NP203 Help

[76/85 Truck]

Thanks for all who are reading! When I first started researching my 203, I thought maybe I had a model without the "lock" option. I crawled underneath it and i have 2 plates sticking out of the bottom of my shifter tower. when i have someone cycle it from Hi to Lo, the plate on the passenger side goes forward and back, and the plate on the drivers side TRIES to move more forward, but it looks to me like it is all the way forward it can go, so consequently, it won't go into "Lock". I took the linkage off the plate, and i can pull the linkage toward the front of the truck, and I hear a "clunk" and it goes in "Lock". So, I am guessing, my shifter mechanism is seized. But, it looks to me like the plate for the Lock is supposed to go back. Would someone please let me know which way the driver side plate moves when you put it in "Lock"? And if it indeed does move even more forward, should i just take the tower off and take it apart and lube it up? Thanks and sorry for the long post!!

[76/85 Truck]

Which way does this driver "plate" move when engaged in lock? It LOOKS like it already all the way forward, but the LOCK linkage only moves a small amount (about an inch toward the front of the truck) so does that plate or "Fork" go even further forward? THANKS a BUNCH!

[mokelife77]

what is the lock for?

[Adams74Chevy]

Originally Posted by mokelife77

what is the lock for?

The lock on NP203s is for low traction situations it sends the power evenly to the front and back, while when not in lock it will still send power to both front and back but if wheels start slipping more power goes those slipping.

I'm not much help on the linkage, but I plan on cleaning mine up and possiblely making it a twin stick to help alleveate the issues these shifter/linkage are known for.

[LONGHAIR]

It is a funny "clock works" inside there, but opening it up and cleaning/re-lubing helps a ton.
The lever that works the "hi and low" ranges moves foreward and backward from the neutral position. But, the lever that moves the "lock" only moves one way. This is why the crazy spring works is inside the housing.

The typical mud and grit that a 4 wheel drive truck gets into is exactly what these shifters don't need.....

I have never seen one "wear-out" or even break (internally). I have seen quite a few with the mounting bracket cracked. I can only assume from abuse, when a clean-up and adjustment would have fixed it.

There is a hole through the middle of the housing and levers that "centers" everything for the adjustment. Push a drill bit through this hole, aligning all of the levers, then adjust the length of the connecting rods to fit.

[76/85 Truck]

Thanks! I'll have to take it apart this weekend and grease everything. So that case comes apart that holds all the inter workings?