Hey Guys,

I am hearing a faint whooshing/sloshing noise under the driver's side dashboard/footwell area. The noise is most noticeable after the brakes are applied before slowly coming to a complete stop.

The dealer thought it was uneven rotors and ended up resurfacing them but that did not help. I am starting to think it could be condensation buildup under the car somewhere or even air in the brake lines (although brakes don't feel spongy).

Anyone else with a 2020 NX300 FSport experiencing this same noise or have any idea what the cause might be?

Thanks

 

I have a 2019 NX300 Fsport-1 and hear the same thing. Was going to bring it up at my next service, but currently don't know what it could be.

 

The noise you hear could be the power brake booster venting vacuum as you reduce pressure on the pedal. Most drivers, without thinking about it, adopt a habit of gradually reducing brake force as the car rolls to a stop. Otherwise the end of the stop is harsh and abrupt. Try a stop where you intentionally hold the brake pedal down until the stop is complete, then release it; You should hear the sound only at release if it is the brake booster venting. Might help to turn of the audio system first so the noise is easier to hear. There is usually a muffler built into the vent to reduce noise; but the NX is inherently more quiet at low speeds than many other vehicles.

 

I have the habit of reducing pressure of the brakes before coming to a complete stop especially driving at higher speeds; however, this is not the case. The noise as described is a result of driving at lower speeds with the brakes already applied before gradually coming to a complete stop at a red light/stop sign. I have previously diagnosed with the radio off, windows up and down. Again, the noise is only heard in a specific location inside the car which is under the driver's side dashboard/footwell area.

During my visit to the dealership,the technician stated he has heard the similar noise on another NX model, but was not able to fully determine the cause. He predicted it could be normal as the brake pad is making contact/friction with the rotors. This strikes me as odd and I hope it isn't a flaw in the newer NX models.

 

It might be hard in NYC, but if you can find an empty parking lot or lightly-traveled section of roadway, try coasting to a stop without applying the brakes until the very end. An uphill grade will reduce the amount of road required. If you still hear the sound, I think we can conclude it has nothing to do with the brake system.