What is the cause and was it preventable??

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.