welcome to the site.
if you haven't bought the truck yet, here's a couple of things to check before you buy.
1)blowby. when the motor is warmed up, pull the oil filler cap and fire it up. observe the amount of smoke coming out the filler neck. does it go away when you bring the rpm's off idle. if there is a massive amount of smoke and it doesn't clear up, you have a problem. keep in mind, this is not a perfect test, it's better than going in totally blind.
2)get under the truck and check where the head meets the block at the back of the motor. if it's dry, that's great. if there is a presence of moisture in the form of oil, that's normal. if there is a presence of oil and coolant, that's not good.
3)with the warmed up motor running, squeeze the top radiator hose. hard a a rock? not good. squishy? good.
this is what I look for when I buy a truck. often, how picky I am depends on how much the asking price is and what I am looking for in the truck.
good luck!
if you really feel like getting in the pool of piranhas, we're getting together on sunday the 28th of this month, for a BBQ 2.5hrs south of you, within spitting distance from San Jose airport. check out the post in the events and get-togethers section