For the past week when im accelerating, when it reaches around 2000-2200 rpms it sounds like there is grinding noise. The noise is either right under me or in the engine(i can't really tell) The noise happens until i get faster or let off the gas. Sometimes it doesn't happen but it also seems prone to do it when im going at an incline and having to get on the gas a little harder. I'm taking it in regaurdless to get an oil change this coming week but i just wanted to see if you guys had a clue..


Its an 06 4.6L 4x4 by the way.

 

Like to help ya but I/we need more info. What type a grinding ? Is it loud ? ? Maybe you better let the dealer handle this one.

 

take it to dealers should still be undr warranty

 

I don't hold much faith in finding a solution to this. I had the exact same problem and all three dealerships I took it to told me they couldn't hear it.

Make sure a passenger can hear it as well. Mine seems to get really loud around 75 mph (which is ~2000 rpm).

If they do figure it out I would be quite interested to know what it was.

EDIT1:

Does it only happen under load? That is, if you put it in neutral does it go away? If you rev it there in neutral, does it exist at all? IF it is, that's the exact issue I have.

 

I haven't tried putting it in neutral but it seems like when im tryin to accelerate fairly quickly it will happpen...its not VERY loud but you can definitely hear it.

 

check the u joints in the drive shaft.

 

Are you sure it is grinding and not 'pinging'?

The driving conditions you describe are exactly the time one would expect the engine to ping. Pinging is also known as pre-ignition or detonation. It is very hard on the engine. Basically, due to low fuel quality, high combustion chamber temps or pressures, the fuel ignites while the piston is still going up.

Low fuel quality and low octane fuel can be a big factor. Try running a tank of premium and see if it improves.

 

Could it possibly be coming from one of the front wheels? 've seen a few f-150's with an idependent wheel end (IWE) that partially engage and make a grinding type of noise. I'd say since its under warranty, take it to the dealer...

 

Wouldn't that happen when the engine is in neutral as well? Like, as it's revved?

 

Yea i tried the neutral thing when i got home, didn't make the noise

 

No, it would not. You will generally only get pinging when the engine is under load. Under a heavy load, the cylinder temps and pressures are much greater than when you rev the motor in neutral. Cylinder pressures and temps are usually highest when lugging the motor, like when you are tyring to accellerate at low rpm in a high gear.

The V6 has to work pretty hard in a heavy 4x4 F150. It might not be pinging, but the rev range and driving circumstances he describes are exactly when I would expect a motor to ping if it was prone to it. If the gasoline being used is of suspect quality, it would be even more likely. It is easy to find out by getting a full tank of the best quality pump premium you can find in your area. If it goes away or improves, you will know it is pinging. It's worth finding out as pinging plays hell on your engine.

 

I heard what I thought was a grinding noise coming from my 01 and it took forever to find it was the a hanger for the muffler just vibrating at a certain rpm, just tightened it up and it quit.

Just a suggestion.

 

I don't have a v6

 

If his is anything like mine it's not a "pinging" but a constant hum. To the point where sometimes it harmonizes with my music.

Now I will be the first to admit I have no idea what pinging sounds like. Could pinging sound like this?

 

Basic principle is the same. Have you TRIED premium fuel yet?