crossmember forward ~1.5" to accomidate the shorter TH400.

T.

 

[thatK30guy]

Shouldn't have to move the crossmember at all.

 

[Cole]

is it possible to swap the input shaft from the 208 to the 241...

 

[mikey_d05]

I doubt it, but new inputs are easy enough to find. Make sure you get the bearing along with input. When I swapped my input for a 32 spliner the original bearing was too thick.

 

[wayne]

is it possible to swap the input shaft from the 208 to the 241...

No.

 

[wayne]

I doubt it, but new inputs are easy enough to find. Make sure you get the bearing along with input. When I swapped my input for a 32 spliner the original bearing was too thick.

When I did it I didn't need to swap any bearings. Do you have a part number for the bearing you used compared to the origional?

 

[mikey_d05]

Nope, but I do know that my case was a passenger drop and the case I got the input from was a driver drop. My case is an '89 but I have no clue what year the other case was.

 

[wayne]

Nope, but I do know that my case was a passenger drop and the case I got the input from was a driver drop. My case is an '89 but I have no clue what year the other case was.

That might be it. My inputs came from pass drop cases.

 

[hack500]

another thing to keep in mind is that a 241 has a different overall-length than a 208.

 

[jp0863]

i did it in mine, all i had to do is swap the input, very easy and it cost me about $30 from jb conversions. i also did the sye on mine too so i needed new driveshafts anyway. if i recall correctly the input is 6 bolts, but very easy to do. slap on some silicon and call it good. dont know much about whether or not the stock drive shafts would work, but they should.