Are you sure it's your t-case making the noise? If something was popping in there you should have had metal and junk coming out of the drain. You might want to look at the u-joints real well also...
it sounds like it is coming from transfer case the u joints seemed fine it only does it in 4wd under a load once i take off at the strip it pops for the initial take off the stops..
Mine is doing this I've replaced my cvs still have it but mine does it all the time when stopping or boosting up or in 4 wheel drive tcase is new im thinking mines the front diff
Do any tranny work lately? I had a pop like you descried doing 4wd launches and it turned out being my cross member that wasn't bolted down tight enough. Just my $.02
I think it sounds like pump rub pull the t case take out,take the sensor out pull the rubber plug and spread the snap ring,take the bolts out and pull the end housing off.ill bet your rear housing has a small hole that only leaks when you drive it
im goin to try replacing the chain and see if that does it also my driverside wheek bearing has some play so ill be changing that as wheel hopefully the noise stops then