Checking rear diff for contamination

After this incident I decided to do the rear differential breather mod.


I got 4 qts of Lucas 80w-90 at Autozone and figured I will change the oil just in case, but what else can I do to ensure I don't have mud in the diff?

 

You nailed it spot on. Drain and refill.

I did the same thing 2 days after I bought my '12 4x4, dove her into a mud hole halfway up the doors to test her out. Then a week later I learned that the rear diff has the breather on top of the housing and panicked. I drained and refilled mine right away but luckily no water got in there.

I did the rear diff breather mod right after that too so that I don't have to worry about it anymore.

 

I think the breather mod is your best bet, besides staying outta the mud. But thats not as much fun. Keep up your momentum

 

If you do happen to see some water come out then I'd recommend flushing it out before refilling. Get the cheapest gear oil you can find such as Coastal and drive it around with that for about a day, then drain that stuff out and refill with the oil of your choice.