205 vs 203

[Canadian 4X4]

I am looking into buying a 4x4 what is a better transfer case the NP205 or the NP203? This will be a street and off road truck. I would like the option of 2wd so i would put a part time kit into the 203.

[4x4orbust]

the 205 is, in my opinion, tougher than the 203. 

[malibu795]

the 205 is, in my opinion, tougher than the 203. 

tougher? in what way?
cast iron doesnt like to stretch
aftermarket off-roading options 205 has the 203 beat.. the gears arent the weak link the case is.

strenght.. look at todays allum chain drive t-case can be put through.. they can take the power fo a 1000+rwhp diesels roughly 1200-1500rwtg all day... mild hp 350sbc (300-350hp) can split a NP205

IMO biggest problem on the older chevy is the mis match gearing 4.09/4.10 or 4.11/4.1.. it wears out the center dif in the 203

reduction.. planetary(203) vs gear(205).....

power transfer... gear vs chain.  IMO back to what is holding the chain/gears are in... cast iron doesnt like tension/pulling loads. what do gears do when power is applied to them? then what does chains do?

what is the end result/goal for this rig? for a mainly DD either works. i would go for the 203.. if you plan on putign a doubler inthere you dont have to find a 203

im running a 203 currently behind my th400 and built 383sbc

[Canadian 4X4]

The trucks I am looking at is a 400/350/203 all its good for is the drive train and i would have to do a body swap
the other is a 350/350/203 with manual front hubs but i don't think it has the conversion done yet. i prefer the look of the 73-80 over the 81-87 and i know most of them came with the 203 i am not sure what year they changed transfer cases. it wont be my daily driver but it will definitely be driven on the street hopefully quite often in the summer and stored the winter. I know the 203 is chain driven and i have heard it takes a lot more hp to turn the 203 over the 205, i want the truck to be OK on fuel.
sorry about the novel and dumb questions just trying to learn some important stuff to inquire into my first purchase. This forum has been helpful and i feel i have learned alot thanks to everyone in advanced

[malibu795]

The trucks I am looking at is a 400/350/203 all its good for is the drive train and i would have to do a body swap
the other is a 350/350/203 with manual front hubs but i don't think it has the conversion done yet. i prefer the look of the 73-80 over the 81-87 and i know most of them came with the 203 i am not sure what year they changed transfer cases. it wont be my daily driver but it will definitely be driven on the street hopefully quite often in the summer and stored the winter. I know the 203 is chain driven and i have heard it takes a lot more hp to turn the 203 over the 205, i want the truck to be OK on fuel.
sorry about the novel and dumb questions just trying to learn some important stuff to inquire into my first purchase. This forum has been helpful and i feel i have learned alot thanks to everyone in advanced

fuel between the two 203 has more rotating mass then a 205..  hands down.
plus your driving the fron 100% of the time vs part tiem of the 205. part tiem conversion for the 203 would help that.

right now i see ~10 wiht my setup.

more like to find a 203 in the 73-80 then 81-87

[4x4orbust]

main reason why i see it as tougher is because of the gear drive instead of chain drive.   on the other hand, i am speaking from more of an offroad standpoint.   as far as cases being the weak point, yes they are, but it is tougher to break the case than it is to break the chain.   as i said,  it is in my opinion. 

[frickenbored]

I love my 203, its a super beefy transfer case.  Sure it has a chain but the chain its almost twice the size of any transfer case out there today.  My 203 is from 1976 and I'm pretty sure it had never been opened before.  A couple weeks ago I took it apart to do a part time conversion, the chain was still tight, there wasn't one metal shaving in the oil, and all the gears were in perfect shape.  In my opinion is a very realiable unit. 

Also you can take the stock shifter apart, set up a shifter for both forks and then have a transfer case that can shift into 2wd Lo for almost free.  The only down side I can see is that the 203 is HEAVY.  And its very akward to work with because of the size.  On the other hand I've never used a 205 or even known anyone whos used a 205.  Everyone I know has a 208.

[smitty77]

Also you can take the stock shifter apart, set up a shifter for both forks and then have a transfer case that can shift into 2wd Lo for almost free.  The only down side I can see is that the 203 is HEAVY.  And its very akward to work with because of the size.  On the other hand I've never used a 205 or even known anyone whos used a 205.  Everyone I know has a 208.

You can twin-stick a 205 as well, and it's gotta be just as heavy as the 203, or darn near it.  I muscled mine around myself and that sucker is heavy.  The 208 is a featherweight compared to it.

And while I agree the 205 is supposedly the stronger case due to being all-gear driven, I've seen lots of trucks run an awful long time behind a 203.  My grandfather had a '73 blazer that he bought new and drove it for 20+ years, towing a 18' camping trailer across the country a couple of times and never had a lick of trouble with that case.  When he had it converted to full time (sometime in the late 80s) the auto shop teacher that did the work (my grandfather was a carpentry teacher at a vocational school) said the internals were in perfect condition.

[frickenbored]

Also you can take the stock shifter apart, set up a shifter for both forks and then have a transfer case that can shift into 2wd Lo for almost free.  The only down side I can see is that the 203 is HEAVY.  And its very akward to work with because of the size.  On the other hand I've never used a 205 or even known anyone whos used a 205.  Everyone I know has a 208.

You can twin-stick a 205 as well, and it's gotta be just as heavy as the 203, or darn near it.  I muscled mine around myself and that sucker is heavy.  The 208 is a featherweight compared to it.

And while I agree the 205 is supposedly the stronger case due to being all-gear driven, I've seen lots of trucks run an awful long time behind a 203.  My grandfather had a '73 blazer that he bought new and drove it for 20+ years, towing a 18' camping trailer across the country a couple of times and never had a lick of trouble with that case.  When he had it converted to full time (sometime in the late 80s) the auto shop teacher that did the work (my grandfather was a carpentry teacher at a vocational school) said the internals were in perfect condition.

I couldn't lift my 203 at all when I had it out of my truck, thankfully I have a small front end loader that I moved it aroud with.  And yea the internals of a 203 almost never wear, other than the chain which even that lasts a heck of a long time.  I have a 76 203 and a 79 203, I've taken both of them apart thinking they could used a rebuild, wrong.  Both were in "like new" states.  I was very impressed.  New transfer cases don't even compare.  I blew up my 99 jimmy's np236 going mud bogging, I took it up a 60 degree hill and i heard a loud snap and then my 4wd didn't work.

[smitty77]

I couldn't lift my 203 at all when I had it out of my truck, thankfully I have a small front end loader that I moved it aroud with.

Yeah, when I say "muscle it around" there was no lifting involved by me.  I barely managed getting the TH400/NP205 combo onto a jack by myself by picking up one side, propping it on some cribbing, and repeating with the other side.  Heavy combo for sure.

Just picked up a SM465/NP205 combo and it's not any lighter.  Managed to get it out of my pickup by myself sliding it down some wooden ramps but I didn't move it much further after it was on solid ground.

[TimberJack]

In my opinion the 205 wins hands down.  I would leave the 203 in though untill I had a problem with it.  Chains stretch gears dont.  And you can rebuild a 205 with all seals and bearings in on kit for 200 $

[Chevalade]

Get a doubler kit and run both. I would run either....they are both very good t-cases.

[TimberJack]

He He doubler kit.  : They are all good till they break . I even run a 208 in one of my trucks. But if and when it breaks or bangs I got a couple of spare 205 s under the bench.  IF IT BREAKS BUILD IT BIGGER.

[Josh454]

203's are good for doublers and anchors.