I've run out of ideas so I'm hoping you guys can provide some new "lines" of thought.

Firstly, we're talking about a NP203 w/ a part time kit (don't know which one -cheapo or better one) on a '79 Bronco w/ a 400 cid, C6, Dana44 HP front.

With the hubs locked I can't get the front wheels to spin in some loose gravel or the mud, even when the power is put to it.

Case is full of oil and not leaking.

Removed the hubs and everything appears clean w/ new grease although one of the hubs (outer piece) was not installed properly - the spring and cam piece fell out when removed. Put back together correctly and reinstalled.

Jacked up front end, locked the hubs and rotating the front drive shaft does turn the front wheels, but if you hold one of the wheels, the other will continue to turn.

The shifter doesn't seem to go into 4-Lo, which is shifter all the way forward, so I've only really tested it out in 4-Hi, shifter all the way back (toward seat).

Front diff is full of oil.

So, what do you think ???

 

About the only thing that you didn't check is whether the front shaft is turning when you engage the transfer case. Try unlocking the hubs and have some drive slowly and see if the front shaft is turning.

 

OK, the latest. The front drive shaft does turn but that's because the front wheels are turning. When shifting thru the 4x gears it feels like it's going into gear (lo & hi) but there's just no action up front. I don't think the transfer case is turning the front shaft. So, that would mean something's not right in the case. It appears that the previous owner installed the cheap part-time kit. How sturdy is this kit - is it prone to breaking easily, ... ? (:-(

 

The front end will spin the oposite tire if you hold one unless you have a locked differential. If you put it into 4X4 and drive on pavement does the front axle bind and hop?
why dont you mark the rear driveshaft so you get it back on the same way front and rear
Remove the front driveshaft
put transfer case into 4-Hi and see if it drives
then try to put into 4-LO and see if it drives

I have a new set up in my 94 F150 and when I goose it my front doesnt spin but pulls and the rear will spin

 

did you ever look inside your front diff? might be blown spider gears , might not have anything to do with the t case

 

I think it's in the case myself. He said that the wheels turn if he turns the shaft by hand, and that if you stop one wheel the other still turns. I think if the spiders were shot, that wouldn't happen.

I think ponyracer is right - mark and pull the rear shaft, put her in 4x and see if it'll drive with front only. If not, the case is jagged up or not shifting into 4x. I'd lose the 203 and get a 205 gear drive. Much stronger IMO.

Let us know what you find.

Kevin K.

 

I put the Bronco on jack stands and ran through all the gear settings.

The transfer case never turned the front drive shaft, in either 4hi or 4lo, while the rear drive shaft always turned. As mentioned above, turning the front drive shaft by hand does turn the front wheels, fwd & rev.

One thing that I did notice yesterday during my testing, the rear end made a loud, deep CLUNK sound at one point, and then again some time later. Should I be worried about this (Ford 9" rear)?

 

It depends on what you were doing when the clunk occured. If you were changing the t-case gear while the tranny was in gear, it's gonna clunk.

If you weren't shifting gears, I'd pull the rear end out and take a look inside.

K.

 

The clunk occured while "easily" acceleratin thru a tight turn. I happened to be on the left rear wheel. With the rear axle on jack stands, turning this left wheel say fwd, then immediately turning it in rev. there was considerable slack. The wheel rotated through about 6 inches of "slack" before engaging again.

 

Back to my original problem, am I correct in thinking that with the setup I have (NP203 /w part-time kit) I should be seeing the front pulling, in say loose gravel, no matter what, when in either 4-hi or 4-lo position (hubs locked) ? ? ?

I'm just wondering if I truely understand how this system operates, for example is there something peculiar with the operation of the NP203 & a part-time kit together that maybe the fourwheel drive (front) will "kick-in" after there is enough rolling resistance?, or what?

I'm trying to make sure that there is in fact a "problem", before I schedule some shope time for it, since I don't have any experience working on 4x4 systems I would have to drive Her about 50 miles to the nearest Off-Road garage (Bronco's are this guy's thing - he's got 9 and has all the parts in stock), and pay the premium labor cost.
Since the budget is tight righ now, I'll probably have to wait on this move though.

So, to all who have replied and will reply, you are helping me out a bunch, and I really appreciate it.

 

Yes. If you hammer the gas on loose grounmd, the front tires should spin.

As stated above, crawl under the truck and take off the rear drive shaft. It's only 4 nuts in the rear and 4 bolts in the front. Should take you 15 minutes tops. Put it in 4 hi or 4 lo and see you can drive anywhere.

That'll tell you if the t-case is working or not.

Kevin K.

 

This Bronco is mine and I want to find a 205 and put one in, but I don't know how much difference there is in size and bolting it on or price, or how complicated would it be to put one in(limited supply of tools and if it would be to high on the difficulty metter then how long would it take for some one to put it in)?

I'll have to try to see if the front would pull the truck with only the front axle, but I did put it in the air, and put it in drive in 4hi and 4lo, but the front tires didn't move at all, the back tires were going at it though. So, would I still need to take the rear drive shaft off or does this say it's the t-case?

If it is the t-case just to know how much would it cost me to fix the 203, money wise, would I have to put a new part time kit, new WHAT???? I don't know anything about the 203 exept that it was chain driven, heavy, an put on all 78 79 full time 4wd Broncos.

Thanks for any comments.

 

The 205 case should bolt right in. The only question would be driveshaft length. I've never done the swap so I can't say for sure.

You may just want to pull the case and open it up to see if the chain is broken or if there's an obvious problem. Get a Haynes manual for the truck for $12 and it details the disassembly of the t-case.

You should either rent or make a bracket to lift the case with a floor jack. It weighs around 200 lbs. and is very awkward so you need to be VERY careful.

Removal is hard because of the weight, but it's not a highly technical job. You have to disconnect the shafts, speedo cable, vent tube and shifter linkage. There's a bracket with a rubber bushing that holds the side of the case to the frame. I unbolted the bracket from the case (two bolts). The case is held to the tranny with 6 or so bolts.

To make it easier to remove, pull up the carpet in the cab and remove the large cover on the transmission 'hump'. It's about a foot wide and 1.5 feet long. That'll make it a LOT easier to get at the bolts and linkage.

As for testing what you have, putting all 4 wheels on stands is as good as removing the rear shaft. That already determined that something in the case is not working.

Do a google search for "np203" "part time" and see what they are and how they're installed. This'll give you an idea of what to look for if you open it up. Also, do a search in this forum for swapping in a 205. I'm sure you'll find several posts about how to do it.

Good luck.

K.