Rear pinion seal problem.

[kc24viking]

2003 chevy K2500 pinion seal leaks when pulling a load. Put a new seal in and the problem seemed to get worse.

[MikeyB]

2003 chevy K2500 pinion seal leaks when pulling a load. Put a new seal in and the problem seemed to get worse.

Mine leaked at the tailshaft. Took me a while to diagnose it. I thought it was the "infamous" rub through the transfer case. I had fluid thrown all around the truck's rear and on the bed behind and above the tailshaft. I finally pulled off the plug from the tailshaft and put on some JB Weld, no more leaks!

[JohnC]

Make sure the vent line is open and doesn't have a low spot in it to trap a slug of fluid (and prevent venting.)

[cowboywildbill]

Could be the yoke, Also it's a little tricky putting a seal in, the spring can jump off and that would make it worse. The correct seal driver helps, but isn't always a perfect install even with using it. Check the bearing play and check the yoke very closely. I had two seals put in the transfer case tail shaft on our 07 by the dealer. then they replaced the yoke along with another new seal and problem solved. The old yoke looked good to the naked eye, but something wasn't right. It can be frustrating for sure.