Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

manual tranny+np203 combo?

Discussion in 'The Garage' started by the general, Mar 5, 2006.

  1. the general

    the general Registered Member

    Joined:
    Oct 2, 2004
    Posts:
    96
    Likes Received:
    0
    Location:
    prinsenbeek(the Netherlands)
    i have a few questions:crazy: : is there a manual+np203 combo? what sort of gearbox is in front of that?( i now the shiftpatron is L,1,2,3 and of course backwards) a guy is asking about 350 dollars for it ) 300 Euro,s(i live in The Netherlands) its complete with the crossmember, gearshifter,flywheel, complete with pedal and cable and transfercase(np 203?) will this fitt behind my actuel combination 383 stroker,th350,np203? and if not what would i need?( the 383 stroker has a 400 flexplate or not?):bow:

    regards Patrick.
     
  2. 1979jimmy350

    1979jimmy350 1/2 ton status

    Joined:
    Mar 24, 2004
    Posts:
    3,069
    Likes Received:
    0
    Location:
    Ann Arbor Mi
    yes there is a manual 203 combo they were only used for one year and are pretty rare
     
  3. steve_kibbe

    steve_kibbe 1/2 ton status

    Joined:
    Feb 4, 2004
    Posts:
    2,895
    Likes Received:
    2
    Location:
    Spartanburg, SC
    It is prolly a sm465/np203 combo.

    Sounds like everything is there you will need.
     
  4. the general

    the general Registered Member

    Joined:
    Oct 2, 2004
    Posts:
    96
    Likes Received:
    0
    Location:
    prinsenbeek(the Netherlands)
    okay guys thanks for the reaction butt, will this combo fitt?(because of the stroker engine with the 400 flexplate now) i,m asking you guys this because parts( i,m the Netherlands) are not laying on the floor(they are a real dissaster to get here) and how about the price ?
     
  5. steve_kibbe

    steve_kibbe 1/2 ton status

    Joined:
    Feb 4, 2004
    Posts:
    2,895
    Likes Received:
    2
    Location:
    Spartanburg, SC
    The price doesn't seem to bad if its already there. You will need a 400 sbc flywheel, not a 350.
     
  6. southernspeed

    southernspeed 1/2 ton status GMOTM Winner

    Joined:
    Dec 24, 2003
    Posts:
    4,395
    Likes Received:
    50
    Location:
    VA
    I had that set up and it was HORRIBLE!!! I'd stay clear of it if I were you. A 205 would be much better.
     
  7. steve_kibbe

    steve_kibbe 1/2 ton status

    Joined:
    Feb 4, 2004
    Posts:
    2,895
    Likes Received:
    2
    Location:
    Spartanburg, SC
    It would be great for a doubler though:D
     
  8. 79k20350

    79k20350 3/4 ton status

    Joined:
    Nov 22, 2004
    Posts:
    7,757
    Likes Received:
    1
    Location:
    Ct
    all depends on what your doing with it. id pay 350 for it no problem. its a rare combo and is a great way to do a doubler:D
     
  9. the general

    the general Registered Member

    Joined:
    Oct 2, 2004
    Posts:
    96
    Likes Received:
    0
    Location:
    prinsenbeek(the Netherlands)
    William, you said the combo was build only one year? what year was that, do you now that? is it a 10,11,or12 inch clutch diameter?and Mister Southernspeed why was that a horrible combo? is the SM 465 bad or is it the 203 (in my case a parttime,shaftkitt) that is bad?, will any NP 203 fitt behind that SM 465?. i now guys these are a lott of questions but i wanne be sure of everything!!!
     
  10. onetonbb74

    onetonbb74 1/2 ton status

    Joined:
    Dec 1, 2005
    Posts:
    2,083
    Likes Received:
    2
    Location:
    Campbell, CA
    The transfercase will only bolt to the adapter that came with it or any other setup that uses the same transmission/transfercase setup. NO a 203 cant just bolt onto any other tranny combo with a 203 behind it. Input gears need to be swapped to do this. The 465/203 i believe is 1973/4 stuff. To use this combo for what your looking to do you will need to get a 400sbc flexplate. Then you need a input gear (27 spline th350/203) and adapter for a th350/203. Next is crossmember, need a 203 Xmember or modify the one you have to fit. I would find a th350/203 combo to make it cheaper and easier (this is the most common tranny/case if found out there). The sm465/203 combo is expensive because its rare and people want to use it for a doubler with a sm465/203/205 setup. You can always pick it up and sell the input gear, adapter, or range box for $, thats what people want/need. If you grab it, then use the whole thing, not worth using the 203 only. my .02
     
  11. steve_kibbe

    steve_kibbe 1/2 ton status

    Joined:
    Feb 4, 2004
    Posts:
    2,895
    Likes Received:
    2
    Location:
    Spartanburg, SC
    The "bad" is the np 203, b/c its a chain driven t-case.

    I believe the sm465 uses a 11 or 12 in clutch.

    Not any np 203 will fit behind, unless you change the input shaft.

    The sm465 is a great transmission!!
     
  12. the general

    the general Registered Member

    Joined:
    Oct 2, 2004
    Posts:
    96
    Likes Received:
    0
    Location:
    prinsenbeek(the Netherlands)
    thanks for the reaction bb74 ,i now have a parttime th 350/np203 combo under my 75 k5. but i want tranny brake control going downhill with a 5900 pound truck ,and if it falls out i,ve got no brakes!,and you can,t drivestart an autotranny isn,t it?. so this i why i want to swap the hole thing! in manual(95% is onroad use ) are there more things i need too now about the SM465/NP 203 combo? where too buy parts for the sm465 and 203?
     
  13. the general

    the general Registered Member

    Joined:
    Oct 2, 2004
    Posts:
    96
    Likes Received:
    0
    Location:
    prinsenbeek(the Netherlands)
    why is a chain bad Steve? it is not as strong as205 gears but it is quieter than a np205 and if well maintained its almost that good i think (sorry for the bad language) its not easy too talk technical in a differrent language.
     
  14. 1967k10

    1967k10 1/2 ton status

    Joined:
    Nov 21, 2005
    Posts:
    1,728
    Likes Received:
    0
    Location:
    Nebraska looking for D60's
    The 203's chail will break/stretch under lots of power.I've been looking for a 465/203 combo so I can do a 465/203/205 Doubler but I may just settle for a 465/205. It's a rare combo no doubt.I'd grab it and resell it but beings where you live it may not be as easy to sell stuff where you live as it is here. Just my .02
     
  15. b454rat

    b454rat 1/2 ton status Premium Member

    Joined:
    Jan 21, 2003
    Posts:
    3,009
    Likes Received:
    7
    Location:
    Binghamton NY
    How much are these worth?? I know where there is one sitting, and gonna check for more this weekend at another yard.....
     
  16. southernspeed

    southernspeed 1/2 ton status GMOTM Winner

    Joined:
    Dec 24, 2003
    Posts:
    4,395
    Likes Received:
    50
    Location:
    VA
    For normal driving it was really horrible. I put it down to slop in the chain but it was really messy changing gears like you were taking up loads of slack every time. Behind the th350 i really like the 203 especially in really tricky slick conditions where you can run it in 4 unlocked.
    But behind a manual?......no thankyou, not for me!
     
  17. tarussell

    tarussell 1/2 ton status

    Joined:
    Dec 28, 2002
    Posts:
    1,354
    Likes Received:
    0
    Location:
    Bagdad , FL
    SouthernSpeed - is right on about the 465 mated to a 203 case that is still full-time . Full-time opperation with an automatic tranny is real nice but the slop and driving characteristics of a full-time case with a manual tranny made for a sloppy driving experience to say the least.

    Those that convert to part-time , or use as a "Doubler" do not have that slop and therefore it is a desirable set up.
    According to the GM parts manuals the 465/203 combo was offered for three years 1974 -1975 and 1976 . I have seen applications for 1974 & 1975 but never a 1976 model. I think GM just phased the option out when sales just did not happen like they thought they would therefore 1974 seems to be the year most often seen.

    Tom
     
  18. 72chevydsl

    72chevydsl Registered Member

    Joined:
    Jan 22, 2006
    Posts:
    12
    Likes Received:
    0
    Location:
    modesto CA
    This topic interests me so this will be my first post here. I have ran the 203 behind a standard and auto tranny. I loved them both. I guess I dont Know what "slop" you guys are talking about, my standard tranny with 203 ran the same as my auto with 203. I know you all will think I am crazy but I replaced my 205 for a 203 in my 72. I just like the full time 4WD, you never lock in the hubs and I hardly ever have to shift into lock. I am running my 203 behind a cummins 5.9 with probably 400-450 torque, I dont think they are as weak as some people think. I also get 15-20 mpg on the hiway with this set up. Just my 02. I wish they still made full time Tcases.
     
  19. Zeus33rd

    Zeus33rd Smarter than you GMOTM Winner

    Joined:
    Mar 14, 2002
    Posts:
    7,324
    Likes Received:
    9
    Location:
    Grass Valley, CA
    If you want to swap out your th350/203 combo for the 465/203 combo, there some issues to contend with. You don't need to swap input shafts/output safts. Just yank your 350/203 combo, and stick the 465/203 combo back in. You need a flywheel for your motor, NOT a flexplate. You'll need a pilot bearing. You'll need a clutch, 12". You'll need the clutch pedal assembly from a manual trans truck. You'll need all the linkage from the pedals down to the tranny. You'll need the bracket on the frame from a manual trans truck that the clutch rod and z-bar mount too. It's riveted on from the factory, so it might be easier to fabricate one. If you're planning on a hydralic clutch, you'll need all the corisponding parts from a hydralic clutch equiped truck. Your crossmember will work, you'll just have to redrill the mounting holes in the frame. You have to drop the steering column to mount the new brake/clutch pedal assembly. You'll need to either cut a hole on the floor for the shifter, or get the tranny tunnel cover from a manual trans truck. You'll probably need to get your driveshafts lengthened/shortened.

    As far as the 203 being weak, thats absolutley NOT true. The chain in those things is like 5" wide. If a 203 is in good shape, they're pretty hard to blow up. They just get a bad rap because every 203 out there is atleast 26 years old, with a bazillion hard miles, and prolly never been maintained. Of course the chain stretches, and can get loose enough to break...but if it breaks it not because it's inherently weak. It's because it's worn out. Worn out stuff always breaks easily. So if your really up to all the work involved in this swap, go for it.

    Before anyone starts sqwakin at me about any of the stuff I just said, I've done the exact same swap this guy wants to do. I ran a th350/203 combo in my 76 for the first year or so, swapped to a 402 big block, an the th350 died within 2 weeks. Swapped in a TH400/208 (another chain driven t-case) next, and broke the tranny case right next to the adapter. Picked up a 465/203 combo from a buddy for a $100 and have been running it ever since. I'll never have another suto trans in a wheelin rig again. The 203 lived behind the 402 big block for another year or so with no problems. The 402 was no slouch either...I'd guess right around 350hp. And I didn't baby it, that 203 took a beating. Now my rig runs a bone stock goodwrench 350, the same 465/203, but with a doubler behind it now.

    Have fun with your swap if you decide to do it...Just be warned, its ALOT of work. And time. :wink1:
     
  20. steve_kibbe

    steve_kibbe 1/2 ton status

    Joined:
    Feb 4, 2004
    Posts:
    2,895
    Likes Received:
    2
    Location:
    Spartanburg, SC
    I don't think they are as rare as some say, A friend of mine got one for $75 off ebay:o
     

Share This Page