Long drives sitting / driving after running are really bad for stiffening up. Make sure you are stretching really well after running before getting in the truck. And stretch as frequently as possible during the trip (harder to do if you are driving) I find even a ten or fifteen minute drive home is enough that I get really stiff and it takes a while to loosen back up. You might try icing it too. Good luck. I sure hate to see you having problems with it!