Clatter at 3000 rpms or so when shifting

[jarepackard]

My 08 F-350 has 10,300 miles and other than a new radiator and squeeling belt when cold it's been great.

I have an unusual noise when the engine is at around 3k rpms and shifting, almost sounds like a metal flap fluttering of some sorts. It sounds like two pieces of metal lighweight in nature flapping really quickly. Took it to the delaership a few months ago and they said they can hear it, but can't find it. They put some sound deadening material around the firewall or so I'm told, but it's certainly still there. Almost sounds as if it's coming from the rear of the engine near the firewall. Only makes the noise when accelarating rapidly and at higher r's generally while shifting or right before.

[Stymie]

its the truck dropping fuel pressure, to pull power between shifts, or that is the way my diesel tech father explained it.

[dirtyharry]

Have them check the u joint at the steady bearing. My last ford I had to change them a couple of times and the noise would come and go at certain RPM's under certain loads. Get them to put the Chasis Ears on it and check that.
Rob

[Stymie]

i doubt the clatter is a ujoint, if its only at a certain rpm, in every gear.
the ujoint is going to spin faster in every gear than i did in the previous. If you roll your windows down, you'll hear the clatter.

[stewie2]

Does it happen all the time? I was told by a Ford Diesel mechanic today that when they go into the REGEN mode they will make a "clattering" noise.

[Stymie]

Originally Posted by stewie2

Does it happen all the time? I was told by a Ford Diesel mechanic today that when they go into the REGEN mode they will make a "clattering" noise.

mine gets worse during regen, that is how the wife knows its doing one

[Captcaper]

Normal stuff.. Mine get's that as well when accelerating sometimes..And others have reported this as well.
I can't explain what's causing it but someone mentioned fuel rails or oil pressure related..

[stewie2]

I listened for it today and all I can tell you is that is the sound of "making horsepower" I did hear it when on the throttle.

[rlchv70]

Not normal, unless in regen. During regen, the intake throttle may make that type of noise.

Keep pressing your dealer to fix. It may be the HP pump due to a restrictive return line. If it is, then you will eventually fail the pump.

[kona_built]

what do you guys think about the Wastegate opening and closing under peak boost.....you did say under full throttle i think....IMO........