HomeAboutPromiseReportsVehiclesLookupContactTry It Now
English|Español
Wrench.ProWrench.Pro
Wrench.ProWrench.Pro

Built for drivers. We work for the person paying the repair bill. Read our promise.

HomeAboutPromiseReportsLookupContactBrowse vehiclesOwn a shop? Claim your listing →
© 2026 Wrench.Pro. All rights reserved.
Credits
  1. Home
  2. ›Vehicles
  3. ›2018
  4. ›Mercedes Benz
  5. ›Mercedes Benz Cla Class

2018 Mercedes Benz Cla Class Maintenance Schedule

Manufacturer-recommended service intervals for the ASSYST Plus (Service A / Service B) and open recall alerts for your 2018 Mercedes Benz Cla Class.

Make this page yours

Personalize for your car and your area

ZIP unlocks trusted shops near you. Mileage unlocks personalized service due dates. Either or both — your call.

Go

Your ZIP stays with us. We share your city with shops, never your ZIP. Read our Promise →

RecallsFull scheduleKnown issues7

How Mercedes-Benz schedules service: ASSYST Plus (Service A / Service B)

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.

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.

Known issues for this vehicle

What drivers and federal regulators have officially reported about the 2018 Mercedes Benz Cla Class.

Reported to NHTSA

Instrument cluster blackout while driving

ELECTRICAL SYSTEM

4 NHTSA complaints · 2024-01 → 2026-05

“The cluster panel lights that indicate speed, fuel, brakes, lights, turn signal, engine light, high beams and all other components of safety of car continue to black out altogether or flash on and off continuous while driving…”
— Owner report, NHTSA ODI #11564453
“Vehicle cluster lights go black while driving...dangerous due to no fuel gauge..no speed gauge... no speedometor..no seat belt warning and no blinkers to exit highway safely…”
— Owner report, NHTSA ODI #11573041

Read all complaints on NHTSA →

PCV valve fault with P052E code

ENGINE

4 NHTSA complaints · 2024-10 → 2025-08

“I am driving around 55K miles in this car, and my check engine light comes up. I head to a local place to get a code check. The guy looks it up and tells me this is pretty much with EVERY Mercedes CLA around that mile point..…”
— Owner report, NHTSA ODI #11622361
“Check engine code PO52E - Positive Crankcase Ventilation regulator valve performance. Needs to be recalled”
— Owner report, NHTSA ODI #11626114

Read all complaints on NHTSA →

Front roof panel detachment and water intrusion

STRUCTURE

6 NHTSA complaints · 2023-12 → 2026-05

“Within 2 weeks after purchasing this vehicle the front stationary roof panel flew off the car. I noticed it when I parked at work in the parking lot. I do not know where the panel is. I retraced my route and did not see it anywhere…”
— Owner report, NHTSA ODI #11639023
“The contact owns a 2018 Mercedes-Benz CLA250. The contact stated that while the vehicle was at the car wash, water entered through the overhead center console…”
— Owner report, NHTSA ODI #11638024

Read all complaints on NHTSA →

Communication recall repair part unavailable

ELECTRICAL SYSTEM, COMMUNICATION

3 NHTSA complaints · 2021-05 → 2021-09

“The contact owns a 2018 Mercedes-Benz AMG CLA45. The contact received notification of NHTSA Campaign Number: 21V058000 (Communication, Electrical System) however, the part to do the recall repair was unavailable…”
— Owner report, NHTSA ODI #11433044
“Manufacturer has not fixed the outstanding software safety recall in a timely fashion. I have contacted them over 10 times and no one has any idea when the software update will be sent and there is no one they can escalate the issue to…”
— Owner report, NHTSA ODI #11427487

Read all complaints on NHTSA →

Engine shutdown and neutral shift while driving

POWER TRAIN, ELECTRONIC STABILITY CONTROL (ESC), ENGINE

5 NHTSA complaints · 2017-09 → 2021-10

“AS I ACCELERATED OUT OF A LEFT TURN, THE ENGINE SUDDENLY SHUT OFF, THE TRANSMISSION SHIFTED INTO NEUTRAL, AND THE DASH INDICATED THAT THE VEHICLE WAS 'INOPERABLE'. I PULLED OVER AND TURNED OFF THE IGNITION. WHEN I ATTEMPTED TO RESTART, THE VEHICLE STARTED WITH NO ISSUES.”
— Owner report, NHTSA ODI #11029885
“I WAS DRIVING ON THE ACCESS ROAD GETTING READY TO MERGE ONTO THE HIGHWAY. I PROCEEDED ONTO THE HIGHWAY AND MADE IT INTO THE MIDDLE LANE GOING AROUND 60 MPH BUT SHORTLY AFTER MY CAR THREW ITSELF INTO NEUTRAL…”
— Owner report, NHTSA ODI #11143405

Read all complaints on NHTSA →

Clock spring failure and airbag warning

AIR BAGS

5 NHTSA complaints · 2023-09 → 2025-11

“The contact owns a 2018 Mercedes-Benz CLA250. The contact stated that while driving and turning the steering wheel to the left, there was an abnormal clicking sound coming from the vehicle…”
— Owner report, NHTSA ODI #11697599
“The contact owns a 2018 Mercedes-Benz CLA250. The contact stated that while driving at an undisclosed speed, the air bag warning light illuminated. Additionally, the steering wheel made a clicking sound while turning, and the mileage button on the steering wheel was inoperable…”
— Owner report, NHTSA ODI #11542118

Read all complaints on NHTSA →

Rear differential noise at low speed

POWER TRAIN

3 NHTSA complaints · 2023-06 → 2025-06

“My 2018 Mercedes-Benz CLA250 4MATIC is experiencing a knocking noise from the rear differential at low speeds. The issue poses potential driving hazards, including possible loss of control and increased wear on drivetrain components…”
— Owner report, NHTSA ODI #11612753
“When you start off at a slow speed, the rear end of the car starts making a knocking noise. We had it inspected by Mercedes-Benz and they said that it is the rear differential.”
— Owner report, NHTSA ODI #11669091

Read all complaints on NHTSA →

Issues on other model years

  • 2015 Mercedes Benz Cla Class →
  • 2016 Mercedes Benz Cla Class →
  • 2017 Mercedes Benz Cla Class →
  • 2019 Mercedes Benz Cla Class →
  • 2020 Mercedes Benz Cla Class →
  • 2021 Mercedes Benz Cla Class →

Source: NHTSA Office of Defects Investigation (ODI). Complaint data refreshed Jul 21, 2026. Investigation data refreshed Jul 21, 2026.

We display NHTSA's record with attribution; we don't editorialize on what these complaints mean for any specific 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 2018 Mercedes Benz Cla 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.

Check another vehicle →