At RPMs under 1200 RPM, I will hear an awful rattling noise that sounds strangely like detonation but it's so intense/high frequency that it sounds like it could come from the gearbox/clutch. Detonation is usually a rather random frequency and a much lower pitch and tends to occur at higher loads in the wrong gear. This rattling can be heard with light throttle application, just as long as the RPMs are low (sub-1200 RPM).

 

Normal, all manuals are like in the Mustang. They even do it in other Fords.

 

Out of curiosity, where is it coming from?

 

It comes from detroit

The Mustang GT/3650 makes all kinds of whines and noises.

 

If your cars an 05 it may be missing two trans bellhousing inspection cover bolts. I believe that applies for the manual transmissions only.

 

totally normal. mustang is made by ford. it rattles and clunks. i like it.

 

Its not normal.
I have the exact problem as you, and after 3 months of arguing with the dealership, Ford is finally giving me a new transmission.

Mine happens in 4th gear, 1500rpm, light throttle load.
Sounds EXACTLY like bottom end rod knock.

Take it back to the dealer, compare it to a new unit.
Trust me, if this is anything like mine, you need a new transmission.

Dealer tore my tranny apart, saw nothign wrong, put it back together, and it sounds even worse, appearing in 2nd, 3rd and 4th.
They still have no clue what is wrong, other than a gear may have been cut slightly off leading to to knocking noise.

Mine is a 2005 GT, 5 speed, buiild date 10/2004

 

I have a 07 GT with the TR-3650. Come to think of it, I can make the rattling sound appear in any gear so long as the RPMs start off below 1000 RPM.

The 2-piece driveshaft and the rear end clunks big time during some of the upshifts.

 

You're not smooth enough....
I used to hate doing low RPM shifts cause of the clunking (ie coasting out at night, not wanting to wake the neighours...)
... but if your smooth and easy...no clunking should happen.

Is the sound you're describing like a chatter?
Like the sound you get when you are at idle and slowly let the clutch out without any gas?

 

Boomer: The chatter that you described can be felt (severe vibration), whereas the rattling I'm hearing can only be heard.

 

Mine does it too, ususally just below 1500 in first or second gear. Sounds like a bunch of marbles rattling around inside the gearbox. I doubt it is a problem.

 

I had this same issue with my 01 GT. It started occuring after the second time I had to have the throw-out bearing replaced. The service manager called it gear rollover. No amount of arguing could convince him it was a problem.

 

What the heck??? I've got 15k on my 07 manual tranny and I've never noticed any noises like are being described here. The only rattles I have sound like they're coming from the door speakers.

 

Thats probably the little plastic covers inside the armrest door pull handle. Easy fix, pop em, put foam in, snap em back

Its in the rattles database in the warranty issues forum.

 

As I noted in my earlier post, mine didn't start doing it until the second time I had to have the throw-out bearing replaced. That was around 65-70K miles.

 

Sounds like my 06 Vert...took it in to the dealer..they already knew about it and Ford had a fix laid on...no charge.

I could have sworn it was coming from behind my radio, and it did sound like detonation at times. But all else is the same, RPM, type of noise etc-etc.

Regards,
Chuck