I noticed the Toyota 4WD truck as soon as I turned into the parking lot on Monday morning. I knew the owner because we'd been servicing his vehicles for a number of years, and I was always impressed by how clean and straight the truck was for its age. It was parked kind of crooked, indicating it was probably towed in, and then I noticed the large oil slick under the engine.

As I started the computer for the day, I decided I'd better check how long ago we'd seen the vehicle. The last time it had been in was about four months and a little over 3,000 miles ago. We had noted that there may be some timing chain noise; at 200,000 miles, even a Toyota might need some internal repairs. We had changed the oil and the customer had indicated he may sell the truck soon.

The owner called a little later and recalled how the truck had come to be in our shop. After doing his own oil change with this new "trick" thin oil that the kid at the local parts store had sold him, the engine seemed to make more noise than before. And, it seemed to be even noisier after it warmed up. To top it off, on the previous Saturday he had picked up half a ton of pellets for his stove, and the truck seemed to get even louder. On the way back for the second half of the load, the engine just let go. He asked if we could just look at the truck and let him know if it was worth fixing.

As the day progressed, we found a hole behind the starter that we...