I know nothing about 4x4's ....can you tell what Ive got?

[72freak]

Any help would be great.......I am going to put lock outs on it and I was told with one of the cases you also had to do something inside the case along with the hubs........can you tell what I have? Do I need to change anything else?
Its in a 72 but I dont know if its original to the truck. Hi,Hi lock, neutral, low, low lock.

[jamie72]

looks like a np203 full time 4x4 case.not factory. there is a kit you can buy to be able to disingage the full time 4x4 option.
btw nice truck..

[72freak]

Originally Posted by jamie72

looks like a np203 full time 4x4 case.not factory. there is a kit you can buy to be able to disingage the full time 4x4 option.
btw nice truck..

Is the 203 the one you have to put something in the case itself...or will just the hubs need to be added?..

It is definatly all time 4x4.

Any links to a recomended 'kit' source would be appreciated

[bouncytruck]

I can't tell in the picture if it has a small round access panel between the output shaft and the large round cover. It looks like an NP203 (so is the shift pattern) but if it has the access cover, it's a NP205,

This is an NP205;


Also, the shifter pattern is different on a NP205 vs an NP203;

NP203


NP205


The NP205 is a gear driven, part-time 4wd case and would be stock for that truck. The NP203 is a full-time, chain driven case produced for later generation Chevy trucks. Mile Marker makes conversion kits to make them part time, but if you do that, you do need to put it into 4wd on occasion because they use the chain to fling lubricant inside the case.

More about the two - http://www.chuckschevytruckpages.com/drivetrains.html

[72freak]

few more

[special-K]

Yeah,it`s the 203 and you have full-time 4wd,as it is right now.Check with Milemarker or...who else these days??

[72BlckButy]

I can tell you what you have..... one sweet rig!!!!

[old Chevy guy]

If you put on lockout hubs and unlock them without doing that conversion to the transfer case the truck wont move at all.Saw a couple of guys do that.

[jeffspower]

Yep it's a 203. Not sure who all makes the kit anymore. It's pretty easy to do- only the rear output housing needs removed to do it. It involves removing the spider gears & putting a "lock" in. Some kits had four locks to replace the four spider gears, others had a one piece ring. try to find the one piece style. They seem to "clunk" less on accel/decel. Proper shimming is important & described in the instructions.

One thing to be careful of- needle bearings. They can fall out everywhere when you tear into it, and fall into the case. 203's have over 100 of them IIRC.