Hello,

I have a 2010 F-250 with the 5.4l, TorqueShift, 4:10LS.

Recently the truck starting producing a sound (drone) and accompanying vibration around 1500 rpm. It always occurs as the rpm's pass through the 1500 range when the engine is under load and disappears once above 1500 rpm. It occurs at all highway speeds and in all gears. It comes as fast as it disappears and always around 1500 rpm. The only constant is it's always right around 1500 rpm with the engine under load. When the engine is not under load there is no sound or vibration. It seems more pronounced when the engine is hot. There is no performance issue at all. Just this sound (drone) and accompanying vibration that showed up a couple weeks ago. The truck is stock.

I've checked for loose exhaust clamps and shields. All good there as best I can tell. No other loose parts that I can see.

We pull a 7,500 lb camper pretty regularly with this truck. Pulls fine. Except for this recent sound (drone) and vibration as the rpm's pass through the 1500 rpm range.

Has any one else experienced anything similar? I'm thinking its an exhaust oriented drone but can't understand why it just started showing up.

Ideas as to what this may be?

Dave,

 

Just a guess Dave,

I had a similar experience, turned out to be the cooling fan. Check for cracks and missing pieces.........

 

I was thinking it could be fan related too but never thought to check for cracks and such in the fan blade.

Thanks. I'll have to look at the fan blade.

Dave