Red-Ford

I just watched the video, doesn't sound like gears to me. When you give it throttle you would feel a little lag then it would put you in your seat (from coast to getting on the throttle).

Are you able to work on the truck where you are? I'd jack up the rear end and spin the tires to see if it will make the noise then. From there I'd try to wiggle the driveshaft at the axle and the trans. Is there a possibility it could be a slip yoke issue?

2thousand5.4

Guess it could be the slip yoke hoping over the splines the drive shaft would have to be binding for that to happen. I think it's either something in the front axle or something in the torque converter going bad

jroberts99

2thousand5.4, were you able to diagnose and fix the issue? I had my transmission and transfer case rebuilt about a year ago and I'm having the same whirling problem when I let off the throttle. I took it back to the shop that did the rebuild, but it never makes the sound when the tech is driving. I removed and replaced it myself, so there's always a chance I didn't reinstall it correctly.

97 F150 4.6L 4x4