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Manual tranismition with a NP203 T-case on a 77 k10? is it possible?

  
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Manual tranismition with a NP203 T-case on a 77 k10? is it possible?

 
kainhall kainhall
V-6 Camaros rule! | Posts: 38 | Joined: 05/10
Posted: 04/29/11
08:30 PM

basicly the title.... it has the stock 400 engine (jsut got running right...fucking chery!) and hte stock full tiem NP302 T-case on my 77' chevy k10 silverado.

i rebuilt the transmition a while ago and it works fine and all, but the shifts from 1 to 2 are kinda slow and im thinking thats putting a lot of friction on thwos clutch plates. and i have always liked Manual Trannys like this 70' dodge i drove threw rush hour trafic in the twin citys...and had it randomly die on a interstate! i like the abilty to select any gear, engine beaking and all that otehr good stuff (MPG improvment with that full time four!!)....and sence im ADHD i gives me somthing to play with!


but, is it possible to mount the 4 speed we have out at the shop (unknown slpine count and model number...i could find out however) to the 203.


i heave heard some 203s and a 10 slpine, but theres 32 spline ETC and the same with the tranny. and waht about teh spacing between the T-case and the tranny? would you need to make/buy a...like hollow tube to fit in between?

and i know all the work its going to take (mounting the clutch pedal, crossmembers, just moving that 203 cast iron beast!) and im ready to do it for a summer project.


anyway, how and how mutch!
thanks


P.S. full tiem four+400SBC+a record snow fall of 108 inches = never used high or low lok!  

tuffnuff tuffnuff
Moderator | Posts: 268 | Joined: 01/10
Posted: 04/30/11
09:54 AM

The truck 4 speed bolts right up to the NP 203 transfer case and the splines agree with the slip coupling that joins tranny and the 203.
Difficult to determine what will fit, until you know what you've got there.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

waynep7122 waynep7122
Everything in my driveway’s a Chevy | Posts: 556 | Joined: 08/09
Posted: 04/30/11
11:18 PM

i take it that you are not aware that there are a dozen truck magazines on this site also....

there are so many different ways to swap things around... i though i would head you in the right direction.

http://www.off-roadweb.com/tech/1005or_common_transfer_cases_guide_high_low_ranges/index.html

be sure to check the right side bar for additional articles...  

you can also use the search window from that magazine search for transfer case...  

chevelle83 chevelle83
I have an SS396 tatoo | Posts: 442 | Joined: 10/08
Posted: 05/02/11
11:01 AM

not too fast there tuff, first we need to identify which 4 speed he has.  

it could be the GM SM465, which I have never seen bolted to a NP203! from the factory.


or it could be an SM420, also I dont know of a transfer case that bolts to it, you see back in the day, before gm started using 4 speeds in 4x4 trucks, they came with a 3 speed on the column (saginaw)  and a dana 30 case.

  it was a good reliable setup but not brute strong like the later ones.


unless you build some kind of special adapter (serious fabrication)  I dont think this is gonna be easy, or even possible for you.  you would need a machine shop to make the parts.

to me you best option to get a 4speed,,,,,,,,,, is to just find an entire sm465 and np205 setup.    it will bolt right in and keep your current crossmember.

however the rear drive shaft will have to be longer because the np205 is shorter than a np203.  

chevelle83 chevelle83
I have an SS396 tatoo | Posts: 442 | Joined: 10/08
Posted: 05/02/11
11:11 AM

does the 4 speed you have look like this?
Images?Q=Tbn:And9gcqhdar7ws4nrm4htfynai1lijsxhnbtsrtwas7ydsv9qjbbsepu2g


or this?  this is the sm420
Images?Q=Tbn:And9gcq Pzmqv 9X8bfeztcrzuo3e Xuagxk2k Rbaycczegembtvvqy


as far as I can tell any transfer case adapters will be special made for the sm420

I found this pic with a special adapter
Images?Q=Tbn:And9gcsxyzsz94iqxrrt6 B8uh2ocnigkjxlqrv4s1nbnfmknwkotkjf&T=1  

tuffnuff tuffnuff
Moderator | Posts: 268 | Joined: 01/10
Posted: 05/02/11
08:15 PM

Icon Quotechevelle83:
not too fast there tuff, first we need to identify which 4 speed he has.  

it could be the GM SM465, which I have never seen bolted to a NP203! from the factory.


or it could be an SM420, also I dont know of a transfer case that bolts to it, you see back in the day, before gm started using 4 speeds in 4x4 trucks, they came with a 3 speed on the column (saginaw)  and a dana 30 case.

  it was a good reliable setup but not brute strong like the later ones.


unless you build some kind of special adapter (serious fabrication)  I dont think this is gonna be easy, or even possible for you.  you would need a machine shop to make the parts.

to me you best option to get a 4speed,,,,,,,,,, is to just find an entire sm465 and np205 setup.    it will bolt right in and keep your current crossmember.

however the rear drive shaft will have to be longer because the np205 is shorter than a np203.


I had a 78 GMC with a TH-350 that bagged it.,. a truck 4 gear bolted right up, but that was 30 some years ago and long before these newer 4 speeds came along.,. I did say, that he has to see what he's got, to determine IF it fits or not.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder