Without a free wheeling hub assembly an end cap replaces all the parts shown in your diagram. The cap bolts to the end of the wheel hub and has a splined recess that slips over the axle shaft splines.
George, when you say the rear driveshaft is a double u joint setup, you mean there’s a u joint on each end of the driveshaft, correct? I believe the front driveshaft will have 2 u joints as well. That is how most are, anyway. If that’s what you meant, 2 u joints are needed because the driveshaft is not aligned with the rear axle, nor is it aligned with the transfer case. The driveshaft meets both the rear axle and the transfer case at an angle. So a u joint is needed for each of those rotating (and variable) angles. The reason you only need one u joint on each side of the front axle stub shafts is because only one part (the hub and wheel) will ever be at an angle to the front differential (in a solid front axle). Where the axles meet the differential is always directly aligned and needs no u joint. The only angles encountered on your solid front drive axle are the steering angles.
I think I understood your question. Does that make sense?
As I recall, the outer teeth on the inner clutch ring are meshed into the splines in the hub. The axle shaft sleeve is splined onto the axle. When you turn the actuator knob you force the sleeve’s cogs (teeth on the side) to engage into those on the clutch ring. (Twisting the knob rides up on the actuating cam.) When you turn it the other direction, the pressure spring forces the 2 gears apart. So, it’s more like meshing gears in a transmission than a real clutch. Locked, power is transferred from axle to hub.
As you probably remember, in the old days we didn’t have these. You could put the transfer case in neutral, but all the front end parts (wheels, hubs, axles, differential and drive shaft) spun all the time. These were highly praised when they first came out… then cursed when you had to engage, kneeling in 6" of muck.
That’s how I recall. Sound right?
Now, for really complicated, look at Jeep’s system in their part-time 4wd.
Yes, I believe you are correct how the manual locking free-hub works on all counts.
There’s two u-joints at the transfer case, and one at the rear axle. On the rear I understand — and concur w/you — why at least one u-joint is needed at both ends. The curious thing is why on the rear driveshaft two u-joints are needed at the transfer case to handle what seems a smaller angle than the steering angle encountered at both front driveshaft/axles.
Each front half-axle only has one u-joint, located near the wheel/steering knuckle. As you say there’s no need for a u-joint at the other end, where the half-axle meets up with the differential. I concur u-joint is needed to accommodate the steering angle, but the curiosity is why the use of a single u-joint there, instead of a pair of u-joints. I think MM’s explanation above is the reason. On a practical basis, two would be over-kill for the application. Plus space is limited in that area. Still I expect front u-joints were a not unheard of failure item for heavily used Ford 4wd trucks of that era. I’ve never had any problems with them on my truck though. I don’t know if the single u-joint design is used now, or if they have switched to some other method, like some heavy duty version of CV joint.
Most trucks these days dont have solid front axles, so it normally is a couple of cv joints.
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Now I’m curious why a pair of u joints is needed at the transfer case on your truck. I’ve owned several Jeeps, several Chevy’s, one Ford, one GMC and one Dodge 4wd ranging from 1979 to 2013 - none of them were set up that way. The driveshaft must be at a pretty extreme angle? You’d think a CJ 5 would have a more extreme angle though… So you’ve got me curious.
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