I recently resolved my extended cranking with my burb. Thanks to this forum.The Chevy dealer,nor another shop could determine why the truck was cranking like that. So I ordered 2 injectors from Rockauto for $35 apiece and wouldn't you know, 2 leaky injectors. It took 10 min to replace! DO NOT by a check valve because this year truck dont have a return line!!!!Truck cranks now everytime. Thanks again to the guy who pointed me towards the bulletin about this.