I've had my XC into the dealer twice to diagnose a problem, with no success yet. When in gear and applying any gas at all, I'm getting a loud engine or drivetrain noise at 1500-1600 rpm. As soon as I rev past this range, it goes away. It sounds like a roar, about twice as loud as the engine normally is at this speed. If I put it in neutral and rev the engine at this speed, it doesn't make the noise.

On the first dealer visit, they thought it sounded like the timing belt tensioner, so they replaced it. They also replaced the propeller shaft(the section of the drive shaft just to the rear of the bevel gear) because it had thrown grease all over the place. Still the noise persists. They had no ideas after second visit. It is slightly better after the car warms up, but not much.

Any ideas?

Thanks,

Steve