cannot figure out which Transfer case I have

[76CrewCab4x4]

I would like to know a few things.

1. Which Transfer Case do I have?
2. Which Fluid does it take?
3. How difficult is it to replace the rear seal (where the rear shafte exits the case)?


I have a 76 K20 Crew Cab with a 350 engine and a Th 350 Tranny.  It does have the after makert B&M locking hubs.  It is a cast iron case.  The shifter shows.
L-loc
Low
N
Hi
H-loc

I cannot locate an I.D. tag or plate.  I have found some raised numbers by some raised letters saying GM but the numbers are hard to discern.

I would like to change the fluid in it  but there seems to be some debate from prior postings in which fluid to use and/or what weight. The fuild seems to be low and it looks like from a small leak at the rear seal where the rear shaft exits and then attached to the rear drive shaft.  The leaking fluid appear to be motor oil. Golden in color.

Thanks for your help in advance.

Tom

[BILTUP]

I believe that shift knob corresponds to the NP203.

[BILTUP]

www.chuckschevytruckpages...rains.html

[76CrewCab4x4]

Thanks for the info.  Your photos look like you could have taken them of my truck.  (Except for the Headers).  

When filling with fluid, do I add until it just starts to overflow out the fill hole?

Tom

[BILTUP]

Sorry, not my photo's.  No problem for the help.  Yup just add to the fill plug.

Edited by: BILTUP at: 3/10/07 10:54 pm

[VileZambonie]

10w30 goes in the NP203

Believe it or not Autozone's website also has a lubrication guide and repair information that can be pretty useful...

www.autozone.com/servlet/...1e9157.jsp

[76CrewCab4x4]

Thanks to all for your help.  Looks like I'll be under the truck this weekend.