Author Topic: np203 conversion  (Read 18018 times)

Offline Irish_Alley

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Re: np203 conversion
« Reply #15 on: November 02, 2013, 11:05:28 PM »
the whole point of the conversion kit is so you can drive the truck with only powering the rear wheels (helps mpgs and wear on front axle parts). like said if you keep the fronts unlocked and keep the tc in lock then you still can move but you still will be turning everything in the front axles making the hubs useless cause your still causing more drag on the drive train.
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Offline Cabcorner

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Re: np203 conversion
« Reply #16 on: November 03, 2013, 05:56:30 AM »
                    The thing to remember is that running  with the hubs unlocked and the transfer case in high lock will damage the internal coupler . It is better to lock the hubs and drive in High unlock .

Offline rewardedgamer

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Re: np203 conversion
« Reply #17 on: November 03, 2013, 06:57:00 AM »
the whole point of the conversion kit is so you can drive the truck with only powering the rear wheels (helps mpgs and wear on front axle parts). like said if you keep the fronts unlocked and keep the tc in lock then you still can move but you still will be turning everything in the front axles making the hubs useless cause your still causing more drag on the drive train.
is what cabcorner said true? about damaging the internal coupler?

Offline Jason S

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Re: np203 conversion
« Reply #18 on: November 03, 2013, 10:53:17 PM »
Quote
is what cabcorner said true? about damaging the internal coupler?

You run the risk of ruining a set of locking hubs with extended driving in Hi-Loc. 

Quote
where do i purchase a conversion
  Milemarker makes a fairly popular NP203 conversion kit and can be found at many auto supply stores, off-road shops, ebay, etc.

If you have hubs already, then according to the Milemarker website you would need Milemarker kit 501
http://milemarker.com/products/drive-train-products/conversion-kits-accessories

If you had not bought the hubs and you have a 1/2 ton or late '77-up 3/4 ton truck then you'd need Milemarker kit 502
http://www.summitracing.com/parts/mmk-502/overview/

I don't have any photos of the part-time conversion process, it really isn't overly complicated.  You might search the forum. 

Having two NP203 equipped trucks; in my opinion, either go for the whole conversion or keep it stock.  You save a little wear and tear by converting to part-time operation.

By keeping the NP203 as Full-Time and installing hubs, you can have 2WD function but there isn't any real gain by doing such.  The front axle parts will still be turning and wearing, as well as the hubs operating in a manner in which they were never designed to operate. 
1973 GMC K2500, Super Custom, Camper Special, 350, TH350, NP203, 4.10's
1974 Chevrolet K10, Custom Deluxe, 350, SM465, NP203, 3.73's

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Offline Cabcorner

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Re: np203 conversion
« Reply #19 on: November 04, 2013, 08:33:46 PM »

Offline Irish_Alley

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Re: np203 conversion
« Reply #20 on: November 06, 2013, 12:43:34 AM »
the only con about the conversion, i think i have ever heard or seen is about is about the seals drying out like rich was saying.

 not saying the coupler cant happen this is the first time that i can think of that i heard of this. and tell you the truth i dont see how. since in auto (pre conversion)the power is going to where ever it can front or rear slipping one way or the other. so with it locked its locked in place and not slipping one way or the other.

if your unlocked the front shaft will be spinning the same amount as the rear. but if the front is stuck in the mud it will get all the power and still be spinning. if you lock it the power will be split so you can get out. think of it like haven an open rear then putting a locker in it. its doing the same thing both side will be getting the power.

all the time i run with one hub locked and the other unlocked, so if i get stuck all i have to to is hop out and lock the drivers side and get going. guess what im saying is the front axles will all ways spin not at full speed but they will spin(i put my 465/205 in neutral and the front shaft was spinning the whole time. so this was turning one of the axle shafts) and i have only popped one hub and that was mudding.
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes