Well, I washed the thing and the engine looked fine, so sawdust or
anything other than a few bugs there. With the vehicle stopped and
running I put my hand in front of the radiator and there was some
pretty good suction going on there, so I'm guessing it's most likely
the thermostat.

I picked one up and will install it this weekend when I have enough
time. Will let everyone know how it goes.

Thanks for the help.