What the source says
The documented condition
Lexus documented a droning noise from the exhaust system on some 2016 to 2022 RX 350 vehicles during takeoff or light acceleration. The published procedure checks whether the vehicle already has the revised center pipe with an added bracket and damper, then replaces the older pipe when the exact condition is confirmed. An exhaust leak or loose heat shield needs separate diagnosis; engine faults can also sound similar.
Compare the pattern
Symptoms and vehicle scope
Words owners may use
- deep humming when accelerating
- exhaust resonance in cabin
- RX 350 drones from a stop
- booming noise under light throttle
- low frequency vibration from exhaust
- muffler hum at takeoff
Symptoms in the record
- A low-frequency drone or boom is heard during takeoff
- The sound appears under light rather than heavy acceleration
- The noise seems to come from the exhaust or beneath the cabin
- The bulletin condition is reduced by the revised center pipe and damper
Vehicles and limits
- 2016 to 2022 Lexus RX 350
- The old versus revised center exhaust pipe is identified during inspection
- The bulletin does not list the RX 350L or RX 450h for this procedure
Manufacturer position
What the official procedure directs
Lexus instructs technicians to confirm the drone and identify whether the revised pipe is already installed. The older center exhaust pipe is then replaced with the countermeasure part.
Mileage context
The service bulletin uses model year and confirmation of the specific noise, not a mileage threshold. It stated Federal Long-Term Emission Warranty terms of 96 months or 80,000 miles, subject to eligibility.
Original evidence
Open the documents behind this record.
Manufacturer bulletin · L-SB-0003-23 · Feb 2, 2023
Exhaust Drone at Takeoff or Under Light Acceleration
The Lexus bulletin covers 2016 to 2022 RX 350 vehicles and shows how the revised center pipe is identified and fitted.
Repair paths and safe checks
Match the action to the evidence.
Inspect for the revised center exhaust pipe
A Lexus or exhaust technician confirms the exact drone and checks for the bracket and damper that identify the revised pipe. If the old assembly is present and the bulletin applies, it is replaced with the countermeasure part.
Exhaust components become extremely hot, and the bulletin requires new gaskets plus measurement of the compression springs.
Compare the noise at light throttle
During ordinary driving, have a passenger note whether the sound starts only from a stop or also at a steady speed, and whether it changes with engine speed. Record from inside the cabin without placing a device under the vehicle.
Do not touch or crawl beneath a hot or unsupported vehicle.
Record reviewed in the source on August 2, 2026. Confirm the current document and VIN instructions before arranging work.
How we check a problem · All records for the 2019 Lexus RX 350