[jyl]

If you have a good cooler, freeze your food solid, pack it tight, with lots of regular ice, keep it out of hot sun, it will be okay for two days. You're gonna defrost the crab when you get there, so if the defrosting starts a bit at day 1.5, no problem.

Or, get a thermoelectric cooler and run it off the truck's power. If the bed is 65F the thermo cooler will hold 30-40F lower than that, assuming the contents start out frozen. I have such a cooler, $40 on craigslist, it's been pretty useful. The main problem is you can't set the desired temp. It tries to cool to 30-40F below ambient no matter what, so in cool weather, stuff can eventually get frozen that you merely wanted to be chilled.