I have a 2003 Toyota Avalon with about 58,000 miles on it. I purchased this vehicle slightly over a year ago. Recently it started to give out a grayish color smoke from the rear tail pipe. I took it to a mechanical and they found that the engine was full of sludge and gelled oil. I was told that I needed a new engine (approx. $5,00.00).

I have had about three oil changes since I purchased this vehicle. It had approx. 40,000 miles when I purchased it.

Has anyone else had this problem and how was it resolved? What would cause this to happen?