This one is for all you mechanical guys out there. I realize there may be better places to ask but I know some of you are fairly knowledgeable in this area. Today I decided to change the gear oil in my rear differential on my 97 F350 PSD. Gear oil hadn’t been changed since I got the truck and was definitely ready. After draining the oil I was cleaning out the housing and found these in the bottom, along with quite a bit of small flakes. Definitely didn’t thrill me to see. I looked at all the gears and they seemed fine except the one in the back ( forgive me I don’t know all the names) was somewhat chipped on the front of the teeth. I know that a few metal flakes is probably nothing to worry about but these seemed a little much. So have any of you guys seen this before? What should I expect and what should I do about it other than fill it back up and keep driving? Any opinions or experience in this area would be greatly appreciated.

I wouldn't take it too far from home.

Me neither.

Makes a guy wonder how that .22 cartridge got in there though.




Charlie

Side gear end teeth they look like to me.

When you refer to the gear in the back.....are you referring to the big ring shaped gear towards the back of the vehicle (called the ring gear)? Or are you referring to the little gear in the back of the case but towards the front of the vehicle (called the pinion gear)? Either way not good and don't take it too far from home as others said.

Thanks for the input guys. It’s the pinyon gear.

Where's your sense of adventure. You didn't say anything about it making any noises. So evidently it was running good for you. Dump some new oil in it and go on down the road.

Now for real, I would tear it down and repair it before doing any serious hauling or driving. Those pieces shouldn't be there.

Russ

Have to wonder if isn't a bearing out. Check the play in it. Maybe a previous owner replaced the whole 3rd member and missed chunks when cleaned it out.

To OP , the pinion gear is the gear attached to the yoke for the rearwards most U-joint on the driveshaft and directly meshed to the rear ring gear. ( just clarifying ) , if that is the case I would be looking for proper gear 'lash' aka correct gear to gear engagement. A good , old school transmission/differential mechanic can determine if you are in proper sync with gear engagement. A bad bearing can cause this and setting up the differential properly with spacers/shims to correct problems is a difficult diagnosis for the bulk of mechanics. It is a specialty field with very few with the knowledge to properly 'set-up' a differential.

Personally , I have had more problems with the spider gears in a differential. These are located towards the outside of the gear carrier/housing. They directly mesh with the splines on each axle going to both rear wheels.

How do I know this ?
Too many burnouts and doing too much drifting/powersliding/donuts............

Spider gears, there are 4 of them. The rear diffs on a Jeep (ours is a 2003) the patina would wear on the spider gears causing the fluid to look like metalflake.

I would for sure be replacing gears and bearings and checking lash and end play. That's a time bomb right there.

Yep!

Might be cheaper to get the same geared ratio in a complete rear axle and swap the whole unit out might be cheaper and quicker in the end no parts or Backlash to mess with you just unbolt the shackle plates, shocks and other stuff and bolt a good rear end back on.

The junkyard might be your friend here and it might be the simplest way to do it cheap if your not mechanical minded.

Heavy gear oil and go
While it’s running look for one to replace
I believe it’s a front loader easy to change
Just keep ratio the same

Hey ..... first on race day !

Look at car-part.com for the salvage yards. Rather than rebuild, replace instead.

Marten,
Consider replacing the gear lube with Amsoil Severe Gear lube. Pricey but its used in OTR trucks. I assume it is a locking differential? Ford makes the best additive for limited slip diff's (told to me by a Toyota mechanic).
I would personally just changed the lube and additive package and check in another 20K miles.
Wouldn't hurt in the meantime to research some Ford owners forums to see if this is a known problem.

Thanks so much for all the input you guys!

Start shopping around for a rear end. They are easy to rebuild if you have the tools & dial indicator to set the back lash.