GM 10 bolt water-proofing

I recently got my truck stuck in some water, and in a matter of 5 minutes, my rear end became water logged. Anyone know how to prevent this from happening again, because i dont want to keep changing milky oil?  

This is not as easy as it seems. The obvious is make sure all the seals are in good shape but the problem lies in venting of the rear axle usually. Like it or not it must be vented becauseas it heats up the air in it expands and when it cools it contracts. You could plug the vent  but then you can have issues with seals weeping or short seal life. What likely happened in your is that your rear axle was hot (and 10 bolts with big tires can get really hot) and the pressure was equalized through vent tube on it (which is normal) and when you hit the deep water it cooled rear axle quickly creating a necative pressure in axle and the vent was below water and it stucked the water right in. They make vent cap that have little check balls in the to keep water out but you really need to get the vents to higher ground in a protected area so the axle can breath and not sip water too if you plan to run in water a lot. If you want to go the expence you could even setup a regulator system that keep axle pressurized to about 1 to 2 PSI when in waterand will quickly add air to it as axle cools and air contracts on water contact. Soeey if I got a bit technical but I wanted to explain why the water gets in and how to prevent it.