How to drive the np203

[westsidek20]

Hello to all  my first post, my first 73-87 truck  , mine is a K20 with V8 350, th400 and a NP 203.
What is the proper way of driving the truck? i know the NP 203 is a fulltime 4wd, while driving on the road and highway, does my NP203 has to be in "N" with unlocked hubs? and actually this is my first 4x4, so I'm really new with all of this.
Any info will be appreciated, thanks.

[Blazin]

Unless someone has updated the truck 203s never had hubs.

[Irish_Alley]

The 203 is set up like this
l(lock)
L(unlock)
N
H(unlock)
H(lock)
You wana drive it in h(unlock) if you have it there and your hubs are unlocked also and you still move you have a part time kit installed which is a good thing keep it like that saves gas and puts all the power to the rear. If you ha e it in h(unlocked ) and your hubs are unlocked it hush means you don't have a part time kit installed and you have to lock your hubs the power will go to the wheels with least resistance not goodbif your in the mud then you want it to be locked. Most time if someone put manual hubs on they also went with the part time kit

[The dream]

I have the same thing going on, this is very helpful... you guys know your trucks.

[westsidek20]

Thank you very much Irish,
Alright, I tried it and i can drive in H unlock, and it actually  moves on both H and H(loc) unlocked... i will keep it on H unlocked as you mentioned. So this means i have a part time kit ?? The only time when it doesnt move is on N.
I can really feal the diference in power when its on 4wd in the L's (locked).
Also i have a hard time shifting to the L's and N. What do i do to shift? im probably doing something wrong.
I shift in Park with the hubs locked, should i do it in neutral with hubs unlocked ??
 

[Irish_Alley]

I have a stick and I push in the clutch and then shift. So shift in neutral or park never in gear. Does it move in h lock and unlock with the hubs unlocked. If so then yes you have the kit

[westsidek20]

Lucky me, yes it moves in both H's.
If only i could take of as fast as i do with the 4wd "L" on... i have been reading about maybe changing gears, right now i have a 14 bolt FF rear axel, since i know somebody has already made some mod's to the truck (locking hubs and tcase kit) i dont know whats in the truck. What would be a good gear to have, i would like to be able to take of faster and burn some rubber (it has 33 X 12.50 X 16.5 tires) and how can i ID the existing gears??

[Grim 82]

Remove the cover and count the teeth or read the stamp on the ring gear.  Ring gear teeth/pinion teeth=____:1 ratio

[Irish_Alley]

If you want to spin. Put it in granny and punch it i spun my 38s once on dry pavement don't like doing it cause its hard on everything I have 4.10s so you should have a lower ratio but since you have a 400 if you want to spin them and it wont do it that easy you might not want to unless you do put it in low since something has to take the stress of turning that rubber

[bake74]

    Sorry to butt in, Irish if I am reading this right, if your hubs are unlocked and truck started, if you can move between h(locked) and h(unlocked) then you have a part time kit.  So if you do the the same thing and you can not switch between the 2 h's that means you do not have the part time kit installed on a np203 ? 
     I have been wondering how to check this for awhile,  thanks for any replies.....

[Irish_Alley]

Um what lol. You can't shift from h unlocked and h locked with the truck in park or neutral

[westsidek20]

If you want to spin. Put it in granny and punch it i spun my 38s once on dry pavement don't like doing it cause its hard on everything I have 4.10s so you should have a lower ratio but since you have a 400 if you want to spin them and it wont do it that easy you might not want to unless you do put it in low since something has to take the stress of turning that rubber

Lost me there, didn't get all of it. what does "put it in granny" mean?  and a 4.10 on the 400th is not a good idea?
Sorry for the delayed questions, i had family visiting and took all my time LOL

[Irish_Alley]

On my sm465 I have a low gear only need it when I'm towing sometimes when I'm taking off. Not saying your setup is bad but when you try tp turn alot of rubber something is going to give (transmission or the rear) guess what I'm trying tp say is if you keep turning all that rubber something eventually will give up

[westsidek20]

I get you, im not a racer, and i dont show off (tires are expensive also), its just that my truck seems to be somewhat sluggish and i would like to take of faster, when i step on it, its no way close to burning rubber. I just wanted some pointers because my truck has the 350 on it and everybody just tells me "well it should have enough power to really get you moving"... just want to know what would be a good upgrade 

[Irish_Alley]

Think about this my 350 in my 86 same one in my 79 now but it the 86 she only had to turn 30s but she would struggle to turn them unless the pavement was wet or the tread was almost gone. In the 79 she will spin no problem when I take off. Its all about gearing so with 4.10s she should be able to spin even if you had a v6 in it maybe timing is off maybe trans isn’t in low gear not sure but it doesn’t sound about right