th400 output question

[dstang97]

Has anyone cut the output shaft on a 2x4 tranny to work on a 4x4. I just picked up what looks to be a 2wd tranny with a 208 attached to it. I havent split it apart yet. Any difference in strength between the 2wd and 4wd?

 

[Westech]

yes just the output shaft. If you put in a 4x4 shaft and take the tail housing off it will work.. but to do that you need to disassemble the trans.. so your better off getting a 4x4 one.

 

[ODdave]

HUH, looks to be a two wheel drive trans w/ a 208 attached to it but you havent split them? i am confused as to how it looks like a 2wd?????

 

[4bogginchevys]

I too am confused how it would look like a 2wd trans...the tailshaft is the kicker. Today I made a 2wd into a 4wd, used the output from the 4wd trans in the 2wd case, perfect fit. It is a little decieving on the output shaft on a 2wd with the tail housing removed....it looks like you could just cut of the excess shaft and mate it with the 208 as you said. Not the case, the splines are not cut long enough on the 2wd output, otherwise it would be that simple. The splines need to be cut about another inch toward the rear of the case for that to work, the spline count is the same.

Edit: if it did work i'll be pssed because I just got done making a switch that wasn't necessary

 

[dmc-4359]

Someone who is unfamiliar with the th400 might not realize the 2wd and 4wd slushboxes are identical except for the output shaft and tail housing. If someone were coming from a purely hot rod background, they'd recognize the transmission as being a standard th400 except for the tail shaft and might describe it as a 2wd transmission used in a 4wd application.

 

[4bogginchevys]

you can also look for a speedo gear/housing to be present on a 2wd case. The 4wd case should just have a freeze plug looking thing block off where that would be. Speedo is in the transfercase on 4wd. Hope it helps.

 

[POOR WHITE BOY]

2x4 and 4x4 turbo 400 transmission cases are not identical the 4x4 models use a hd case which has thicker ribs cast into it around the torque converter areas. The cast aluminum dust cover will not bolt on a 2x4 case. The 2x4 case uses a stamped steel or even plastic dust cover held on with small screws. The cast aluminum dust cover is made to also hold the strut rods that go to each front motor mount. I would not even consider putting a turbo 400 from a 2x4 in any of my trucks. Because of this. Sit the 2 side by side and compare the difference in thickness of the case/metal in bellhousing area.they also made 2 different output shaft lengths in the 4x4 models.

 

[Alucard-HD]

2x4 and 4x4 turbo 400 transmission cases are not identical the 4x4 models use a hd case which has thicker ribs cast into it around the torque converter areas. The cast aluminum dust cover will not bolt on a 2x4 case. The 2x4 case uses a stamped steel or even plastic dust cover held on with small screws. The cast aluminum dust cover is made to also hold the strut rods that go to each front motor mount. I would not even consider putting a turbo 400 from a 2x4 in any of my trucks. Because of this. Sit the 2 side by side and compare the difference in thickness of the case/metal in bellhousing area.they also made 2 different output shaft lengths in the 4x4 models.

I've seen a HD 2wd Turbo 400. It sad HD right on top of the bell housing, me and a friend just put one in his 2wd Chevy step side. And maybe im a moron for saying this who knows but he said its a 2wd turbo 400 with a 208 attached to it, maybe its a divorced 208??? I dont know i guess i just wanted to throw that out there.

 

[ODdave]

w/ the exception of the "divorced 208", no such thing....

 

[POOR WHITE BOY]

I have seen a hd case in a 2wd also - but not oem from gm/chevrolet. Even motorhomes /or a p chassis as they are called did not use a hd case. A divorced np 208 - now that there is funny - seen them custom built for mud racing. Good point - i bought a used 1989 v3500 4x4 and someone had put a 2x4 turbo 400 in it - and it had a cracked bellhousing because of how thin they are.

 

[dstang97]

yes the tranny I picked up has a speedo and Stamped steel cover. So pretty much you guys are saying the output shaft must have been switched out to hold the existing 208?

 

[POOR WHITE BOY]

Stamped steel cover = 2x4 case short and sweet

 

[dstang97]

I know I already said that people were doubting me I guess when I get home ill split the case and repot back. The kid wants 100 for it think its worth it?

 

[POOR WHITE BOY]

THE OUTPUT SHAFT COST $185 FROM GM IF YOU NEEDED ONE

 

[dstang97]

I just thought abou what you said about the case strength will it hold a 205?

 

[Alucard-HD]

w/ the exception of the "divorced 208", no such thing....

Yea i didnt think so either, unless someone custom made it, but for a 208 that would be a waste of time.

 

[Alucard-HD]

I just thought abou what you said about the case strength will it hold a 205?

Not to throw a wrench in the works (no pon inteded) but spline count makes a difference too, if my memory serves me correctly the Turbo 400 had a spline count of either 28 and or 32. Please correct me if i'm wrong. because i think i am, lol

 

[POOR WHITE BOY]

LOTS OF STRESS WHEN LOCKED IN 4LOW,THE PROBLEM WITH THE 2X4 CASE ALSO IS IT CANNOT BE MOUNTED CORRECTLY WITH THE STRUT RODS GOING TO THE ENGINE MOUNTS.
I AM INTO SLED PULLING WITH ONE OF MY TRUCKS - I HAVE SEEN ALOT OF CARNAGE . ANOTHER SOLUTION IS AFTERMARKET STEEL BELLHOUSING FOR ADDED STRENGTH - JW MAKES ONE FOR THE TURBO 400 - SAWSALL YOURS OFF AT THE FRONT PUMP AND BOLT THE JW HOUSING ON GO ON YOUTUBE TO : POOR WHITE BOY . THATS THE TRUCK IN MY SIG . SEE THE ABUSE THAT I GIVE MY TURBO 400

 

[POOR WHITE BOY]

All turbo 400 and 4l80e have a 32 spline output shaft

 

[dstang97]

Thanks for your help I'm gonna hold out I'm uff on everything I own and was gonna swap my 205 in while it was out I plan on doing sleds fourwheeling and towing. While we are talking about trannies and such will a 203 yoke work on a 205