Hello,
I am a fairly recent user and I love this site.
I have a 76 highboy aquired in June with an NP 203 TC and locking hubs. How can I tell if this TC has had a part-time conversion or not without looking inside?
Also, I think I read in one post that the chain can be replaced without dropping the TC. Is this correct?
Another thing, When I put the TC in low (not sure which low, very hard to shift) it worked fine the first time. The next time, it popped real loud and kicked back out. Could that be due to the chain?





I drive a Ford because I want to go everywhere my Tonka would go.

 

The reason it popped out is more than likely the shift linkage.
Mine poped out of 4wd on me one time, and had to get pulled out the hole about 4 feet. Man I wish it wouldn't of popped out(for more than one reason), but I was just about out.
Any, I got pulled out, unhooked the strap, and started driveing away, and it popped back in 4wd.
Needless to say, my front driveshaft broke, swung and cracked my trasmission, and it went down hill from there.

I hate the shift linkage. It is almost impossible to adjust the 4 linkages perfectally for it to shift like it is suposed to.

IF it has a part time kit, the the shift pattern would be
4wd lo
2wd lo
N
2wd Hi
4wd Hi

So you could put jackstands under all four corners of the truck, and put it in 2wd hi, and put it in drive with the front hubs locked it, and if the front tires don't turn it has the part time kit.

I don't know if the chain can be replace while the tcase is still mounted, but if it hasn't been done, then it prolly needs to be even though it doesn't seem like it has to much slack.

Now there are 2 part time kits, and it might be worth knowing which one would be in there.
One is a couple crown gears that get rid of the spider gears in the t case, and if that is the one installed, then you'd want to take it easy off road, b/c they don't hold up well to hard abuse.
The other is a solid shaft, and this is of coarse the better coversion, very strong and dependable.

Any more questions, I'll do my best to help, along with the other very helpfull people.

 

Thanks MBBFord,

I've already got the front on stands. I'll raise the back and give it the part-time conversion test. Would the truck have had original locking hubs along with a full-time TC?

I'm gonna try adjusting the linkage. I just found that in my manual.
I'll probably have more questions as I go.
BTW, nice Bronco!

 

Thanks for the complement.

The trucks didn't come from the factory with locking hubs.
If you think you can adjust the likage then go ahead and try, but try and mark where it was to start with, with a marker, paint, or somthing. I messed with mine a couple times, and get the low to high shift to work real nice, but the 4wd wouldn't catch, so I ended up disconnecting the linkage that switch 2wd to 4wd and would crawl under and manully put it in 4wd.

Good luck.

 

Wow, sounds like the linkage can be a bear. My donor truck has an NP 205 with all the shafts. IYO, would I be better off just switching TCs than trying to mess with the linkage? I wanted to avoid that switch until after winter.

I drive a Ford because I want to go everywhere my Tonka would go.

 

I'm swapping mine, b/c there is no possible way I can fix my linkage, my driveshaft broke and tore them up.

IF your 203 shifts into 4wd ok and holds, then it should be fine, but I can't take it, mine gave me to much trouble. The only down sides to the 203 is the weight, linkage, and the chain driven part. But even though it is chain driven, it is still pretty strong.

If I were you, as long as it's working, I'd keep it, but if it gives you trouble, the first time you have the time to swap, it'd a great improvement, expecially since you have a donor truck with all the parts.

 

more than likely, exspecially if you are having trouble with it now.

another easy way to tell if it has a parttime kit-

if you unlock the front hubs, and go nowhere in drive=full time.

plus, trucks with full time tcases normally have drive slugs in the front.

 

You should be able to turn the front shaft unless it is in 4 lock, I had a 203 (devorced) with the part time kit and it was prone to kicking out of 4 lock, It wasnt all that bad until it spit out the part time kit thru the tail shaft housing ..... Go with the 205 and get rid of all the worry the only thing you lose is the low ratio unless you use just the gear box and put your 205 behind the 203 they make adpters/doublers for that applacation ....

 

4X4X4RV, What do you mean you loose the low ratio?

They both basically have the same 2:1 low ratio, but you might be thinking of 2 low, which sounds good, but I've never used it for anything other than to dig some holes while power brakeing.

 

I was saying that you would lose the higher ratio 4 wheel low, But I did some quick research and found that both of them ( 203 and 205 ) both have the same ratios ...
( scratching My head ) Im still trying to figure out where I got the idea that they were different ...... I Apologize for any confusion

 

They are different, but not by much.
The NP205 has a 1.96:1 low ratio, and the
NP203 has a 2.01:1 low ratio.