Okay, so this is probably my 5th post about this problem, and every time i think i have it figured out, it's still not the problem. here's what it's doing:
it's loudest at the beginning and end of the video... 4 wheel drive clatter - YouTube that clank you hear... sounds like metal on metal hitting as the wheel turns. sounds like it's coming either from the differential or somewhere to the left of it, right underneath the pedals. the 4x4 still works, it's just making that sound, which tells me somethings not right, and i'd rather figure it out now than find it when it breaks.

here's what i thought it was and what i did:
first, i thought it was a driveshaft u-joint. replaced them all.

then i thought it was the passenger side wheel u-joint. replaced that one.

then i thought maybe an internal problem in the diff like missing gear teeth. pulled the diff cover, spun all the gears, nothing missing and no metal flakes in the fluid.

then i thought drivers side u-joint. replaced it.

checked all the splines on the shafts, all the gears in the hubs, and everything looks fine.

now it's still freakin doing it!!! the only thing i can think of is maybe it's a problem with the manual hubs??? when i replaced the wheel u-joints i locked/unlocked the hubs while they were off the truck and everything seemed fine. this really has got me stumped, cause i'm pretty sure that covers everything it could be! anyone got any ideas? at this point i've pretty much settled on taking it to a shop and just saying, "tell me what's broke"...

 

I know it is a pain but have you put all 4 wheels on jack stands and had someone put it it gear and you listen while it is up on stands?That is a tough one beings you have changed all that you have.I just wonder if that drivers front hub is really engaged?Wonder if you could stop that side by hand or would it keep pulling if it was all on stands?

Thank you for your service!!!

 

Daniel, I know we talked about this before, but does your truck have the double cardon joint in the front drive shaft? I am wondering if it isn't staying centered or something and is flopping around when there is pressure on it.

 

that's one thing i might just have to try... just gotta get a couple more stands and a friend, then work up the cajones to crawl under the truck... lol
And thank you for your appreciation!

I'm still not 100% sure i know what the double cardon joint is, but here's some pics of what i have.
here's the front where it connects to the axle


here's the back where it connects to the t-case


and this may be the joint you're talking about?

 

I would in no means lay under the truck .I was talking about getting someone in the drivers seat and you kneel down on the outside of the tire to see if you can pinpoint the noise and see if that one is pulling or not.

 

haha yeah, that's just my "hey yall watch this" humor! lol

 

I gotcha...Send the neighbors kid under there.

 

ya know, there are a couple spoiled little brats running around here... haha

 

Looks like you have the double cardon joint to

 

the double cardon joint is the last one pictured

 

so that joint would cause that clanking sound??? it doesn't sound like it's coming from that far back to me...

 

3X the double cardon joint is that last picture. It has two u-joints joined together and takes a special "self centering yoke" that keeps everything straight. Basically it is designed to divide the angle across 2 u joints instead of kinking one joint at a severe angle. Here is a link to my rebuild thread.

https://www.ford-trucks.com/forums/1...t-bearing.html

If the bearings in the self centering yoke are bad or the spring in the joint is broken, it may be binding or clicking. An easy test would be to pull the front drive shaft out of the truck, lock the hubs in and drive it a little to see if you still have the noise. I am willing to bet you won't and the joint is the culprit. It's an easy test too since it only takes one wrench and a few minutes to drop the front drive shaft.

Be sure you let us know what you find.

 

You can put the t-case in 4hi also to make sure it's not something internal to the t-case.

 

Does it do it if you engage the transfer case with the hubs unlocked? What about with the hubs locked and the transfer case in 2wd. Maybe swap the hubs to the opposite sides and see if the noise follows the hub or stays on the drivers side. Maybe even the bearings. Not only the hub bearings but there is also a set inside the spindle that the stub shaft rides on that are often neglected.

 

FWIW, when my cardon joint went bad, I couldn't hear any noise with the T case in 4HI and the hubs unlocked b/c there was no pressure on the joint. With the hubs locked in and the T case in 2HI I could just faintly hear the noise, but it was very faint.