The clunk noise you heard when you put it in gear from park could have also been a worn pinion bearing too. When I was a younger I had a Bronco that had a 8.8" rear that did the same thing. I drove it that way about a year before it ate itself up. Your lucky when mine let go it also broke the carrier in half and one of the axles with the tire fell out!

The way it sounds your C4 had some issues too. So it's a good thing you had it rebuilt. Now get the jag rear fixed and you'll be all set to go!

 

According to this site, the Jag diff is a Spicer version of the Dana44 and some parts including the R&P are interchangable with minor mods: Jaguar Differential Build

PS: not saying it couldn't happen, but I've never experienced a pinion being completely stripped of it's teeth so it would spin freely. Typically they break a few teeth or parts of teeth and make a horrible racket when run. I suspect you have broken something else like a stub axle or sheared the pinion shaft or yoke.
Complete Jag rear axle assemblies are scarce in some areas, but aren't usually expensive when found, It might be worth hunting down another complete unit and swap the diff assemblies. You'll have spare parts that way as well.

 

Just drain the oil and pull the rear cover , you will soon find out what's wrong .

 

Any chance it's the splines in the yoke? Like AX said, anything inside the diff makes a HUGE amount of noise. I'd bet on the pinion shaft being split or the splines gone.

 

The fact that your jag rear moves forward and backwards under load tells me it is definitely NOT mounted correctly .
Does it have anything running from around the pinion area up to the chassis to support it , jag rear installs are something that is rarely done correctly .
Please put some pics up .
This really needs to be fixed .

 

There are two bars that connect the front bottom of the diff to a cross member that keeps the rear from climbing the gear.

The original link bars keep the axle located. It's just the top crossmember that wasn't located correctly.

 

I popped the cover this morning.

BLOWN spider gears!

The pinion & ring look good - no chips or issues - but the spiders inside the carrier are toast. Half a gear spit out & the other sitting on the pin is laying loose inside.

I think this could be good news - couldn't I replace the carrier or spider gears w/o having to recheck the lash? If I leave the pinion in place & leave the ring on the carrier - I should be able to replace the spiders and put it back in right?

Nothing special needed for that - I probably don't even need to take it out of the truck - am I right? I need to youtube this one.

 

I think you're right, as long as you can get the carrier back in the same exact position. But I would be surprised if the loose parts didn't get into the R&P and do some damage.

 

I just watched a guy on youtube change out his spider gears without even removing the carrier - the ring & pinion stayed in - I'm going to look into doing this - but unfortunately this week is a bust for me.

I'll try to source some parts - If I can't do it for cheap - I'd like to find a limited slip I could put in. But that's dreaming - I think I can do this easy.

 

Bad news - I went out & played with it some more last night.

I was able to get the busted spider gears out - its the two that ride on a pin in the carrier - funny enough the two on the axle shafts dont look bad.

The bad news is the hole the pin rests in, in the carrier, is totally wallowed out. The end of the pin is chewed up to a point - it looks like a sharpened pencil!

So the carrier is junk & will need to be replaced (CRAP)

I want to find a cheap D44 carrier & swap my ring gear onto it - but I'm afraid the axle shafts / splines wont work on the new carrier.

I'm now in process of pulling the pumpkin out of the truck - I'll drop it off at a shop & see if I can find someone to buy this extra kidney I have.

 

Lincoln Locker

Back in my 4x4 & Jeep days I read a lot about people creating what they called a Lincoln Locker - it was essentially a spool - but it was achieved by welding the spider gears so they can't turn.

I'm thinking outside the box here - since my carrier is all wallowed out & it can't be re-used - what harm is there in welding the two remaining gears to the case? That is a NO COST quick solution that will have me back on the road. I could then take my time in sourcing a new rear end - or at least the carrier.

To be honest here guys - I have a nice driver truck - not a show truck & I have blown the wad this year already on my trans screw up.

If I could get on down the road for some responsible driving - I'm not talking about towing an 8000 lb boat or running in the grand national drag races - but just cruising.

I know what my next youtube research topic will be. I mean- the carrier is already junk - it can't cost me any more this way.

Thoughts? Quick & dirty is kind of crappy I know - but it beats leaving in on stands for the next 3 months while I try to scrounge up the cash for a new carrier.

 

Not what you want to do on a street truck. It's ok on an off-road trail rig but not on the street.

If it was me I'd dump the jag rear and swap in an Explorer 8.8".

 

Agreed - but if its fried anyway - what have I got to lose?

The thing with a spool or Lincoln Locker is both axels turn together at the same rate. This is GREAT for traction - like you said off road - but makes for squealy turns as normally when going through a turn - think highway off ramp - the inside wheel is traveling a shorter distance than the outside wheel, thus making fewer revolutions. If both wheels are stuck together they both make the same number of revolutions - something has to give, its normally rubber on the tire, but if components are weak it could be a u joint or CV joint.

OEM's get around this dilemma with the engineering marvel of spider gears that allow each axle to turn at its own pace even when under load.

I could get around this by only welding one of the side gears to the housing - weld the other to the splines - that way only 1 axel gets power & the other free wheels.

Again - I'm talking sloppy seconds here - but since I'm looking for a new pumpkin anyway - what have I got to lose?

Anyone?

 

Worse case scenario, if it would cause you to loose control of the truck on a curve or turn. I would say you have a lot to loose. You could wreck the truck or even worse hurt yourself or someone else on the road. Why chance it?

If you are working on a tight budget I'd say find a junk yard pumpkin or just a carrier assembly.

 

If you want to try a cootie-bob fix, why not put in two new spider gears, and weld a new pin into the carrier (in the wallowed-out hole)? I have to say you could have a lot to lose if your case explodes in a sharp turn with a locker.