2018 Mercedes-Benz C300 Problems & Complaints

Most common 2018 Mercedes-Benz C300 problems

• Engine & cooling~54,000 miles
  3733%
• Other / not specified~30,000 miles
  2321%
• Body & structure~49,000 miles
  1816%
• Steering~57,000 miles
  1312%
• Electrical system~53,000 miles
  1110%
• Fuel & propulsion system~62,000 miles
  109%
• Air bags~10,000 miles
  55%
• Driver assistance~5,000 miles
  55%
• Equipment & accessories~85,000 miles
  55%
• Windows, wipers & sunroof~70,000 miles
  44%
• Lights~53,000 miles
  33%
• Wheels & tires~16,000 miles
  33%
• Brakes~75,000 miles
  22%
• Transmission & drivetrain~62,000 miles
  22%
• Seat belts~59,000 miles
  22%
• Seats~75,000 miles
  11%
• Suspension
  11%

Share of the 111 complaints; one complaint can involve more than one system. "~" is the median mileage when the problem started.

Mercedes-Benz C300 complaints by model year

Best C300 years: 2014, 2021, 2020. Years to avoid: 2009, 2008. Compare all years →

2018 Mercedes-Benz C300 recalls (18)

NHTSA defect investigations

Federal safety investigators have looked into 2 possible defects involving the 2018 Mercedes-Benz C300:

What 2018 Mercedes-Benz C300 owners say

Engine & cooling all 37 →

The contact owns a 2018 Mercedes-Benz C300. The contact stated while driving 35 MPH, there was white smoke coming from exhaust. The contact stated that the check engine warning light illuminated. The contact stated that after turning off the vehicle the smoke cleared. The vehicle was towed to dealer but was not diagnosed or repaired. The manufacturer was notified of the failure. The approximate failure mileage was 54,000.

CYLINDER 1 SPARK PLUGS IS DAMAGED DUE TO PISTON DAMAGE, HOLE IN PISTON. IF EXTRA DAMAGE IS FOUND ON TEAR DOWN, COMPLETE ENGINE REPLACEMENT. This is direct from the repair facilities reports. While driving my 2018 C-300 there was smoking out of tail pipe, a rough vibration, hard to control the vehicle and it was starting to lose power. Not a good situation, had to pull over and have vehicle towed to the dealership. Worst part is this is a vehicle used to transport my 5 children to and from school and activities. My 16 year old also drives this vehicle, had he been driving this with this happening to him, the outcome could have been catastrophic. Vehicle has been inspected by 2 facilities; first was a certified Mercedes Benz repair facility and the second was the service dept. of the Mercedes Benz dealership I have serviced at for over 10 years. …

Body & structure

The contact owns a 2018 Mercedes-Benz C300. The contact stated that while driving approximately 60 MPH, a part of the panoramic roof towards the driver's side detached from the vehicle. The contact pulled over to inspect the vehicle. The part was no longer attached, and the contact had to continue driving. The failure caused additional electrical failures due to water entering the cabin of the vehicle. The contact stated that the sunroof failed to open, and the infotainment center was inoperable. The contact found information on NHTSA Campaign Number: 23V854000 (Structure); however, the VIN was not included. The vehicle was taken to the dealer, who related the failure to the recall; however, the vehicle could not be repaired under the recall because the VIN was not available. The vehicle was not repaired. The manufacturer was informed of the failure and opened a case. …

The contact owns a 2018 Mercedes-Benz C-300. The contact stated that while driving 70 MPH South on the interstate towards Miami, the front panel detached without warning. The contact pulled over to inspect the vehicle and became aware that the panel between the windshield and sunroof had detached. The contact stated that water started entering the vehicle from several areas. The sunroof was inoperable. The contact called the insurance company. The contact associated the failure with NHTSA Campaign Number: 23V854000 (Structure). The local dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted, but no additional assistance was provided. The approximate failure mileage was 83,000.

Steering

While driving in a curved onramp connecting from one street to another the vehicle experienced a complete loss of steering ability which resulted in the vehicle continuing to move straight, off the pavement, and into a wall. The vehicle bounced off of the wall and loss of steering ability continued and the vehicle could not be controlled, crossed the road, went over a guardrail, and down an embankment until it came to a stop (approx 100ft). The vehicle engine never turned off until it came to a stop at which point the vehicle was manually turned off. No airbags deployed. There were no warning lights or signals of failing components prior to the loss of steering. An initial review by the body shop states that the vehicle is a total loss. The vehicle has been meticulously dealer maintained since the time of delivery as a new vehicle. …

The contact owns a 2018 Mercedes-Benz C300. While driving at various speeds, the contact could hear an abnormal sound from the transmission. The vehicle was taken to a local independent mechanic where it was diagnosed that the rack and pinion needed to be replaced. The vehicle was not repaired. The vehicle was then taken to a local dealer for diagnosis, but the failure could not be replicated. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 57,000.

2018 Mercedes-Benz C300 engines & fuel economy

EPA ratings. Class: Compact car.