2021 Mercedes Benz S Class Recalls, Issues & Maintenance

The 2021 Mercedes Benz S Class has no open NHTSA recalls. Owners report 6 recurring issue clusters, led by “21-inch wheel rim cracking and tire blowouts.” Mercedes-Benz alternates two service events: Service A (oil, filter, inspection) at roughly 10,000 miles or 1 year, then Service B (Service A plus brake fluid, cabin filter, and deeper checks) at roughly 20,000 miles or 2 years — the ASSYST Plus counter in the cluster tells you which is due. Oil must carry the MB-Approval number your engine specifies (commonly 229.5, or 229.71 for newer 0W-20 engines); 'meets or exceeds' marketing language is not an approval. Electric EQB and EQS models keep the A/B rhythm for inspections, brake fluid, and cabin filters — just without oil.

No open recalls on file. NHTSA lists no unrepaired safety recalls for this year, make and model. A recall can be issued at any time, and a specific car can still have one open — check yours by VIN at nhtsa.gov/recalls.

Known issues for this vehicle

What drivers and federal regulators have officially reported about the 2021 Mercedes Benz S Class.

Reported to NHTSA

21-inch wheel rim cracking and tire blowouts

WHEELS

9 NHTSA complaints · 2022-07 → 2026-01

I purchased this vehicle used at a dealer in Virginia. I drove it home to Chelsea Alabama, outside Birmingham. After a couple of days, my front right tire went flat. I took it to the dealer and they said the flat tire was caused by a cracked rim and required both to be replaced.…
Owner report, NHTSA ODI #11643990
Three wheels had rim a total of eight cracks that lead to one tire unable to hold air. Loss of air in tire can lead to crash. Mercedes service inspected car after first crack was noticed by Discount Tire when they diagnosed deflation in tire
Owner report, NHTSA ODI #11710678

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Recall repair delays due to unavailable parts

ENGINE AND ENGINE COOLING

8 NHTSA complaints · 2021-12 → 2026-02

The contact owns a 2021 Mercedes-Benz S580. The contact received notification of NHTSA Campaign Number: 24V704000 (ENGINE AND ENGINE COOLING); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of…
Owner report, NHTSA ODI #11631798
The contact owns a 2021 Mercedes-Benz S580. The contact received a notification for NHTSA Campaign Number: 21V843000 (Engine and Engine Cooling) however, the part to do the recall repair was unavailable. The dealer had been notified about the recall; however, the contact was…
Owner report, NHTSA ODI #11443625

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Forward camera and ADAS system unavailability

LANE DEPARTURE: ASSIST, LANE DEPARTURE: WARNING, FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL

4 NHTSA complaints · 2024-04 → 2025-01

Every Mercedes Benz manufactured in 2021 has a defective hood lens which prevents the adaptive driver assistance system from working properly. You can have it on and it will work intermittently which can easily cause a major crash. Mercedes Benz says the part is not available in…
Owner report, NHTSA ODI #11591956
While on the freeway, going approximately 70 mph, the vehicles onboard cameras all failed and I got a warning that said “camera dirty/unavailable/traffic sign assist currently unavailable”. Because of this failure, I almost crashed the car in Front of me
Owner report, NHTSA ODI #11636844

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12V battery drain and electrical system warnings

ELECTRICAL SYSTEM, POWER TRAIN, FUEL/PROPULSION SYSTEM

4 NHTSA complaints · 2021-11 → 2022-07

Issue: STARTER BATTERY Repetitive online and dashboard screen message notices stating, "BATTERY CHARGE Status Critical," at all hours of day and night requesting immediate 30-60-min. of driving or car will not start. Have had to wake up from nightime sleep to drive car in…
Owner report, NHTSA ODI #11449211
The 12-volt battery gives CRITICAL CHARGE notifications constantly. Incident: Dry pavement, 400-mile, January winter night, highway driving in Wisconsin Northwoods at posted 70 mph; some with cruise control, some without cruise control. Seat belt was in use. On four…
Owner report, NHTSA ODI #11449057

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Forward collision avoidance unintended brake activation

SERVICE BRAKES, ELECTRICAL SYSTEM, FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING

3 NHTSA complaints · 2021-12 → 2023-08

Driving on highway at about 50 mph when the brakes suddenly slammed on and brought car to a sudden, near stop. The stop was so sudden our seatbelts engaged and we thought we were struck in the rear by another car. Electrical module issues that cause battery to drain while…
Owner report, NHTSA ODI #11501439
The contact stated that while driving at 50 MPH and attempting to accelerate, the vehicle inadvertently activated the Forward Collision Avoidance feature and briefly applied the brakes hard enough for the ABS to be activated. The contact stated that there were no objects near or…
Owner report, NHTSA ODI #11540188

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Cruise control unintended speed changes

POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE:SOFTWARE, VEHICLE SPEED CONTROL:CRUISE CONTROL

2 NHTSA complaints · 2021-11 → 2022-01

The contact stated while driving at 60 MPH, the contact pressed a button on the steering wheel to engage the cruise control function on the vehicle. The contact stated when driving past a mileage sign stating 40 MPH, the vehicle suddenly reduce in speed to 40 MPH, while the…
Owner report, NHTSA ODI #11442018
On four occasions, car independently, without any warning, dropped from 70 mph to 35 mph, projecting me forward. No reduction in speed signage No small town drive through. With car and semi-truck traffic behind me, luckily no rear end collisions, injury or death occurred
Owner report, NHTSA ODI #11449057

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Source: NHTSA Office of Defects Investigation (ODI). Complaint data refreshed Sep 17, 2026. Investigation data refreshed Sep 17, 2026.

We display NHTSA's record with attribution; we don't editorialize on what these complaints mean for any specific vehicle.

Essential maintenance

Critical for safety and preventing major damage

Service A — Oil & Filter + Inspection

Every 10,000 mi

Every 10,000 miles or 12 months: oil and filter with MB-Approved oil, fluid top-offs, tire check, and inspection. AMG models driven hard: many owners service at 5,000-7,500 miles.

Estimated cost — typical U.S. ranges

Dealer

~$120–$160

Shop

~$85–$115

DIY

~$25–$55

Full synthetic costs more than conventional. 5-quart 0W-20 + filter is the typical bill.

Service B — Major Inspection

Every 20,000 mi

Every 20,000 miles or 2 years, alternating with Service A: everything in A plus brake-fluid replacement, cabin filter, and a deeper multi-point inspection of brakes, suspension, and driveline.

Estimated cost — typical U.S. ranges

Dealer

~$85

Shop

~$60

DIY

Free

Most shops do this free with any paid service. A flashlight and 10 minutes covers the basics yourself.

Tire Rotation

Every 10,000 mi

Rotate at every Service A where the tire sizes allow. Many AMG and 4MATIC+ models run staggered widths that can't rotate front-to-rear — check your spec before paying for a rotation.

Estimated cost — typical U.S. ranges

Dealer

~$85

Shop

~$60

DIY

Free

Often free at the shop where you bought the tires — worth asking before paying.

Brake Inspection

Every 10,000 mi

Checked at every A/B service via electronic pad-wear sensors. Replace sensors with pads. Heavy EQS models wear pads slowly (regen braking) but rotors can corrode from disuse — an inspection catches that.

Estimated cost — typical U.S. ranges

Dealer

~$85

Shop

~$60

DIY

Free

Most shops do this free as a courtesy with any service. Don't pay separately if you can avoid it.

Brake Fluid

Every 20,000 mi

Replaced every 2 years as part of Service B — Mercedes schedules it on time, not miles, because DOT 4 fluid absorbs moisture regardless of driving.

Estimated cost — typical U.S. ranges

Dealer

~$180–$200

Shop

~$125–$140

DIY

~$10–$25

DOT 3 or 4 — match the cap. Vacuum bleeders make this a one-person DIY.

Important maintenance

Keeps your vehicle running smoothly and efficiently

Automatic Transmission Fluid (7G / 9G-Tronic)

Every 70,000 mi

Mercedes specifies fluid and filter service around 70,000 miles on most 7G- and 9G-Tronic gearboxes — check your year's sheet. Use only the MB-spec fluid for your transmission code; independent specialists often service at 60,000 on hard-driven cars.

Estimated cost — typical U.S. ranges

Dealer

~$330–$500

Shop

~$235–$355

DIY

~$60–$180

Some sealed transmissions have no dipstick — fill is precise and best left to a shop. Many drivers can still DIY drain-and-fill.

Spark Plugs

Every 60,000 mi

Most modern MB gas engines: plugs around 60,000 miles — AMG engines often sooner. Check your engine's sheet; twin-turbo V8 plug jobs are labor-heavy, so pair with other scheduled work.

Estimated cost — typical U.S. ranges

Dealer

~$285–$390

Shop

~$200–$275

DIY

~$25–$100

Iridium plugs cost more but last 100k+ miles. V6/V8 access varies wildly — some are tough.

Engine Air Filter

Every 40,000 mi

Replace around every 40,000 miles (twin-filter setups on V6/V8 engines double the parts bill). Inspected at every Service B.

Estimated cost — typical U.S. ranges

Dealer

~$60–$95

Shop

~$45–$70

DIY

~$15–$40

5-minute job on most cars; the airbox lid usually has clips, no tools needed.

Recommended maintenance

Extends the life of your vehicle and improves comfort

Combination / Dust Filter

Every 20,000 mi

Replaced with every Service B. Models with the ENERGIZING air package use a higher-grade filter — priced accordingly.

Estimated cost — typical U.S. ranges

Dealer

~$60–$95

Shop

~$45–$70

DIY

~$15–$40

Usually behind the glovebox. Shops charge labor for a 10-minute job — easy DIY win.

Engine Coolant

On condition / lifetime

MB-spec coolant is long-life (typically ~10 years / 150,000 miles on the sheet). Refresh only with MB 325/326-spec coolant — the wrong chemistry attacks aluminum and head gaskets.

Estimated cost — typical U.S. ranges

Dealer

~$285–$330

Shop

~$200–$235

DIY

~$25–$60

Use the manufacturer-specified coolant — wrong color/chemistry can damage the cooling system.

12V & Auxiliary Battery

Every 25,000 mi

Test annually after year 3. Most modern Mercedes carry a second auxiliary battery; a weak one triggers cascading warning messages long before a no-start. EQ models also depend on the 12V system to boot.

Estimated cost — typical U.S. ranges

Dealer

~$225–$390

Shop

~$160–$280

DIY

~$130–$250

Most auto-parts stores test and install batteries free with purchase. Skip the dealer markup.

Fatal crash history & reported problems

Occupant deaths in fatal crashes (FARS)

1 crashes 2010–2024

FARS counts every occupant death in a fatal crash, whatever the cause — it does not mean the vehicle was at fault or defective. Counts are not adjusted for how many of each vehicle are on the road. How to read this number

Owner-reported problem signals

Separate from the federal fatality data above: complaints owners filed with NHTSA about this year and model. These are reports of problems, unverified, and are counted here only as signals.

2

complaints mentioning a crash

0

complaints mentioning a fire

Reviewed known issues for this vehicle

Typical U.S. ranges. Actual quotes vary by shop, parts choice, and vehicle condition.

How we estimate: Dealer = OEM parts × 1.4 + labor × $165/hr. Shop = parts + labor × $115/hr. DIY = parts only.

This maintenance schedule for the 2021 Mercedes Benz S Class reflects Mercedes-Benz's published service intervals and the ASSYST Plus (Service A / Service B) system. Your actual service needs may vary based on driving conditions, climate, and vehicle usage. Always consult your owner's manual for model-specific recommendations.