So for the past few weeks, whenever i come to a stop and am sitting, there is this strange vibration/rumbling sound coming from the engine compartment...that sounds like it is near the brake fluid container. I have a feeling it has something to do with the brake fluid or something because when i let off the brake to move....it stops. Also, if i put the truck in neutral with the brake down....it does not make the noise. It seems to only make the noise when the brakes are having to stop movement from occuring.

The noise is quite annoying. Does anyone have any idea what it could be? The brake fluid is not low.

 

It could be the intake snorkel where it attaches to the fenderwell. There is a rubber bushing that isolates the snorkel. Mine popped out and made a vibrating noise similar to what you explained. Popped it back in, no more noise.

 

i took a look, and nothing looked disconnected.
any other ideas?

I might stop by the ford dealership on the way to my work later today to ask.

 

do you have any problems with your front suspension... vibrations might be from that... may be a heat shield that needs retightened ... next time it does it have a second person in the truck and have them leave it in drive and foot on break and you get out pop the hood and see if you can see anything

 

I had the same problem and it was the snorkel. Even the dealer couldn't figure it out. I found the solution here. Thanks.

 

glad you found a solution to the problem...

 

So it rumbles/vibes with your foot on the brake in gear, but not in neutral? Hate to say this but it could be the torque converter, it might be the ABS module, but it sounds more like the converter.