Author Topic: Part Time Kit for NP203  (Read 591 times)

Offline JohnnyPopper

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Part Time Kit for NP203
« on: January 14, 2019, 03:18:19 PM »
I bought a used Mile Marker 501 kit from a Truck recycling here in town, good guys, finally had them install it.

Started making loud racking noise in the transfer case, back into it.

Seems the kit came with the lockers for the differential but also has a radial roller thrust bearing spacer  that keeps the front axle from engaging while in 2x4.

The tech had never seen anything like that, so didn't think to install them, thus the racking noise under load.

 'CK5.COM has a write up where they illustrate the install and sure enough, they are needed.

Found some that fit, and she is running really good, It feels like I shed 500 pounds of steel!

Also found a former mechanic who had MM Supreme Locking hubs online, so she's styling.

He advised running it in 4x4 at periodic times to circulate oil into the rear tail stock. I'll do that by shifting into 4x, but not locking the hubs.

Only wish I had don't this sooner...  ;)



1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction