Hey guys, I've been having a random issue while pulling with my LLY/6spd dually. It's happened about 5 times now where it will develop a loud squealilng/whining noise from the engine area, and it'll lose a ton of power. I've babied it through, and when the noise stops the power returns. I do have a 4" exhaust, and a PPE tuner, but it did it several times before either of these was added. The truck has about 50k on it now. I've searched here, and google to no avail. Any ideas?