NP203 to NP203 swap- Where to start?

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redneck_reed78

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My current NP203 refuses to go in to 4-LO so I said to hell with it and I bought a claimed to be working NP203 for $50. I am going to a Memorial day 4x4 event and it's time to swap em' out over Spring break. I have never even done anything close to this, and from what I can understand it shouldn't be too hard, but where do I start and how should I go about this? Also is there anything I should be careful of or look for? Sorry for yet another set of dumb questions out of me but I'd rather ask a few dumb questions than screw up my truck more than it already is haha! Thanks guys!:shrug:
 

firebane

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Have you crawled under the truck and did proper adjustments to the linkage for the shifter? This is 90% of the time why you can't get them to lock in place for.
 

redneck_reed78

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Yeah I've checked all of the linkages and everything she just grinds the hell out of herself going in to 4-HI as well (but i got full time 4x4) and won't go in to 4-LO at all so I'm pretty sure I'm down to swapping it.
 

theblindchicken

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I know its a dumb question, but have you made sure that you're at a complete stop when you're switching gears on the transfer case?

I definitely learned that even at a slight roll or the transmission was in gear, the transfer case would easily slip out of gear, but grind like no other going into it while the input/output shafts were spinning at different rates.
 

redneck_reed78

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Yeah she is a lost cause. On top of that I found out today that I have a valve ticking. I just dropped $600 on a parts rig. I don't know what to do now boys.
 

firebane

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Ticking valve can be a very minor very major issue. Start with minor and work up.
 

redneck_reed78

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Ticking valve can be a very minor very major issue. Start with minor and work up.

Oh I tore er apart and determined that ain't it so gonna try plug wires and look at the distributer now. Should git er fixed
 

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