Factory specifications, fluid capacities, torque values, EPA fuel economy and the federal safety record for the 2021 C300.
The 2021 Mercedes C300 features an engine that holds 6.3 qt of oil, with the factory specifying viscosities of 0W‑20, 0W‑30 or 0W‑40. The model year builds on the C‑Class’s established reputation for dependable engineering, reflecting a reliability record that remains consistent across the lineup. Its design integrates efficiency and refinement, marking a steady chapter in the vehicle’s evolution.
Fluid capacities, tune-up values and fuel economy at a glance.
Replacement part sizes and factory part numbers — battery, bulbs, filters and belts.
From the factory this vehicle uses OE oil filter 2701800109. Each part links to every other vehicle that shares it, so a part you already stock may fit more of your fleet than you'd expect.
| Engine oil filter | 2701800109 |
| Engine air filter | 2640940100 |
| Spark plug | 0001590500 |
| Battery | 0019828108 alt 0019828008 |
| Front wiper blades | 2058204503 |
| Thermostat | 2642003901 |
| Cabin air filter | 1668300218 |
Engine, drivetrain, dimensions and economy.
| Overall length | 184.6 in |
| Overall width | 71.3 in |
| Overall height | 55.1 in |
| Wheelbase | 111.8 in |
| Curb weight | 3979 lb |
| Track (front / rear) | 61.4 / 61 in |
Capacities, torques and tune-up values from the factory service manual.
This engine holds 6.3 qt of 0W-20 / 0W-30 / 0W-40 engine oil, DOT 4 brake fluid. Torque the oil drain plug to Use a new seal: 30.0 ft-lbs. The firing order is 1-3-4-2.
| Automatic Transmission Fluid | MB Sheet 236.17 |
| Automatic Transmission Fluid Capacity | 10.5 qt |
| Brake Fluid | DOT 4 |
| Engine Coolant | Coolant listed on either MB 325.6 |
| Engine Oil Capacity | 6.3 qt |
| Engine Oil Capacity | 6.3 qt |
| Transfer Case Fluid | Mercedes Benz P/N 001989780309 |
| Transfer Case Fluid Capacity | 0.73 qt |
| Crankshaft Pulley and/or Damper Bolts | Step 1 148.0 ft-lbs, Step 2: 180° ft-lbs |
| Cylinder Head Instructions | Use new bolts only. |
| Engine Oil Pan Drain Plug | Use a new seal: 30.0 ft-lbs |
| Differential Fill Plug | Front: 18.0 ft-lbs; Rear: 37.0 ft-lbs |
| Differential drain Plug | Front: 15.0 ft-lbs; Rear: 37.0 ft-lbs |
| Transfer Case Fill Plug | 10.0 ft-lbs |
| Transfer Case Drain Plug | 18.0 ft-lbs |
| Cylinder Firing Order | 1-3-4-2 |
| Spark Plug Manufacturer | Mercedes-Benz |
| Spark Plug Gap | 0.028 in |
| Spark Plug Torque | 17.0 ft-lbs |
| Refrigerant | R1234yf |
| Refrigerant Capacity | 1.39 lbs |
| Oil Capacity | 2.80 oz |
| Minimum Pad Thickness | 0.079" in |
| 1 | Bolts 1-10 | 7.4 ft. lbs |
Owner-reported issues, recalls, investigations and service bulletins on record with NHTSA — an unfiltered look at what owners actually experience.
Showing 2 of 2 campaigns on record for this vehicle.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 C300 Cabriolet, C43 AMG Cabriolet, C63 AMG Cabriolet, C63 AMG S Cabriolet, E450 Cabriolet, and E53 AMG Cabriolet vehicles. The rear headrests may be incorrectly… Remedy: Dealers will inspect the rear seatback guide bushings and replace them if necessary, free of charge. Owner notification letters were mailed July 16, 2021. Owners may contact MBUSA…
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 C-Class, E-Class, E-Class Coupe and Convertible, GLC, CLS, AMG GT 4-door Coupe and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle… Remedy: MBUSA will notify owners, and dealers will replace the seat position switches, free of charge. Owner letters were mailed May 21, 2021. Owners may contact MBUSA customer service at…
The most common OBD-II codes for this vehicle's emissions system. These are standardized SAE J2012 definitions, not vehicle-specific fault reports.
Decode factory build data for a specific vehicle by VIN.
Find every vehicle that shares this one's battery, bulbs, oil capacity, platform or parts.
Cross-vehicle references for the kinds of data on this page.
6.3 qt of 0W-20, 0W-30, 0W-40; Above 23°F: 20W-40, 20W-50; Above 5°F: 15W-30, 15W-40, 15W-50; Above -4°F: 10W-30, 10W-40, 10W-50, 10W-60; Above -13°F: 5W-30, 5W-40, 5W-50, per the factory manual.
NHTSA lists 2 recall campaign(s) for this model year. Check your specific vehicle by VIN.