Author Topic: NP203 or NP208  (Read 9524 times)

Offline blazing816

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NP203 or NP208
« on: January 16, 2014, 12:48:30 pm »
Okay I know there is a lot of talk about converting a np203 full time, into part-time. My new project which will tow a travel trailer couple times a year, will have half ton springs, crate 350, carb and 700r4. I am picking up a set of 3/4 ton axles (dana 44 and corporate 14 FF) from a 78-79 truck. It had a np203 full time transfer case, and I already have a 700r4 with a np208 and I want the 700r4 for the overdrive because most of the time I will not be towing and driving country/highway speeds.

So I guess what I am looking for is would it be better to run the np208 and change the axle to manual locking hubs (or is it more then that)??
Or would it be better to get the conversion kit for the np203 and axles??

The reason I ask is I know the np203 is cast iron, where the np208 is not (its lighter). I will not be doing any wheeling, mostly a winter/snow rig, and towing of camper few times a year, so do not think I need a cast iron one, but looking for somewhat "bullet proof" mechanics (I am looking for the one that has better "inners"). Also would the np203 attach to my 87ish 700r4?? or would I need an adapter??

Thanks for replies in advance I am looking at the axles this weekend and if the np203 will be better I am going to see if he will sell me that in a package deal.
« Last Edit: January 16, 2014, 12:50:41 pm by blazing816 »
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Offline dvdswan

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Re: NP203 or NP208
« Reply #1 on: January 16, 2014, 01:24:54 pm »
well, I see this as you have a couple of options...

1) use the 700r4 and 208 as you already have them, the 208 would be ok with but it is know to be weak and know to stretch the chain.
2) get an adapter to mount the 203 to the 700r4 and buy a 2wd conversion kit, this would work as well but 203 again has a chain and it will stretch, plus its 200+ lbs of weight but its very strong.
3) get a 241 t/case, stronger than the 208 but you have to buy one
4) get a 205 t/case, strong, all gear, and you have to buy one.

If it were me, I'd go with #1 just because you have it, freshen them up if needed.  your not doing any hard wheeling so the chain stretching wont really be in play.  down the road look for a 241 out of a 90-91 sub or cc

Offline Engineer

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Re: NP203 or NP208
« Reply #2 on: January 16, 2014, 05:19:47 pm »
I'm thinking stay with the 208.

Put the lock outs from your 1/2ton axles in the 3/4ton axles and drive it.

The 203 is a boat anchor and if it has been run as a full time for 30 years it will most likely have a stretched chain.
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Offline bake74

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Re: NP203 or NP208
« Reply #3 on: January 16, 2014, 08:25:47 pm »
I'm thinking stay with the 208.

Put the lock outs from your 1/2ton axles in the 3/4ton axles and drive it.

The 203 is a boat anchor and if it has been run as a full time for 30 years it will most likely have a stretched chain.

     You never said it you will ever be towing in 4wd ?  The 203 will make you suck way more gas anyway, and the 208 is a good case as long as you don't abuse it.
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Offline pholliday1

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Re: NP203 or NP208
« Reply #4 on: January 16, 2014, 10:27:10 pm »
The 208 is a great case, at least the military thinks so. Not heavy duty enough? A lot of GI's might beg to differ the 208 comes standard on the military full size 1 1/4 ton full size square bodies and there 3/4 ton full size blazer counterpart behind the 6.2l Diesel engine. I've run 208's for over 20 years. Rebuilding them is fairly easy with the shift fork and chain being the major wear items. But the majority of issues stem from not keeping the proper level of ATF fluid in them. My guess is depending on your Current driveshafts you need to double check the lengths for compatibility. You stated its not really an issue but the 208 does have a lower 4lo gear than the 203. Good luck with whatever you decide.
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Offline Irish_Alley

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Re: NP203 or NP208
« Reply #5 on: January 16, 2014, 10:55:33 pm »
like whats being said keep the 208. one of our posters on here has one on his plow truck. and they are both chain driven so thats not something to compare them too. the 203 and 205 are sought after more for muddling/off road or having a over kill transfer case.
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Offline blazing816

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Re: NP203 or NP208
« Reply #6 on: January 17, 2014, 08:54:43 am »
Thanks all, I was pretty sure I was going to stick with the 208 and just put lockouts on the 3/4ton axles, I am mostly getting the 3/4ton axles because I am getting them for about the same/lower price that it would cost me to buy a gears for my 1/2ton to make it 3.73 or 4.10 (plus supposaly the axles have never been plowed with or mudded with, so suppose to be in great condition). Plus I have the drive-shafts that go with the 700r4 and 208, so shouldn't have to worry about length.

And no I would not be towing in 4x4, that's mostly for the bad snow days around here.
« Last Edit: January 17, 2014, 08:59:55 am by blazing816 »
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Offline Irish_Alley

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Re: NP203 or NP208
« Reply #7 on: January 17, 2014, 10:59:34 pm »
to give you an ideal on axle prices. i have picked up matching axles (¾ton 4.10) at the junk yard for $200
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Offline blazing816

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Re: NP203 or NP208
« Reply #8 on: January 22, 2014, 10:38:58 am »
Sweet thanks Irish....I got both axles 3/4ton with 4.10 for $200 with rims and roller tires (since my six lugs wont fit, it will help get it around the yard). And it has been in family since new and has never been mudded with or plowed with (as I am told).

It was AWESOME the guy had two hangers (yes airplane hangers) full of old stuff, all indoors in great condition. He had a mint firebird, mint caddy, had a 70s motorhome with 34,000 original miles been store indoors its whole life so it looks brand new. Had a 80s c60 mid-duty truck in perfect condition look like it had never been used as a "truck". Had a 60s c40/c50 also that was in good condition for the year. It was crazy.

And he had a 1984 K20 quad shock truck there with no rust. original fenders with stickers on them still, original bottle jack on holder on fender. supposedly never had panels replaced on it and had what he believed to be around 40,000 original miles. I did really check it for body work, I was just amazed at the crap this guy had (even had a old original singer sewing machine, it was like a pickers dream).
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1988 Chevy R20 Scottsdale Crew Cab (350/TH400/4.56)