Hello,

I have a 76 F150 4x4 and I am not really sure about the 4x4 system. I know you have to turn the hubs to lock, to lock them in, but I am not sure about the shifting into 4wd. All the other systems I have seen before have a 4HI, 4LO and 2wd, but mine only has 4HI and 4LO. What is the deal? How does it work? Am I always in 4HI because it does not feel like it or does it engage 4HI when the hubs are locked and 2wd when unlocked?

Thanks guys!!

 

If you have an NP 203 transfer case, then you may not have a part time case and you may always be in 4wd. That being the case, you should not have locking hubs, and you should have a LOC feature on the transfer case.

DO you know what kind of transfer case you actually have?

 

I have no clue about the t-case. All I know is that it have locking hubs and on the shifter is 4LO at the top, N in the middle and down, to the right and up is 4HI.

 

I am sorry, it says, lock LO and lock HI

 

This indicates an NP 203 transfer case, and you sort of answered my next question. Where I was leading was whether or not the shift pattern was straight or a "J" shape.
I ask this because if you habe locking hubs, then this might be a case that has been converted to part time.
That being said, many companies made conversion kits, and some included a new shifter with a shift ****. Some did not. Sounds as though a PO did some changing and did not let you know.
I would unlock the hubs and try to figure the pattern of the shifter. Its full pattern and not what the shift **** tells you, because the shift **** is wrong.
My hunch tells me that you have a converted 203 and just dont know how to shift it.
I would put the truck in neutral, block the tires, unlock the front hubs, maybe even raise the rear tires off of the ground and shift the case by moving the lever. AFter each selection, I would turn the driveshafts to see what happens. With the truck in neutral, you should be acle to turn the front and rear. With the truck in park, or in gear you will not be able to turn either of them unless the case is in neutral. If the front shaft will turn by hand, then you have found 2wd. Shift until you can get a good feel for what is going on, then start the truck, take the blocks out, and try it with the vehicle moving.
You will only be able to do any of this once you find out exactly how the shifter moves.
Some Mile Marker shifters used a "J" pattern and you had to push the lever down towards the floor to get it to shift past the saftey detent in the lower part of the "J" pattern.

Can you take any pics of you case?

 

WOW!!! I will get pics tonight and post them for you. I will check out the pattern then too, thanks!

 

Here you go, let me know if you need anything else. I did shift it and it goes as the *** indicates. I did not know that it had to be put into neutral to shift it thought so thanks for that. I did not have to push it down either. I did notice a np on the tcase, not sure if you can see it on the pic or not.

 

I dont have to see the tagl I can clearly see that the case you have is a NP 203. This was born as a full time transfer case and might have been converted.
This case would have had a differential in the output section of the transfer case (thats the giant housing on the back side of the case)
Here is a 205 so you can compare:



So we have established that your truck has locking hubs, so we have to assume that it has been converted to part time. This means that you no longer have the "loc" functions, since the conversion locks the differential in the transfer case.
You will now have a 2wd which differs form the original design.
There is much to now about the maintenance and upkeep of a converted 203. Many folks ruini the 203 because if improper lubrications and lack of maintenance.
Try this link for some reading and it should clear up your shifter issues as well.

http://www.off-road.com/trucks4x4/ar....jsp?id=199953


I also might add that it appears that your shifter is rather low. It should stick up quite a ways further than that. Perhaps you have an improperly mounted shifter or that carpet is messed up, or the body lift is preventing you from shifting the shifter into certain positions.

 

O man, that really sucks a big one!! so the hubs are for nothing? I took a few more pics so you can see it a little better and I found numbers on it too, c11871 F U not sure if they mean anything. Thanks for all the info and the link, I will read up on it.

 

Your front hubs are for something if you have a converted 203. I think that reading the link will shed some light on this subject.

 

yeah crazy, so it is always in 4wd, but the front diff is not engaged until I lock the hubs right? I never have to shift unless I want to go into 4LO and back to 4HI.

So with the side view does the shifter look short still?

Also, while I am in the are, how do I find out what diffs and trans I have so I can get the right lub for them. I figure I probably need to change all of them before I put too many miles on the truck.

THanks for all the help!!

 

A bone stock Np203 is always in 4wd (thus the term "full time"). However, one can be converted to part time and this means that it can be engaged into 2wd and the front driveshaft will not spin as long as the front hubs are dis-engaged.
Factory full time trucks do not have any locking hubs, they have a front axle that is engaged all of the time.
You stated that you have locking front hubs. Assuming a dial that reads "free" and "lock".
Since you have these locking hubs it is safe to assume that either the previous owner listakingly installed them, or installed them as part of a kit to convert to "part time".

If the conversion has been performed, the transfer case shift **** is no longer valid, as you no longer have any of the "LOC" positions any longer.

Now, if your shifter only has two detents, and the two selections are 4hi and 4lo, then I guess there is a posibility that the PO rigged the shifter to only function the low and hi range and has left it in the LOC mode and the case is completely stock.
Maybe you can take a pic of the linkages on the left side of the transfer case.
You should have two rods that attach to the shifter and the transfer case itself.

I know this is all a little confusing, but there are a few variables with the Np203 transfer case that makes this a rather unique case. It could go either way, full time or part time, and it may or may not have the 2wd only option. We can get into that a little later, but lets see if we can help identify whether or not you have a stock case or a converted one.

Does the shifter move at all like that pattern on the shift ****? That funny "J" formation, can you shift it through out that pattern?

The shifter does not look short from the side. It looks just fine.

Regardless of which "diffs" you have, you will be running gear oil in the front and rear axles. If you have a limited slip in either, that axle will require friction modifier. You can get away with straight 90W gear oil in either case.

If you have an automatic trans, then you will need automatic transmission fluid. Look at your dipstick and read what it recommends.

If you have a 4 speed, then you can run the same gear oil that you use in the front and rear axles.

Your Np203 transfer case cant run this type of oil It is too thick to use in the 203 and will ruin the case eventually. The suggestion is 50W oil, but this is often difficult to find, so 40W will work.

Most of this was in the link.

 

It does go through the full "j" pattern. I had tried it before, but did not know that I had to put the trans in "N" to get it to shift. Shifts without hesitation too, nice!!

I will get somes of the linkage tonight.

I read throught the link info and kinda got confused, but it is great info. Thanks again for taking all the time, I am always worked with FWD 4 bangers so this is all new...

 

Ok, so since it goes though the entire pattern, you will have to engage each of the selections and see exactly what it does. Document the position and the selection and you will know what happens. You are trying to verify whether or not there is a 2wd position. A converted transfer case will have 2wd and a non converted one will not.
Verify this by making the transfer case selections and turning the front driveshaft by hand. Converted case will allow you to turn it and a non-converted one will not.
Be careful when you verify this that you do not just have the case in neutral, and that you block the tires.

 

I tried to turn the front shaft and it has a little play, but it stops when turned.

Here are 2 pics of the linkage. Not sure if it is the right linkage, but it is the linkage around the tcase.