What is the cause and was it preventable??

Many years ago, the shop foreman where I worked said "I'm not spending $500 to fix a fifty cent oil leak!"
I agree with that, although there are always exceptions.
IMO, a diff seal is a fifty cent oil leak.
However, if the leak is bad enough that the gear oil is washing the dirt off of the housing, then it is probably bad enough to replace the seal.
If the yoke sealing surface is grooved, it could be repaired with a Speedi-Sleeve instead of replacing the yoke.
Come to think of it, is the leak at the seal, or from under the yoke retaining nut? Some axles require a seal of silicone under the washer, to seal the splines. If that seal deteriorates, it will leak.
As previously noted, the leak WILL return. ALL seals seep, that's how they keep lubricated. Most don't seep enough to be noticeable. When the seep gets bad enough that dirt starts to build up, it is about to become a leak. When the dirt gets washed off, it IS a leak, and the choice is yours: Fix it or live with it.

The seals are wear items. This applies to the axle seals (near the tires), and the pinion seals (at the driveshafts). They could fail before 100k, or last over 500k. I lost the front pinion seal on mine at ~86k miles. Nothing can prevent it, and no it will not show up as a diagnostic code.

Causes of failure can be bad axle or pinion bearings causing excessive movement of the axle shaft or pinion shaft and resulting in premature wear of the seal. Another is a plugged axle vent tube (or kinked tube) causing a buildup of pressure during use that forces fluid out of the seals. Grooved or rough shafts where the seal meets can tear the seal before you drove one block. Then there are foreign objects from inside or outside.

You can easily check the lube level in the differentials. Remove the fill plug on the axles and stick your finger in there. The lube is supposed to be to the bottom of the hole (just before it runs out). If lube runs out your good (or sitting on an angle), if you can't get any on the end of your finger when you stick it in there then you're low. If you find yourself adding lube frequently (more than you want to deal with or it is causing a mess) then have the seal(s) replaced.

Thanks all for your quick response(s). It has not happened before, what I mean is I do not what it to happen again - somewhere in the future. Also, does anyone know if this would show on error Codes For 2003+ 3rd Gen Dodge Trucks which - I believe - gives a complete list of diagnostic trouble codes?

Finally, no one said what may cause this to happen. BB

boston blacky wrote:
...
I don't want a repeat of this issue, as I don't have any extra hundreds kicking around, like most folks these days. :?

Thanks in advance -

Has this happened before?

Was it dusty fluid? Or clean looking greese?

My aunt had a "Hole in the boot" of her front wheel drive car. Funny how it had no dust on it when she took a close look at it, like it had just "Happened" after she drove in there. Never went back to that rip off place, and had it fixed someplace else.

If you don't have drips in your driveway from the seals, stop going to that place for service. If the next place says the same thing, have them check the fluid level. There is a couple of gallons of rear axle fluid, so unless you really see a lot of it dripping, it will be good for another 4,000 miles. Of course if there is a 4" puddle under your truck, you have something to worry about sooner than later.

By now, any oil sprayed on the truck will look dusty (from your driving home). You can wash that off with a garden hose, and then if the dusty fluid comes back, you might have a problem. If it stays clean, you have a greedy mechanic. Sad to say that though. Most are hard working guys who pay there bills and make ends meet.

Fred.

Pinion seals are a common failure. Even after replacing them they may still leak again eventually. If they are not slinging oil i would leave them alone.

boston blacky wrote:
My 2005 Dodge Ram 2500 Diesel has a little over 100k miles. Overall and "good old truck", but a recent inspection reveals front and rear differential seals need replacing. Leaks were spotted by a local head mechanic when he rotated my tires.

My question is what caused this to happen and was it preventable?

I don't want a repeat of this issue, as I don't have any extra hundreds kicking around, like most folks these days. :?

Thanks in advance -

Which seals are you referring to? Diff cover gasket or the actual seal where the drive shaft is? If it's not leaving a spot on the floor I wouldn't worry about it. That's their job when they rotate tires. They will sell you anything they can.