4x4 question

[pimperout]

i found a 79 chev truck at my cousings house which he said he would sell me for a pretty cheap price, so i went and had a look at it first thing i looked at was to see if it was a 4x4 bye the locking lugs. it didnt have locking lugs then i figured it sat wrong to be a 2wd so i looked underneath and sure enough it was a 4x4 of some sort. soo i asked why it had no locking lugs with a front diff, i thought mabe it had auto locking hubs aftermarket or somthing, but no he said its some sort of factory all wheel drive. just wondering if this is anactual factory option, how it works, and if its rare. thanks for taking the time to read all this i know its a long explainaion lol.

[Russell]

It is a full-time 4x4 truck. The front diff has what are called "Wheel Flanges" which basically lock the front wheels to the front axles full time, instead of being able to unlock or lock them as you please.

The truck will have an NP203 transfercase, its not a rare thing, nor is it particularly desirable, becuase you waste a lot of power and gas running 4x4 all the time, not to mention a loss in handling by having the front end locked in all the time.

Good news is that you can easily replace the transfercase with a part time case like an NP208, or NP205, or you can buy a kit to convert the NP203 over to a part time transfercase. You can remove the wheel flanges to install a set of locking hubs without any modifications to the diff as well, which I would reccomend doing, even if you don't do anything with the transfercase, as you'll be able to unlock the front end, and run it as a 2wd, even though the front diff will still be recieving power.

[72lb4x4]

In the mid to late 70's somebody decided full time 4-wheel drive was a good idea. It wasn't. Those trucks tended to eat front driveshafts and gas, or at least that's the impression I got back then.

Supposedly, the transfer case can be converted for not a lot of money and locking hubs added to make these trucks part time 4x4.

If I'm wrong, don't be shy of calling bull on me. I'd rather be educated painfully than continue to be ignorant...

[Roper]

The problem with converting a 203 to part time is that they dont get proper lubricant in 2 wheel drive. So if you confert one you have to run in 4 wheel drive every now and then to keep everything in the transfer case lubricated.
Also for extreme wheeling those heavy long 203 cases tend to break at the housing.
Much better to just go with a 205 or 208 TC. The 205 is the better of the two but 208 can be rebuilt for half the cost.
Anyway this is just what I have been told. I dont have first hand knowledge on the 203.

[74 shortbed 406]

The 208 tc has a better low range and is also lighter because of the aluminum case, it has been put in one tons so is strong enough for most people trucks. The 205 is stronger because it is gear driven and cast casing, this case is almost unbreakable( I have never seen a broken one). My old 81 k10 said to lock on four wheel and drive 1 mile a month to properly lubricate the front end and it had a 208. I have a habbit of once a month driving aroud my grandmas farm in 4x4 whether dry or wet just to rotate everything. Just personal opinion. The 203 has benefits just don't know any at the time. I would at least put the part time kit on it or try swapping the front to lockouts. Still will be turning the internals if only doing lockouts.

[msgross]

I had a 79 Blazer like that... I removed the front driveshaft in the summer, should have just installed locking hubs, takes about 30 minutes max to do it... My Blazer always got about 13mpg with a 4bbl and 350cid...

[pimperout]

ok cool thx for the info guys, i just talked to my cuzin today and he said "take the truck i dont need it" so im gonna get it on friday im just gonna kinda fix it up to be used as a mudding/hunting truck mabe lift it a bit and put knoby tires under it

[snj8198]

You might want to look a little deeper into this. I'm don't believe you can merely install lockout hubs and not put the partime conversion into the 203. The 203 works much like center differential when not locked in. When not locked the 203 transfers torque biasing it front and back. If you unlock the hubs in the front power will take the path of least resistance. My buddy did a hub swap only on a full time 4x4 some years back and came to me wondering why the truck got so sluggish. We found that the sluggishness immediately went away when we locked the 203 in. So with out the part time conversion installed the 203 acts like an open dif allowing your torque to spin out the unlocked front due to no resistance, much like an open dif spinning one wheel when it loses traction.
Hope I push you in the right direction! Congrats on your score! -steve

[stan79chevy]

snj8198 is correct. The inside of a 205 is like an open diff it sends power to the least resistance. If you put in manual hubs you'll have to run the transfer case in either hi-loc or lo-loc for it to send power to the rear wheels. I put manual hubs in mine it WILL save you some gas milage..it also makes it so you can turn in a parking lot. I would not waste the time or money putting a part time kit in the 203. Run the 203 until it breaks the rear off..or the chain breaks, then replace it with a 205. If your tempted to go with a 208 look at a 208 then a 205 in person not just pictures..208 is a tiny little aluminum chain drive unit...205 is a cast iron semi unbreakable unit.

stan

[pimperout]

all right thanks for that last bit of info i was just searching for some locking hubs that saves me some trouble. i dont think im gonna bother with it till the transfer case breaks or somthing its gonna be in 4x4 for most of its life with me any way. thanks for the info guys this place never fails to give me a good anwser and more

[Hoods69BadBowTie]

Go with the manual hubs you won't regret it.