transfer case options

[BIG CHEVY]

My 203 was leaking. I decided to have a little peek inside so i took the whole plate off. My chain was very loose. Question 1 is......can i tighten this or buy a new one and put it on myself? Question 2.......what cases will bolt in its place without modification? The case is very good. Strong.....takes a beating......shifts beautifully without problem.. The 203 life has been good to me. But if i eventually have to get a new one i need to know my options. Has to bolt on my 350 trans. Any takers?

[BIG CHEVY]

was certain this was an easy question.....

[zieg85]

I am no 4x4 expert but someone will eventually chime in, be patient.  The mosquitoes are keeping me in from working on stuff or else I would be playing outside on one of my many projects as a lot of the members are doing.

[beastie_3]

no i dont think you can tighten it.

yes you can replace it. how hard is it? dunno

do you have a manual, factory would be best.

[fitz]

shifts beautifully without problem.. The 203 life has been good to me.

If the 203 has treated you well I wouldn't be in a hurry to replace it. I've never replaced the chain in 1 myself but I can't see a tranny shop charging more than a few hours labor to go through it. Off the top of my head I would say you could have it completely gone through for about $500, maybee less.
If it has survived in the truck for over 30 years I would hang onto it. 

[BIG CHEVY]

Yeah....im gonna ride it till it breaks. But id like replacement things. Might look into buying parts trucks. A wise man knows before he buys which items will fit his truck. Like a 205. If i found a p truck with a 205 and got it home....thought i did good.....but wont fit. That would be heartbreaking. Do all t cases fit the same per case auto or stick? I got a 350 trans. Would a 203 out of a stick fit all the same? Do they all fit the standard crossmember regardless of 203....205....208....? Queztions like that are really what im after.

[Cabcorner]

     I bought a np205 32 spline with shifter and adapter for my 85 K20 then found out i needed a longer tailshaft for my tranny(turbo 400 4x4 's had 3 tailshaft lengths).The turbo 350s were all 27 spline  ,the sm465 had 2 versions ,the early ones were 10 spline and the later ones were 32 spline. The best bet is to find a complete donor truck,do your home work I wish I had

[thirsty]

Autos and sticks have different splines. At least th350 and sticks do I found out. I would replace your chain if you are happy with the 203 before something happens.
You can do anything a shop can do if you can read. If they sell the parts they are replacable. If someone else can do it you can too.

[jdl71]

At the least you'll need a slip yoke eliminator for the rear. If the 205 is from behind a TH350 then it should bolt in. Otherwise you may need a different output shaft and/or adapter to bolt it to the trans. As for the cross member, you can use a 205 cross member with a 203, but not vice versa:

http://coloradok5.com/forums/showthread.php?t=108220

How "loose" is the chain? Are you having trouble with it slipping or did it just appear to be loose to you? IMO the 203 gets an undeserved bad rap. It's got a couple of advantages in that you get a 2wd low, as well as not having to fool with hubs. If it's fuel mileage you're concerned with, buy an s-10. These trucks are not going to be gas misers no matter what you do to them. They do make a part time kit for this case and you can add lock out hubs if you so choose but personally if it works I'd just keep it. I do have a FSM if you choose to rebuild it or change the chain I'd be happy to scan the pages and send them to you.

[beastie_3]

you should scan the pages anyways and post them in the tech section

[jdl71]

you should scan the pages anyways and post them in the tech section

The whole manual or just the t-case section? That's a lot of scanning to do the whole thing. Plus there's a unit repair manual that deals with rebuilding individual components-engine, trans, t-case, power steering pump, a/c compressor, etc. I'm glad to scan something if someone needs it, but I'd be there for a couple of days scanning both books. 

[BIG CHEVY]

scan if you want (what u want) like beastie said. we all appreciate anything. but im not gonna tear it down unless i hit a problem. but thanks for the info....those tidbits are exactly what im after. knowledge. i could push the chain in the long stretch of the chain out at least to my first knuckle. i thought that was far. but its always worked great. on saturdays i usually read this forum and go out and check anything i can relate to reading. truth is......i love to learn. and now i know to only buy cases that came from automatics. and spline counts. these are things i cant just walk outside and check. if someone had a cheap 203 i could pick up for a spare i would have bought it. even behind a manual. wish i had more tidbits.......

[jdl71]

Someone correct me if I'm wrong, but I don't think you'll find a 203 behind a manual.

[Cabcorner]

Although rare , the 203 was mated to the sm465 in 73-74?I saw this set up on an old blazer.I just picked up a clean rust free cross member for my 205 swap complete with  203 adapter
will it work?

[DustyRusty]

The 203 was first offered behind the SM 465 in '74 trucks only.  After that 203s were behind automatics.

I agree that the 203 has got a bad rap.  It is a strong t-case.  If you swap to any part time t-case you will likely have negligible mileage gains over the 203. 

Rusty