Im approaching 30k miles on my truck already, Im at 26k right now...When should I consider replacing my brake pads, and do I all do all four?

depends on how they wear, i had to do mine at 20 front and back, 40k front, and am at 60k and needing all 4 soon

wow ive already got 40,000 and im still on the stock brakes

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i had to replace mie at 20,000, and again this past sunday at 42,000, but cuz of all the brake dust I always get on the front wheels, i think its cuz of the way I drive [dunno] bosch is good brake pads tho.

Take off the wheels and do an inspection Jon.
Brake wear really depends on what type of driving you do.
Lots of start stop action and the brakes wear faster.
Lots of highway and they can last twice as long.
I doubt the back pads would need replacement yet, but if you trailer that jet ski allot maybe.
Even the few extra hundred pounds of the jet ski and trailer will wear all the brakes faster.
Visual inspection is the only way to go and front brakes usually wear out much faster than rear.
You have to replace the brakes in sets (fronts or backs) but not necessarily all four at once.

I traded my last truck at 50k miles w/ the stock pads/shoes still in! And they weren't any more than half worn. AT vs stick will change things too. My last truck was prolly the lightest Ranger made: XL Sport w/ the 2.5L and was stick. I don't do a lot of stop and go, but then I don't put a lot of miles on either.. Do what Neil said: give the pads up front a look while rotating your tires or something..

Im at about 76,000 miles.. and I just put my 2nd set of front pads in last weekend!!! New rotors too.. they seemed fine till last thrursday.. i started to feel and hear them actually grinding into the rotor.. so that sat morning i replaced my pads and rotors. there was absolutely nothing left on the pads at all when i took them off.. it was scarey to think that i was driving around with them on my truck like that.

I have almost 40,000 miles and my pads are fine. Last I checked, they were about half. I should probably check them again.

But yea, just take a quick look at them and decide. Whenever mine look about 3/4's worn (great grammer right?) I'll change them.

Yeah, if you wait until the wear indicator starts to scratch, then at the very least you should get your rotors turned. Unfortunately, you can only turn a rotor once or twice before it needs replacement. If you're too heavy on the brakes, the heat and abuse can warp them.