How do you change Transfer case oil? T case not shifting smooth

[Hillbillydrums]

Total newbie with transfer cases, bear with me. Where do you drain and fill the t case anyways? I've never done so.

And I want to do so because I'll go to shift the t case, in neutral like I should be in, then push around the t case shifter, and it's always so stiff and what have you. Every now and then it'll get stuck in neutral and I cant get it into lo or hi. So I have to sit there untill I wiggle it out.

Low oil? Bad oil? Bad transfer case?

[FlatBlack77]

sounds like the shifter needs at least lubed up. but probably should be taken apart, cleaned/lubed, and put back together.

start by taking off the shifter boot on the floor pan and see what it looks like

[Chadwick717]

Mine did this as well.  Probably just your shifter mechanism. I took off the boot and sprayed a bunch of PB blaster down there, let it sit, and everything loosened up nicely.

If you want to change your oil, it's not hard, but there are some minor differences depending on what transfer case you have. Do you know which one you have?

[Irish_Alley]

mud and dirt can make it harder to shift. but sometimes the gears just dont line up right and you have to rock the truck or put it in gear for a split second. i seen one case where the boy had miss matched rears and he couldnt shift no matter what till you jacked the front axle off the ground and the tires spun freely

[Hillbillydrums]

If you want to change your oil, it's not hard, but there are some minor differences depending on what transfer case you have. Do you know which one you have?

I forgot exactly, but it says low lock, low,  neutral, high,high lock.

[Chadwick717]

Sounds like a np203. Just remove the lowest bolt and drain it, then fill using the fill hole.

[rich weyand]

Note that NP203 takes 30W engine oil, not gear lube.

The NP203 shifter mechs are a little complicated, and get sticky when they get full of mud and dirt.  The solution is to take the boot off and soak the shifter mech down with WD40 or PBBlaster or Silikroil from the top, running all the crap out of it onto the pavement.  Should shift smooth as glass.

Note that you can shift from HI to HILOC and back, or from LO to LOLOC and back, any time, even when moving and in gear, as long as the hubs are locked.

Shifting through the neutral position on the transfer case, from HI to LO or LO to HI, you do not want the transmission in Neutral, you want it in Park, so the input shaft to the transfer case is at dead stop.  Either that or shift it with the engine off.