NP203 Conversion Kits

[skink4president]

I've got a 1973 K5 with an NP203 transfer case. It's a daily driver and of course the gas mileage is horrific . As much as I like the fulltime 4wd I'd like to make the conversion.

I'v seen references in the forum to two Mile Marker kits. One's refered to as the "cheap conversion" and the other the "good conversion". What's the difference? Any other suggestions regarding this project? Different kits? Different companies? Different transfer case? I'd like to keep it as stock as possible.

Thanks again.

 

[Cricket]

The cheap kits is a set of 4 blocks that replace your output shaft spider gears.

The good kit is a complete solid shaft that replaces both your current shaft and spider gears.

An optional case is the NP-205, all gears no chain.

 

[conoverbandit]

Don't know, but I've heard that doing that conversion only nets you about 1-2 MPG more than what you're getting now. I heard it here somewhere. Mine is full time also,I had thought briefy about doing this, but I opt to keep mine FT. just my $.02.

 

[RedBrute]

I put the "cheap" kit in my son's '79 K10 last fall following the writeup on this site by Grimreaper. That was about 5,000 miles ago, he drives home from school in Connecticut every other weekend. I'd say the kit more than paid for itself in that time in fuel savings. The cheap kit is suitable for street use and the better kit is best for offroading in my opinion.

 

[carolina k-5]

i got a rebuilt 203 with the "good conversion kit" installed from t-case express. no problems so far.

 

[southernspeed]

There's a write up in the 'tech articles' section worth a read.

 

[blazinzuk]

If you use the "cheap kit" there are two housings the spider gears are in (thats what they look like they are the gears the kit replaces) one is thin and the shafts are held in with roll pins and the other looks damn near solid and is held together with bolts. You should have the thicker one but if you don't it is worth it to find one.