Not on a TH400, if I remember correctly.
I don't know why you would want an NP205 anyway, unless you are building a doubler.
Martin
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
NP205 Swap
- Thread starter Mastiff
- Start date
Not on a TH400, if I remember correctly.
I don't know why you would want an NP205 anyway, unless you are building a doubler.
Martin
The GM setup for the 400 tranny mated to the 203, 205, 280 and 241 t-cases use 3 different output shaft lengths.
The shortest tailshaft fits the 203.
The longer one fits the round 6 bolt, or short adaptor, on 205's and also fits the 208's and 241's.figure 8, or tall adaptor, 205.
The longest shaft fits the figure 8, or tall adaptor, 205.
There has been an aftermarket kit that changes the output shaft in 400's to 27 splines so if a customer had a 350/205 setup and wanted to beef up to a 400, they could simply get the kit and have the 400 rebuilt with the swapped shafts. This kit comes with an adaptor that mates the 4 bolt adaptor to the 6 bolt 400 housing.
Lastly, other than lower gears in a 208, I can't understand any other reason why NOBODY wouldn't want to run a 205. I've seen way too many 208's break in multiple areas than any 205. I don't understand why you keep beating this down on everyone here but when it comes to pure strength, I think a 205 is going to win, hands down.
Last edited:
Without running back up thru all the posts, I take it your 400 has the swapped in 27 spline conversion shaft?
If that's the case, just look for any 27 spline 205 that was behind a 350 tranny.
This picture clearly shows a 32 spline 400 tranny with that 208 behind it.
Yeah, the TH400 must have had a 27 spline conversion. Would that be a direct bolt on to certain 205's? Honestly, I'm having a hell of a time wrapping my mind around all the options.
Does the 400 have an adaptor on the rear? Should be about an inch thick and held on with 6 Allen bolts. Then the 205 with the 4 bolt adaptor will mate to this adaptor on the 400.
If you have this thin adaptor on your 400, then this is the 205 you need:
How about snapping a pic of your 400 at the tailshaft end without the t-case so we can see?
not a expert at the tail shaft swap kits in th400 trannys but . . . .
why not bolt up a np241 from a 700r4 tranny right to the adaptor you got there and get better case over 208 and basic bolt in and go .
maybe greg ducato member here can chime in . he is around mon-friday mostly .
why not bolt up a np241 from a 700r4 tranny right to the adaptor you got there and get better case over 208 and basic bolt in and go .
maybe greg ducato member here can chime in . he is around mon-friday mostly .
It's kind of too late since I already bought the 208 SYE kit, but I didn't think the 241 was significantly stronger than a 208. Why do you see it as an upgrade?
I did keep an eye out for 241 and it's not like they are giving them away.
I did keep an eye out for 241 and it's not like they are giving them away.
That shaft is small in that pic. Definitely 27 spline.
If your 400 is working fine, I'd just use the 208 or 241 if you can find one.
The 241 is an upgrade over the 208 because you can get SYE's for them and its got a lower range than the 205.
I'd definitely choose a 241 over a 208 any day.
But for bombproofness, a 205 can't be beat.
I understand there's some confusion with the 205 and the output/input shafts it takes to get mated to the correct tranny.
I bought a SYE for my 208. Tom Woods makes them. Seems like a decent route for now, but if there's a 205 that could mate to my 27 spline output, that would be good info for down the road. Otherwise I just wait until I feel like spending big bucks and pay someone to put my 400 back to 32 splines and get a doubler. I really don't need that right now.
I think you can swap a TH400 output shaft out the rear. I might be wrong. I know there is a GM transmission that you can.
Martin
Martin
Doing some reading. I may have been talking out my ass.
Martin
Martin
