Rattle Identified and Eliminated


w. mitty

GT Owner
Mark IV Lifetime
Sep 1, 2005
704
We all know what a royal pain in the neck rattle repair can be. For the benefit of the GTFORUM faithful, I thought it might be helpful to report on a recent rattle fix that, for once, actually worked. An' I done it all by museff, ya'll. :wink

I noticed a ticking rattle that was present at all rpm, but worst around 2200, under acceleration. The paranoid part of me thought it might be detonation. :thumbsdow. However, it seemed to be related to both engine speed and bumps in the road. How's that for strange? It was driving me nuts, and I experimented with it for a couple of weeks. Sounded like it was coming from behind the driver's seat. FWIW, I DO NOT think this is the famous rattlesnake noise that we discussed here before.

After exhausting all easy possible sources to no avail (the snap on the seat belt guide located on the seat, coins on the floor, the tire gauge I keep in the pouch behind the seat, etc) I decided to put the car on my lift and yank the belly pans, since I noticed the rattle after the most recent oil change that I performed. I remembered meeting the GTGUYS and them telling me that rattles from the belly pans are fairly common.

I went down to Home Despot [sic] and bought a roll of the thin but dense foam for sealing the gap between the camper and the bed on trucks. It has adhesive on one side, and you can find it in the weatherstripping section.

I then pulled the rear pan, and looked for any spots on the frame showing wear or abrasion between the frame and pan. I found several. I cleaned the frame and the pan, then applied strips of the foam tape to the frame between the mounting holes. The process took maybe ten minutes. I replaced the pan, and tightened everything down. The tape is quite thin, and I could not tell, as I snugged the screws down, that it was even there.

I took the car out and sure enough, the rattle was gone. After a week or so of driving, it has not returned, and I find myself driving it just so I can revel in my success. You see, this type of triumph over things mechanical is rare for me. I don't know whether it was the foam, the repositioning of the pan, or the tightening of the one loose bolt that I found :bored, but it worked.

Hope this helps someone, somewhere, somehow, especially those in the future willing to do a search for the term "rattle". :thumbsup
 

Neilda

GT Owner
Oct 19, 2005
3,559
London, UK
How profoundly satisfying! :cheers
 

Kayvan

GT Owner
Jul 13, 2006
4,782
Yup,

I was told pans are a source too.


Never saw that mentioned here before.
 

Empty Pockets

ex-GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Oct 18, 2006
1,361
Washington State
:banana:thumbsup KUDOS, "DUBYA"!:thumbsup:banana
 

DakotaGT

GT Owner
Mark II Lifetime
Dec 9, 2012
1,694
Sioux Falls, South Dakota
Old, old post, that was useful to me today. For the past few hundred miles or so, I was plagued by a very annoying buzz/rattle that seemed to be emanating from behind the driver's seat, or along the bulkhead somewhere. I was about ready to pull the center console off and see if a shifter cable was the culprit, and then (thankfully) saw this thread and took a quick peek under the car. Yup, one of the belly pan screws (under the driver's seat area) was sticking out about 1/2 an inch, allowing that pan to vibrate under certain conditions. Gotta love a 30 second fix. Thanks, W. Mitty! :cheers
 

SYCO GT

GT Owner
Mark II Lifetime
Sep 9, 2006
4,974
California
Ah good tips! Thanks for the heads up about the pans. I'll revisit those to make sure they are all snug, last time I touched them was when I changed the oil. But the dealership has changed the oil since.