SBC 700r4 what transfer case?

[Cataldo]

Hello everyone,

I know this has been asked oh once or twice (OK a lot more than that I am sure), I am trying to gather as much information on SBC 700r4 swaps. The adapters negate any savings from keeping your T/C. This would be in pre 76 FSJ, keeping the passenger side axles would have to be kept, to keep costs down. I have seen people recommend NP205 and NP208's from off of a Chevy trans (TH400/TH350?). I Have no experience with either, obviously quite different though.

Are there other good options for transfer cases?
What Issues are people having with them once they are done?
Driveline angles?
Bad Vibrations?
Tips and tricks/Words of advice?

Some Fab work is nothing, new drive shafts front and rear are expected.

Thanks

[marcallen]

I had settled in on a NP241, from 88-91 passfull-size Blazer/K5/Suburban, passenger side drop when I was doing a 700r4. I'm doing a 4l60 behind an LS 5.7, but the setup is essentially the same from the trans back. I've seen a few trans crossmembers dropped a bit to get the right angle but I'm fabbing mine so it doesn't hang low..er. I'm back on the driveline in the next couple weeks and plan to post it so if you're not ahead of me you can watch me hurt myself. It maybe overkill some but I'll be moving or keeping things loose and using corner weight scales to see where it just doesn't fit, but is balanced with full tanks, batteries, etc. I have the tailshaft adapter for the R4 to NP incidentally if you get to where you need it. It was $40.00 or something like that with my case, rebuilt. I'm assuming this was a Quadratrac Jeep ? I've got a 76 here too, for reference, with a 1339 case, the 401/400 live in a Javelin now..another LS waiting on that one.

[cmaje72]

Either a NP208 or a passenger drop NP241 would be fairly easy behind the 700R4. I have a driver drop 241 behind a 700R4 in my wag now with the stock crossmember the farthest set of bolt holes and it fits great. I have never owned a pre-76 truck though so I can't advise on the fitment there.

[Cataldo]

Ah, yeah the NP241 looks like a real viable option.

Thanks

[Cataldo]

http://www.gmsquarebody.com/forum/showthread.php?t=3477

Here is some good info comparing np203, np205, np208, np241c. The New Process transfer cases I am partially familiar with.

[carnuck]

If you dig around junkyards, I have been told that some 4 cyl and 2.8 V6 S10s and Blazers got a 23 spline output. I haven't seen one myself, but it should work with a Dodge NP208 which is mirror imaged to the Jeep one.

[councilxvb32]

very good

[derf]

If you dig around junkyards, I have been told that some 4 cyl and 2.8 V6 S10s and Blazers got a 23 spline output. I haven't seen one myself, but it should work with a Dodge NP208 which is mirror imaged to the Jeep one.

That doesn't help when the 700R4 has a 27 spline output and the bolt pattern is rotated substantially compared to the Dodge/Jeep pattern.

Best choice for a GM transmission is an NP208 or passenger side drop NP241 from a Chevy/GMC pickup or K5 Blazer.