I have noticed a strange noise that sounds almost like an elevator cable stretching in my 5.4L Scab. It is coming from under the hood.

Basically, if I step on the gas between 20-50 mph and then abruptly let off of the pedal, I get the noise almost every time.

Has anyone else experienced this or have any idea what it could be??

 

Some different things happen when you mash the gas to the floor, and then let up all the sudden. It sounds like when you are lifting the pedal, its right before a shift point. Your whole truck, from the computer, through the engine, to the tranny, is anticipating an upshift. When the tranny shifts, its putting more workload on the engine, evidence is the decrease in RPM's.

I think that if you mash the gas, as in a passing situation, wait until you run through all the gears. A good place to do this would be a highway onramp. Then let off the gas gently, not abruptly. The noise shouldnt happen then. When you let off suddenly at 50 or so, its affecting your vaccum, which plays a part in the tranny shift.

So ultimately, my advice is if it happenes when you let off suddenly, dont do it.