ive saved a few guys trucks at the ramp, dont forget the e brake. i ran and jumped in a few trucks to nail the brakes and stop them from sliding in the water. one guy was like f it, your in there, drive it out please!!!! lol
if your going in the ocean your dealing with tides, the ramps are deadly slick when wet at low tide.
when ever im on a hill or incline, especially like a boat ramp with the trailer loaded i always put the trans in neutral, set the e brake, let off the foot brake to let it roll and settle, then put it in park. this way your not sitting there with all that weight on the park pwal. and it will come out of park with ease vs pulling on it then hearing that ping sound.
remember to put it in gear first, then take off the e brake. or you just defeated the whole purpose of setting the e brake.
for the most part i maybe used 4wd once or twice with my 2500 hd and 4,000 boat. if i needed it i stopped and put it in 4wd. saw no need to put it in 4wd unless i was getting stuck, and that was a rare event for me.
i also had a locking rear, maybe the difference. if one wheel slips a 1/2 turn you got both back tires locked in fully, like a spool rear.