On my way to elk camp I developed a whine from the engine. I presumed it was the vacuum pump failing and removed the belt to install my non-vacuum pump belt. While the belt was off I started the motor to verify the noise was belt driven, it wasn't, pointing to a gear noise. Due to my remote location I drove the truck 15 miles to camp, 45 miles closer than town. I shut the truck down and waited. Two days later I started the truck and the noise was present instantly and got much louder wh