My Dually rear end leak
 

:confused: First of all, I must thank those who pitched in and replied to my last message. It saved me a lot of time and money.
Now I have another Issue and need some directions. I have an 03 F350 Powerstroke 7.3 Diesel " DUALLY". I happen to notice what appeared to be grease or oil located on the inside wheel Rim and leaking down the tire. It was a small but signficant amount and of coure this alarmed me.
I need to know what this means !! Could this be from a seal or bearing going bad ?? And for those who can tell me, About how much would this cost to have a mechanic tear into??
Another STRANGE FACT took place with regard to this leak. After I noticed this leak I wanted to not drive my rig until it could be looked at, But we had an emergency come up and my wife HAD to drive the truck some fifteen miles. After she returned, I looked for anymore leaks coming from this area in question and found ( NOTHING ) NO LEAKS ..... It stopped leaking????? PLease guys, Do you have any pro knowledge?
Regards: B MacKenzie The Super Cab Ford Man .........