2013 Mustang GT/V8. I notice a tapping sound at idle coming from the front/middle what sounds like underneath the car at idle. The sound is more pronounced when I’m parked next to other cars as that amplifies the noise.
Also when accelerating from a dead stop the car makes a a similar tapping but more like a scraping noise until it shifts into 2nd gear. After shifting to 2nd gear the noise is gone. It does not make any noise if I’m cruising even at high speeds and it does not make any noise if I accelerate and the car is already moving…only makes scraping sound from 1st-2nd gear from a dead stop and never any other time.
I took it to a specialty exhaust shop thinking it was an exhaust leak or something hitting maybe, they checked everything and told me nothing was wrong with the exhaust. No leaks, nothing.
They specialize in exhaust and are not mechanics but they suggested the flywheel might be going bad or have a lot of rust on it and that it needs to be cleaned or possibly replaced but they said they’re not 100% sure. Car runs fine, no check engine light, no misfire, no stalling or trouble starting, no weird smells. Just the noise.
Can a bad/dirty flywheel make this type of noise at idle and the scraping noise when accelerating from a dead stop like I described? What would be yalls best guess?
Link to noise at idle -
Unfortunately I don’t have a video of the noise when accelerating from 1st - 2nd gear but may take one later if needed.
102k miles, transmission shifts perfect, fluid is bright red, changed it and filter 4 times in the past year. Wasn’t planning on touching it again until at least 20k more miles from now
If it’s the flexplate is it safe for the engine and transmission to keep driving it like this until it breaks?
What’s the urgency to get this fixed? Would the worst that would happen when it does break is that I would just be stranded? Or would it damage the engine or transmission when it fails?
How many labor hours would I be looking at for the flex plate? Does the transmission need to come out? Or is there a way to do it without removing the transmission on our cars?
While reading your description of the sound, my guess was the same as yours, a small exhaust leak. It seems prudent to not give up on that theory quite yet. Has the car been run while on a lift and someone underneath walking & listening along the entire exhaust system? Maybe painting some soapy water on questionable exhaust parts, esp the flex tube?
The counter-argument is the scraping noise, which isn’t usually what an exhaust leak sounds like. For that suggest to have your shop watch the engine and transmission mounts, esp during the 1-2 gear shift, and that the engine and transmission are firmly attached. They can do that at the same time they do the test above.
Have no idea how many hours. Given how tight the trans tunnel is, it likely needs to come out. In any event it needs to be disconnected and shifted away from the back of the engine.
Keep in mind, we don’t hear this in stereo. I can’t know the direction of the noise.
5.7 flat rate hours, and that is on a 100% stock car, on a lift, aftermarket exhaust and headers can/will affect that… sorry, don’t remember if that was you or the other, other Mustang guy…
And if the flexplate has any effect on the balance of the engine, it could damage the main bearings by throwing off the balance, it could also put the torque converter in a slight bind and eat up the front seal and hub bushing… depending on how bad it is…
Worst case, the flexplate could explode at almost 7000 rpms, and come through the bellhousing, through the floor board and remove part of your foot for you…
I recommend taking it carefully to a pro driveline shop and confirm or rule out the cracked flexplate theory and replace it if needed…
This is a good point, given the symptom. Also, is it filled w/the oem fluid now? Or was the fluid replaced at some prior time, and they used an “oem-equivalent”? If so, my first step if I had this problem would be to replace the current trans fluid with an oem product purchased at a Ford dealership.
I’ve drained and filled fluid 4 times and changed filter twice within the past year and a half or so. 2 of those times were because I had a defective new leaking pan gasket. So basically the trans should pretty much have completely new fluid. Every time I did the work I used OEM fluid and filter from the dealer. Last change and filter replacement was 4-5 months ago and it’s been running/shifting great, just noticed the sound starting a week ago. Not pushing any serious power and Also I monitor fluid temps and the trans gets to 190 max and that’s if I’m really getting on it. Most of the time it’s between 180-185. So temps are great. Can’t find anything online about flex plate going bad in these 6r80s so it just seems really unlikely that’s my problem especially because of the over maintenance i’ve done on this trans as well
The maintenance done on the transmission doesn’t effect the flywheel/flexplate anymore than it effects the pistons or fuel injectors… When I cracked/broke my flexplate, it sounded like a lifter tap, but much lower, but luckily I can see my flexplate much better than you can…
Not saying it is or is not your flexplate, just letting you know your maintenance has nothing to do with it… But that also doesn’t mean the the torque converter nuts haven’t backed off a tad, have them checked…
