Quick Differential Help Please!
 

120 miles from home and stuck!


Pulling out to go to work from my in-laws house and I heard a little snap while driving strait at about 20 mph. Lost the speedometer and ABS and Brake lights aluminated. Well quick look under and nothing dripping so I thought I ran over a cat that was under the hood on the engine or something then flipped up and got the Wheel Sensor harness or something. Well got to work and after work I could see no damage. :icon_shrug:

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Stopped by NAPA auto parts and grabbed a new one at $33 bucks and was going to do a DIY on the replacement. Well I found this instead:


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SO ten I decided to open the differential to get the pieces out and the copper wire from inside the sensor wrapped around the axels on each side. The rest was ground up into glidder. Well I pulled out the wiring and heres a pic of one side.

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Well after the main clean out I found some metal peices in the bottom of the diff:

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I'm thinking the small plunger looking thing came out of the sensor. But WTF are the 2 flat (looks like 1/64" thick) pieces??????? They are about the length of a quarter.

Everything looks ok although there is a little chewed tooth on abs gear thats mounted on the ring gear. This is for the ABS sensor/Speed Sensor/ Wheel sensor. Here is the best pic I could get of the chewed tooth.

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I'm thinking that whatever these flat (almost having a slight roundness to one side) pieces are, I beleive that "it" came loose and broke thaking out the ABS/Wheel/Speed sensor.

Anyway, here are some pic's of the gears:

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I see you have the Trac-Lok. I'm afraid to say this, but I think its chunks of the clutch packs. I bought a 9.25" rear axle for my '95 2wd project and I got it for very cheap because the clutches blew up and ate the bearings. It turned out it locked the axle, broke the ring and pinion, but I rebuilt the entire rear end and put in new 4:10s for about $375 total cost (including what I paid for the axle). Anyway, my point is, those chunks look like what came out of my axle housing. Take the differential carrier out and take a closer look at it.

If that is what they are, you can buy replacement clutch packs for about $60. I'll walk you through the install if you need me to... it was a huge PITA to figure out how to change them, but now that I know the tricks it's easy.

idk if you have an LSD in there hydra, but if you are supposed to than i agree w/ 98_318 looks like pieces of clutch pack,

if you dont i have no clue but i would try to flush out all the metal shavings with clean fluid until they are all gone, then run it for a week or so to make sure and change the fluid again

althought the abs sensor on the rear is a sensor which generates a magnetic signal to the pcm (well it works with magnets to create an electric pulse for the PCM to read) the pcm counts this pulse to measure speed and to decide whether the rear wheels are locking up or not and whether to activate the abs, that said the pice of the sensor hanging into the differential would have a coil of wire in it which would be close enought to count the teeth on the gear as they go past, so there is a chance that all of those parts came from the sensor when it busted, but i would still like to know how it got destroyed if you ever figure it out

He does. I recognize that carrier anywhere. I have 2 of them... one in my 4x4 and the one that is going in my 2wd. That, and I can see the clutches in one of those pictures.

Actually, come to think of it... jack up the rear axle and spin one tire. If the other spins the same way the trac-lok is fine, if the other spins the other way, its most likely the clutches blew up.

I've seen nearly the exact same thing happen to a Ford 7.5, where the sensor broke and all the copper wire wrapped itself around everything.

And yes those do look like pieces of the clutch pack.

I'd do your best to clean it out and keep running it, I wouldn't worry about it too much other than more of the clutches breaking.

I wouldn't. Like I said above, if more of the clutch packs break... and thats not enough peices you took a picture of to be even one full clutch disc so there are probably more to come... they can get caught in the bearings like what happened to the one I bought and rip the bearings apart. Either $60 clutch packs now, or $120 bearing kit and $60 clutch packs later!

After studying those pictures, I agree that those clutch peices got caught between the ABS tone ring and the sensor and ripped them up. You should replace that tone ring though... that one tooth might mess up the signal and you don't want to have to take it all apart twice!

I was referring more to the fact of the copper bits everywhere, since copper is soft.

Replacing the clutches is a good idea though. I wouldn't doubt it was a piece of the clutch that took out that sensor, the Ford 7.5 I saw didn't have anything like that to take out the sensor, weird.

First off thanks for coming over and helping me you guys. I figured someone over there knew!


I turned the rear wheels and they both spin the same direction. I can manually stop one side and the other will turn for about 1/8th to 1/4 turn before stoping. Now after it happened I drove it about 30 miles because I was heading to work and with nobody there I HAD to get there. She drove like a dream? The way back the CEL finally tripped with the P0500 Wheel Speed Sensor which I figured had just got knocked out. Everything in there looks good that I can see but I'm not a Diff man. I always wanted to rebuild it.

1 question is coming to mind tho. I am the 3rd owner to this truck and being so the rear end could have been replaced. One note I see is on the part number on the pinion: 937 392 2 12 98

Now I get the 392 because it's a 392 LS rear end. Now does the 2 12 98 mean the date of manufacture and the 937 the plant?


Last question: In what picture do you see the clutch packs and can you point it out so I can use a mirror to check em? If I can get it ome things will be better because I have my work car and my wife has her car. I can rebuid it or take it in then reinstall.

I doubt you'll be able to see it with a mirror, so you should take the carrier out. Besides, that ABS tone ring needs replacing anyway. But for the clutches, look behind the side gear...

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Here is a picture of the one I rebuilt with arrows pointing at the clutches...

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It still could be a piece of clutch. I had said that cause the one I got worked like an open diff before I rebuilt it, but mine doesn't let 1 tire turn that far without the other turning too. Also, after seeing how the clutch packs work, if there is even half a broken clutch still in the pack, it could still work like normal. If the clutches are fine, I don't have a 2nd guess what it could be!!

IIRC, the Trac-Lok has 8 clutches per side. 4 are splined to the side gear, 4 are notched to the carrier and there is a belleville spring all clipped together in a pack. You can see the clips in my picture (half-circle tab).