So I changed my stock gears (3.31) out for 3.73. The gears ran fine for three months then driving down the road I hear a gear whine and I pull over to see a line of fluid coming from the car. the front seal for the diff is now leaking. Any idea why? Anybody have this problem?

 

Mine pukes fluid out the breather, but no seals have ever leaked. I've had 4.10's installed for 5 years and over 30,000 miles I think.