Harmonic Sensor malfunction because of noisy tires?

[WD8CXB]

This is not an F-150 problem, or maybe it could be? This pertains to a 2020 Expedition 3.5L Ecoboost with the FX4 package.

My wife planned on putting BFG All Terrian KO2s on her 2020 Expedition this week. Later this summer, I want to put them on my 2023 F-150 3.5L Ecoboost with the FX4 package. I had them on my 2004 Jeep Grand Cherokee and loved them.

My wife called the dealer to check the price, and they recommended Michelin Defender LTX M/S. However, they said the KO2s were too noisy and would mess up the Expedition’s harmonic sensor. This would cause multiple problems and also void any warranty repairs.

I feel the claim is false. I always thought the harmonic sensor was to detect abnormal vibrations in the engine. I learn new things daily, but I think the tire claim is BS.

Is the dealer right?

Sponsored

 

[Buyer2021]

... harmonic sensor ...

What the heck is the "harmonic sensor" ?

Is it connected to the flux capacitor?

I learn new things everyday but feel the tire claim is BS.

You've got a good feeling on this one.

 

[LariatSpaceWhite2.7]

Following!

 

[Buyer2021]

I have heard of a harmonic sensor on the 5.4L V8

Hmmmm, don't have a "harmonic sensor" on my 2005 F150 5.4l V8.

"Knock sensor" and dozens of others, but none called a "harmonic sensor".

Yes, the "knock sensor" (found on virtually all modern engines) operates on an acoustic / vibration principle, but its sensitivity is tuned to a very specific frequency range related to what's happening in the combustion chambers and there's no chance it will be confounded by tire noise. Supporting evidence is that the Ford troubleshooting procedures for the knock sensor make absolutely no reference to tires, tire noise, or drivetrain vibration as a possible problem relating to the knock sensor's proper operation.

I, too, call BS on this one.

 

[Hog_Johnson]

Maybe it has something to do with the active noise control?

https://www.expeditionforum.com/threads/2018-platinum-active-noise-control-on-off-fuse.43493/

 

[WD8CXB]

Hmmmm, don't have a "harmonic sensor" on my 2005 F150 5.4l V8.

Sorry, my bad, I was thinking of the knock sensor as the "Harmonic Sensor". That was the only thing I could even remotely figure the dealer was talking about.

 

[Zengineer]

The Sensor thing sounds completely made up...but the fact is that the Michelin Defender LTX M/S are great tires.

My guess is they are mansplaining her based on a lot of past complaints about tires that are "like totally noisy".

 

[WD8CXB]

Maybe it has something to do with the active noise control?

https://www.expeditionforum.com/threads/2018-platinum-active-noise-control-on-off-fuse.43493/

My wife has an XLT and would assume it doesn't have active noise control. I also don't see how different tires would create issues other than a higher level of noise. Hard to tell what he was referring to since I did not talk to the service guy. Would assume he did not want to sell the BFG tires for whatever reason and came up with his own excuse. My wife is not buying the reason either. We have had countless vehicles, and we have added aftermarket aggressive tires without any problems. As we get older we do less camping and off-roading but aggressive tires do help in the mud and snow.

 

[sts90]

It is called active noise cancellation and it is done by speakers out putting sound. This started in 2019 on models equipped with B&O sound system. There explanation is possible but would mean the new tech has major limitations or there’s a known problem with no TSB. I would call a couple different dealers in different area’s to here what they say. Expeditions running aggressive AT tires would be very low volume and possibly why this seems out of left field. However, I am very skeptical on explanation given.

Sponsored