Here is a list of undercar Technical Service Bulletins (TSBs) posted to the National Highway Traffic Safety Administration’s ODI database in the first quarter of 2026. These bulletins apply to a wide range of vehicles, include diagnostic information, and can be useful to technicians at independent repair shops.
Audi
Creaking/Squeaking Noises from the Front End on Uneven Roads
Link: https://static.nhtsa.gov/odi/tsbs/2026/MC-11028480-0001.pdf
Audi has issued TSB 2043424/19 for a front-end noise condition on several A3-based platforms and the Q3. The bulletin covers vehicles where customers report a creaking or squeaking noise from the left or right front area when driving on uneven roads. Audi identifies the issue as a suspension-related noise, not a steering or brake problem.
Vehicles covered
- 2015-2020, 2022-2025 Audi A3
- 2015-2020, 2022-2025 Audi S3
- 2015-2019 Audi A3 Cabriolet
- 2016-2018 Audi A3 Sportback e-tron
- 2017-2020, 2022-2025 Audi RS 3
- 2019-2025 Audi Q3
According to Audi, the condition is a creaking or squeaking noise from the left front or right front area when the vehicle is driven on uneven roads. The cause is tied to the rear bonded rubber bushings of the front lower control arms. Earlier versions of the bulletin describe these bushings as having kidney-shaped slits, which can generate the noise under suspension movement.
Audi’s correction is to confirm the complaint and then service the affected front lower control arm rear bushings rather than replacing unrelated components. Bulletin summaries indicate the repair involves applying lithium grease to the rear bonded rubber bushings to eliminate the noise in the areas shown in the figure below.
Put lithium grease in these areas.
Audi
Droning/Vibrations During Tight Turns
Link: https://static.nhtsa.gov/odi/tsbs/2026/MC-11028433-0001.pdf
Audi has issued Technical Service Bulletin 2059057/13, released Jan. 22, 2026, for vehicles equipped with Quattro Ultra, PR number GH4. The models covered include:
- Audi A4, A4 Allroad (2017-2025)
- Audi S4, A5, A5 Cabriolet, A5 Sportback, S5, S5 Cabriolet, S5 Sportback, RS 5, Q5, SQ5 (2018-2025)
- Audi RS 5, A6, A7 (2019-2025)
- Audi A6 Allroad, S6, S7, Q5 e quattro (2020-2025)
- Audi RS 6 Avant, RS 7, Q5 Sportback, SQ5 Sportback (2021-2025)
- Audi A7 e quattro (2021-2022)
Concern/Symptom
The customer may report vibrations, humming, droning or rubbing noises that can be heard and/or felt in the vehicle interior or rear seat area during very tight turns or with the steering wheel fully turned. The bulletin says the concern must be reproducible, or the noise must be able to be assigned to the all-wheel-drive clutch, propeller shaft or rear differential. It also notes there should be no DTCs stored in the transmission control module or the all-wheel-drive control module.
Cause
According to Audi, the condition is caused by the different operating speeds between the front axle differential and the rear final drive. Under very tight cornering with four-wheel-drive clutch 1 closed, the system can produce varying degrees of humming, drumming, vibration or binding. Audi lists no production solution in the bulletin.
Correction
The bulletin instructs technicians to first reproduce and clearly assign the concern to this TSB. Audi then directs the repair in sequence, beginning with checking vehicle history, confirming transmission temperature, and using ODIS Guided Functions to read and upload measured values. The service path includes checking the four-wheel-drive clutch oil, performing the oil replacement procedure, and, if the condition remains after the required drive cycle, replacing the all-wheel-drive clutch/four-wheel coupling as outlined in the bulletin.
BMW
Rear Axle Wheel Bearing Complaints
Link: https://static.nhtsa.gov/odi/tsbs/2026/MC-11030056-0001.pdf
BMW Service Information Bulletin SIB 33 01 26 addresses rear axle wheel bearing complaints on certain X models built within the listed production ranges. The bulletin covers both customer noise complaints and fault memory entries tied to the rear wheel speed sensor area. BMW says the issue can show up as a humming or clicking noise from the rear axle, or as a Dynamic Stability Control warning with related faults stored in the Integrated Brake module.
Models covered
- BMW X2 Sports Activity Coupe (U10), September 2022 to April 3, 2025
- BMW X1 Sports Activity Vehicle (U11), November 2023 to April 3, 2025
Concern
BMW lists two possible complaints. The first is a humming or clicking noise heard from the rear axle in the 15-65 mph speed range, with the noise potentially becoming more noticeable depending on road speed. The second is a Dynamic Stability Control malfunction indicator lamp and/or related Check Control message. When fault memory is checked, technicians may find these Integrated Brake module faults:
4809B7 rear left wheel speed sensor tooth missing,
4809C2 rear right wheel speed sensor tooth missing,
480AB4 rear right wheel speed sensor noise monitoring, and
480AAD rear left wheel speed sensor noise monitoring.
Cause
For noise complaints, BMW says insufficient protection can allow water to enter directly into the wheel bearing, which can also lead to corrosion of the wheel bearing inner race. For fault memory entries, the cause is listed as foreign particles and/or corrosion at the interface to the wheel speed sensor.
Correction
BMW’s correction is straightforward: replace both rear axle wheel bearings. For noise complaints, replace both rear wheel bearings following repair instruction REP 33 41 180. For fault-related complaints, first perform a vehicle test and confirm one of the listed Integrated Brake fault codes is present, then replace both rear axle wheel bearings using the same repair procedure. For technicians, the important takeaway is that rear axle humming, clicking, or specific rear wheel speed sensor faults on these vehicles should direct attention to the rear wheel bearings and related corrosion or contamination issues before chasing other chassis or brake system components.
BMW
Rear Suspension Struts Rattle When Driving Over Rough Road Surface
LINK: https://static.nhtsa.gov/odi/tsbs/2026/MC-11029068-0001.pdf
BMW Service Information Bulletin SIB 33 01 25 addresses a rear suspension noise concern on certain 2021-2022 BMW 2-Series Coupe (G42) models equipped with the B58D engine. The complaint is a rattling noise from the luggage compartment area when the vehicle is driven over rough road surfaces.
According to BMW, the cause is function-related noises from the dampening components in the rear suspension. This means the sound is tied to the operation of the affected parts rather than an unrelated trim or cargo compartment issue.
For technicians diagnosing this complaint, BMW’s recommended repair is to replace the support bearings, auxiliary shock absorbers, stabilizer and stabilizer supports with the updated parts listed in the bulletin.
If a 2021-2022 G42 arrives with a rear rattle that seems to come from the trunk area on rough roads, the repair path should focus on the rear suspension dampening components rather than interior panels or loose luggage compartment hardware.
GM
Unable to Perform GDS2 Automated Bleed After Master Cylinder Replacement
https://static.nhtsa.gov/odi/tsbs/2026/MC-11028935-0001.pdf
GM has issued Bulletin No. PIT6477B covering a brake service issue on select 2026 full-size SUVs. According to the bulletin, some technicians may encounter an error screen when attempting to perform the GDS2 automated brake bleed procedure after replacing the master cylinder. The condition is tied to a software anomaly in GDS2, not a hydraulic or component failure.
Vehicles Covered
- 2026 Cadillac Escalade
- 2026 Cadillac Escalade ESV
- 2026 Chevrolet Suburban
- 2026 Chevrolet Tahoe
- 2026 GMC Yukon
- 2026 GMC Yukon XL
The condition appears after master cylinder replacement, when the technician attempts to run the automated bleed function. Because the issue is caused by GDS2 software, the recommended fix is to confirm the scan tool software is current before continuing with the diagnosis.
GM recommends beginning with Automated Brake Bleed. If that procedure completes successfully, no further action is needed. If it does not complete successfully, technicians should then select Modified Automated Brake Bleed, which includes the updated fix. For affected vehicles, checking software version first can prevent wasted diagnostic time and avoid unnecessary parts replacement.
Honda
Pop Or Clunk From The Front Suspension While Driving Over A Bump After Turning
Link: https://static.nhtsa.gov/odi/tsbs/2026/MC-11028517-0001.pdf
Honda Service Bulletin 07-078 covers a front suspension noise on these vehicles:
- 2006-2010 Honda Civic 2-door
- 2006-2010 Honda Civic 4-door
- 2011 Honda Civic 2-door
- 2011 Honda Civic 2-door Si
- 2011 Honda Civic 4-door
- 2011 Honda Civic 4-door Si
Screenshot
The condition is a pop or clunk from the front suspension when driving over bumps, usually after a tight, full-lock turn. Honda’s bulletin identifies the fix as a repair to the front bump stops. The recommended correction is to replace both front bump stops and glue them in place to prevent the noise from returning.
Porsche
Jangling Noises from the Front Axle Area when Driving over Uneven Surfaces Porsche Active Suspension Management (PASM) and Steel Suspension
Link: https://static.nhtsa.gov/odi/tsbs/2026/MC-11028576-0001.pdf
Porsche has identified a front axle noise condition on certain Macan models equipped with Porsche Active Suspension Management and steel suspension. The concern involves a customer complaint of a jangling, knocking or tapping noise from the front axle when driving over uneven road surfaces. In some cases, the noise may sound like a loose or worn suspension component, but the bulletin says that is not always the case.
Vehicles covered
- 2024 Porsche Macan (XAB)
- 2025 Porsche Macan (XAB)
According to Porsche, the condition can be caused by the anti-dive function built into the front suspension system. This feature is designed to reduce front-end dive during braking. Under certain driving conditions, especially when the brakes are released just before the vehicle crosses an obstacle such as a road edge or speed bump, the resulting noise can be misinterpreted as a component defect. Porsche notes that if the noise is caused by the anti-dive function, there is no failed part and the condition is considered normal and safe.
To confirm the cause, Porsche recommends duplicating the complaint in two different driving situations. In the first test, approach an obstacle at about 40 km/h (25 mph), apply light brake pressure to slow the vehicle so the obstacle is crossed at about 20 km/h (12 mph), then release the brake quickly immediately before the obstacle. If the noise occurs here, it may be related to the anti-dive function.
In the second test, approach the same type of obstacle slowly, again apply light brake pressure, but release the brake well before the obstacle. If the noise is absent in this second test and only appears in the first, Porsche says the sound is a normal characteristic of the system.
If the noise is present in both driving situations, technicians should not blame the anti-dive function. In that case, normal suspension and front axle troubleshooting should continue. The key recommendation is to verify the operating conditions before replacing parts, since this bulletin describes a characteristic that may be normal rather than a defect.
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