06 GT Auto, 110K miles

I am getting a loud rattle/chatter noise in first and second gear when initially accelerating from slow speed or stop. Seems to be coming from either front or center underside of car. Thing is it occurs with foot on gas AND also when I let off the gas. it is a mettalic sound - best I can describe is if a a chain was being dragged across a loose piece of metal. it's a loose metallic vibrating sound.

I had a similar sound occur from the rear under similar conditions (only on tip in, not on foot off gas) not too long ago. Turned out to be a loose exhaust clamp. So I went under the car yesterday and tightened every bolt that I could reach - didn't help.

Any ideas? Bases on the fact that is occur under load and no load, I don't think it is tranny/gear related. I also don't feel any vibration - it is just a noise, but loud. Could bad catalytic converter make this noise?

 

I had that with my of gt there's a metal plate thats on the tranny covering the flywheel that had to be replaced or they forgot to put a couple bolts in , as I recall lol there was a recall for this issue if that's what you have & it's listed in this site too if I'm not mistaken.

 

If i'm not mistaken that is for manual tranny only. Flywheel hitting separator plate. I have auto tranny. Plus I don't think it would occur with foot off throttle.

 

Humm
I just Google so I saw this maybe something here ?
http://www.latemodelrestoration.com/...ang-TSB-Recall

 

tap on your floorpan heatshields...i musta bumped,bent one of mine slightly putting the clutch in and it would flutter at a certain rpm...

automatics also have a dustshield/separator plate- at least older ones did...tap on that too. mine(stick) had a little rattle, I just stuffed a tiny piece of scotchbrite in with a screwdriver tip to put a little pressure on it...

 

Stop get out & if need tie rope on run over body then drive away, this should help the pounding 😨

 

Turns out it was detonation. Didn't sound like it from inside the car, but I heard it from outside when my wife took it for a spin and it was obvious. Turns out I was leaking oil - was low by at least 3 quarts, probably more (I don't know how much cause I just changed the oil instead of adding more since it was due. I'm guessing only 2-3 quarts drained max). It was leaking from the filter area. I didn't realize low oil could cause detonation, but i googled it and sure enough it is a possibility. Today, no noise at all. Hope I didn't do too much engine damage driving on very little oil for about 2 weeks.

 

Loose filter .... or did you not check for old gasket when putting new filter on? I know I've probably had half a dozen or more times (out of "a bunch" over the years) when I changed oil filters and when the old came off, the gasket was stuck on the engine oil filter adapter.


It happens.

 

Ford did the last oil change - that's what I get for not doing it myself. Thing is, the filter was hard to get off when i changed it this time. So not sure it was loose, but it was definitely leaking from that area. I'll have to keep an eye on it.