Howdy guys, first post here.

I've been searching the internet for a long time trying to solve this problem but I'm simply at my whit's end. I've seen a few threads with similar problems but nothing that yielded a solution/wasn't a wheel bearing issue.

Problem: Starting at about 30mph, my 2005 - 5.4L - 2WD - Supercab - Flareside F150 (150K miles) makes a droning/whining noise, coming from the front end.

Initially it seemed exclusively dependent on speed (louder/higher pitch the faster the truck is moving.) Lately though, I've noticed that if I give it just a little bit of gas while moving at highway speed, (just enough to move the RPM needle, not enough to make it shift gears), it will change tones/get slightly louder. Putting the truck in neutral while traveling highway speeds does NOT help with the noise, which leads me to believe it is not associated with the transmission.

My initial guess was that it may have been a wheel bearing problem, but after testing it (rocking left to test the right/rocking right to test the left), it yielded no hint as to which side was the culprit. This started approximately 8 months ago.

Jumping forward to last week - the noise had gotten progressively louder, to the point where I started reactively reaching for the radio to "turn it down," whenever I received a phone call on the highway. I took it into a local auto shop where they insisted I needed to replace the rotor/wheel bearing assembly. I followed their advice and replaced both sides, with a new set of pads (brand new spindle nuts and torqued to 295 as per specs). This did NOT help the problem at all.

Do you guys have any suggestions or ideas as to where to look? Serpentine belt? One of the pulleys? Another bearing somewhere? Fuel pump/filter? Ball joints?


Key Notes:
I tried rotating tires a while back, and I purchased brand new tires, within the last month. Neither helped at all. The sound started after leaving the truck sitting in a barn for 2-3 months (covered/away from elements). I was assured that it was started/run at least once a week to cycle fuel. This may be a hint, or might just be coincidence.

There doesn't seem to be "excessive play" when testing the ball joints (jacking it up, shaking the tire/putting a pry-bar under it)

There is play in the rack and pinion/steering column, but I don't think it is associated.

The noise started out as a feint annoyance that only I, but progressed to where passengers think that it is obvious. I noticed it immediately after picking up my truck after that 2-3 month period (I needed to use my family's 3/4 ton pickup).

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Thank you guys so so much for any and all advice that you have. I sincerely appreciate it. It's gotten to the point where I literally don't know where to look. As a "broke college student" I don't want to spend another couple hundred dollars replacing parts that didn't need replacing..

 

Next test: check tire pressures early in the morning when the truck is stone cold. They should not be higher than the sticker recommendation. I suspect over-inflation.

 

I'll check first thing in the morning. My guess is that discount tire would have inflated to specs, but it's worth a try.

I'm pretty sure the tires say 40psi but the door sticker says 35, where should it sit?

 

One way to help check is to determine whether it is cause by wheels turning or by engine rpm. Does it do it when the truck rpm is steadily increased while not moving? Or, does it only happen when moving? This will help refine your search.

 

It gets louder as speed increases and will slightly change tones when rpm's dance slightly. If I'm coasting down the highway, take my foot off the gas and put it in neutral (rpm's get low), the noise is the same unless the truck slows down

 

Go by what the door sticker says.

 

Psi was sitting right at 32 all the way around. I wish it was a simple fix like that.

 

are you 100% sure its up front? sounds like a driveline bearing to me. my truck in sig has a whine/drone that is speed dependant, most audible at 35-55mph, and amplified when under light load (quiets some when coasting).

 

It absolutely sounds like it's coming up front. That doesn't mean I'm not being fooled into hearing it one place when it's actually coming from the back.

If you can definitively say that your noise sounds like it's coming from your rear end, I don't think this is the same problem.

When driving, my noise gets louder and louder all the way up to 70-80 miles an hour at highway speeds, there isn't a "sour spot" where it's loudest, that's just as fast as I drive my truck.

I also haven't noticed any change when I use my truck to pull a 2 horse trailer ~5000lbs total, a few times a week.

 

Thank you all so much any and all advice! I really appreciate it.

I read something about an idler pulley needing replaced or an alternator bearing?

Does this sound like it could point to either? I also don't believe my serpentine belt has been replaced in 150K miles, and I think it's a relatively cheap/quick replacement... But... "If it ain't broke - don't fix it"

 

if you said you can put it in neutral going down the road, idle down, and still hear it at the same pitch then that tells me it's driveline, not engine.

mine doesn't sound like it's coming from behind me per say.. in fact i can't pinpoint the direction it's coming from. does your truck have a carrier bearing? if i recall, the 2wd supercabs do, and i could be wrong, but that's more what i was referring to in my last post, your carrier bearing needing replaced. did one in my last truck (CCLB F350) and it got rid of the same whine/drone.

 

It really seems as though the sound is coming from the engine department but:

I briefly looked online and the driveshaft itself is non-serviceable for this year model.. it does have a carrier bearing but just like the rotor/wheel bearing assembly... Ford's fantastic engineers made the whole system one piece..

How would I determine if the driveshaft bearing was my culprit?

 

for my F350 it was cheap enough to just go ahead and replace it. did it with basic handtools.

 

Driveshaft is $700-900 bucks. How did you figure out that was your problem?

 

The U-joints and carrier bearing have to be serviceable, but first you need to narrow it down. Find the carrier bearing and have a strong light with you. Look for deterioration of the rubber isolating ring in the outer shell and play of the driveshaft in the shell. If you take the driveshaft apart - first mark with white paint at both ends so you will put it back in the exact same orientation.


BTW, you need to add 3 psi to your tires. Check only when cold. As already said, go by the sticker on the door jamb.