Manual hubs on 203 without part time conversion

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dhenderz

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Hi, 1st post. Purchased 77 K10 that I am doing a frame off resto on. Found out from original owner that manual locking hubs were installed to save on fuel, but no conversion was done to the NP203. He would just run the TC in high-lock to achieve 2WD (RWD) high for normal use. I have read this will lead to some nasty wear/tear on the internals of the 203. I was already planning to rebuild it anyway, but what should I be looking for in terms of worn items that will likely need extra attention?
 

Rusty Nail

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Seems to me that running in 4H is effectively 1 wheel drive and I fail to see how "some nasty wear/tear on the internals" is your reality.
That's pretty funny - manual locking hubs but still running 4H?
Complete waste of money! 100% no change. Never even saw the 0.33 mpg the locking hubs would have saved him had he ran in 4L, like a man.

You speak only of exercising futility.
Forgetaboutit!

Welcome to the site.
 

Christian Nelson

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I ran locking hubs on a 203, and they did help with not feeling the differential switching from front to back, and torquing your steering wheel like the full time 4x4's always do. I don't know how much better fuel mileage was, but it sure handled better on the highway. You need to run it in "HI Lock" for this to work, or you'll just spinn your front drive shaft and not go anywhere when your locking hubs are set to "free" I was very happy with how locking hubs worked on my old truck, would do it again, if I got another full time 4x4 truck.
 

Goldie Driver

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Funny - I always felt like my full time '77 Sub handled better as the front helped pull you through corners ...

Mileage wise I don't remember- probably 9 or 10 MPG on the highway.

My current '80 part timer has gotten a best of like 11.5 on the highway, so not much of a difference and that may be due to the 350c tranny - who knows.

Easier to pull a full time "hub" apart versus a manual hub ...

:D
 

Christian Nelson

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Funny - I always felt like my full time '77 Sub handled better as the front helped pull you through corners ...

Mileage wise I don't remember- probably 9 or 10 MPG on the highway.

My current '80 part timer has gotten a best of like 11.5 on the highway, so not much of a difference and that may be due to the 350c tranny - who knows.

Easier to pull a full time "hub" apart versus a manual hub ...

:D


For sure, I always liked to have the option to unlock them, or lock them in. REALLY nice to run on the freeway with the hubs locked in, with transfer case in "HI", and have that nice gription that gives, without wrecking stuff like running in regular 4x4 at speed in winter weather.. My old truck had 36" buckshot mudders, and the steering torque was bad when on dry pavement, so I also liked to be able to throw transfer case into HI Lock and free the front hubs. My truck used to get around 14 mpg, with a 350/350 3.75 gears with 36" tires. If I didn't hit the gas pedal alot, lol.. Around town, it got less, but on the freeway, it actually wasn't that bad at all.
 

MrMarty51

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I had gone through the rebuild of a 203 after part time hubs had been installed.
Inside the T~Case there is a small differential and spider gears, just like in a differential, running part time hubs will destroy that differential. Best to lock in the hubs and run it that way until a part time kit can be had and installed. I did a part time kit on My 78 K20 and it helped a lot on the front wheels not jumping when on hard pack or asphalt and the steer wheel cranked.
 

idahovette

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I have had a parttime kit in my 75K20 since the beginning(15K now 165K). No problems so far (knock on wood). Serviced regularly and has never had anything but 10/40 motor oil in it and a little higher level than stock. I have heard that it is hard or impossible to find replacement chains for these. Any body know for sure??
 

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No additional wear occurs from running in HI lock with hubs unlocked. That is like saying your differential gets worn out when both wheels are spinning at exactly the same speed. Hi LOCK locks the differential, so that it actuall wears the little spider gears even less than normal use.

In fact, installing a part time kit on the 203 causes lack of oiling to certain bearings if you rarely use the 4x4..

Also, you lose the ability to drive at high speed in HI with the hubs locked in, during slippery conditions, which is REALLY awesome.

I will never understand why anyone would ever install a part time kit on a 203. GEt a 208, or 205 , or some other transfer case, it's not like they are super rare these days. Don't wreck a 203 by turning it into a really poor performing 208..

Nothing is harmed by running in HI LOCK with hubs unlocked.
 

dhenderz

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Thanks for the quick replies. At this point I am seriously considering just taking it back to stock setup (full time 4x4 like from the factory). Fuel savings, whatever that may or may not actually be, is really not a concern. Once restored this truck won't be a daily driver nor driven hard off road. Just a fun truck for occasional drives. So I am thinking just put the truck back to stock and not worry about it.

Thoughts?
 

dhenderz

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I need to buy new hubs regardless. The current ones are totally shot, can't rotate them lock/unlock. Truck sat outside in a field for many years
 

K201979

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I see. Id still go with lockouts(i did in fact) if it were me. As long as it wasnt way cheaper to go back stock. I payed like $100 for warn lockouts with metal dial just fyi.
 

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I'm a big fan of not second guessing the engineers. As long as it isn't some known major shortcoming and you're not putting a million miles on it, leaving it the way it came from the factory is usually your best bet for reliability and longevity.
 

idahovette

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In fact, installing a part time kit on the 203 causes lack of oiling to certain bearings if you rarely use the 4x4..
I call ********, at about 150K and not having any oiling problems!! There is a LOT of splash lubrication going on inside this case as long as you keep the level up
 

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