Had the TB up on the lift at work the other day changing out the thermostat again and also decided to do a brake flush as well. When I got to the back I noticed that the seal on the front of the rear diff (the part where the driveshaft connects to the rear diff) was leaking and slinging fluid everywhere. Luckily it's not puking fluid more seeping, but I was wondering if anyone's done this repair and do I need just the seal or should I replace anything else while I'm in there? The TB is an 06 4.2L with a GU6 RPO code. Thanks in advance.