Owner complaints, recalls, fuel economy and safety ratings from public NHTSA and EPA data, updated Oct 17, 2026.
Fuel economy
22–26 mpgcombined; city 19–23, highway 28–32; every version of this model year
Five years of fuel
$15,480–$18,290U.S. average; Ohio $14,580–$17,240 at local prices; every version of this model year; fuel only, not other costs of owning it; 15,000 miles a year, at EIA fuel prices for the week of Oct 12, 2026
NHTSA overall safety rating
Not ratedNHTSA has no overall rating for this year
Owners have filed 4 complaints with NHTSA about the 2015 SLK-Class. These are unverified owner reports, counted by the part of the car they name; one complaint can name several parts. Counts aren't adjusted for how many were sold, so they don't show how reliable a car is.
Complaints by part of the car
Part
Complaints
Crashes
Fires
Injuries
Fuel/propulsion system
1
0
0
0
Service brakes
1
0
0
0
Structure
1
0
0
0
Unknown or other
1
0
0
0
Complaints by model year
Newer years have had less time to collect complaints, and counts aren't adjusted for sales, so a shorter bar doesn't mean a more reliable year.
NHTSA lists 3 recall campaigns for the 2015 SLK-Class over its history. Campaigns are matched by model and year, so each one may apply to a given car, and its repair may already be done: check a VIN on NHTSA's recall lookup for the open recalls on that exact car.
Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2013-2017 vehicles due to a software fault that may cause the date and time for the emergency call system (eCall) to differ from the actual date and time, potentially relaying an inaccurate vehicle location. For a full list of the affected models visit: https://static.nhtsa.gov/odi/rcl/2019/RMISC-19V787-4620.pdf
Risk: An inaccurate vehicle location may delay emergency responders, increasing the risk of injury.
Remedy: MBUSA has initiated an Over the Air (OTA) remote update. MBUSA will also notify owners, and dealers will check software for a successful OTA or update the communication module software as needed, free of charge. The recall began December 23, 2019. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2019120008.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2015 SLK 250, 2016 SLK 350, 2016-2017 SLC 300, and 2017 SLC 43 AMG vehicles. In these vehicles, the electronic stability control (ESC) system software may incorrectly keep the brakes slightly applied.
Risk: If brake pads are constantly applied over long periods of driving, the brake components may heat up, affecting braking performance and increasing the risk of a crash. Additionally, the dragging brakes may overheat, increasing the risk of a fire.
Remedy: MBUSA will notify owners, and dealers will update the software for the ESC system, free of charge. The recall began June 9, 2017. Owners may contact MBUSA customer service at 1-800-367-6372.
Mercedes-Benz USA, LLC (MBUSA) is recalling certain model year 2016 SLK300, SLK350, SL400, SL550, and SL63 AMG vehicles manufactured from June 29, 2015, through July 13, 2015. The affected vehicles are equipped with low-beam headlights that may have been aimed incorrectly during vehicle production. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 108, "Lamps, Reflective Devices, and Associated Equipment."
Risk: Improperly adjusted low-beam headlights may reduce the driver's visibility, increasing the risk of a crash.
Remedy: MBUSA will notify owners, and dealers will inspect and if necessary adjust the headlamps, free of charge. The recall began on July 22, 2016. Owners may contact MBUSA customer service at 1-800-367-6372.
Carmakers sent NHTSA 77 service bulletins and notices that cover the 2015 SLK-Class, the latest on Sep 22, 2026. They tell dealers how to fix known issues.
The parts they mention most: electrical system (17), exterior lighting (13), equipment (9), service brakes (8), structure (8).
NHTSA defect investigations
Opening an investigation isn't a finding of a defect. Outcomes are as NHTSA's summary states them. A recall is shown as an investigation's outcome only where NHTSA's summary names it; other recalls NHTSA's file lists with it are marked as listed, not caused.
Investigation
Part
Opened
Status
Engineering analysis EA21002 Desiccated Air Bag Inflator Rupture · covers 37 makes
The owner's manual gives the oil and how often to change it. We show oil facts only once we've checked them against the manual, and we haven't yet for the 2015 SLK-Class.
EPA class: two seaters. EPA greenhouse gas score: 5–6 out of 10. Each version EPA tested:
Swipe the table sideways for more columns.
Version
Engine
Transmission
Fuel
City / hwy / comb
SLK250 Rear-Wheel Drive
1.8 L, 4 cyl, turbo
Automatic 7-spd
Premium Gasoline
23 / 32 / 26
SLK250 Rear-Wheel Drive
1.8 L, 4 cyl, turbo
Manual 6-spd
Premium Gasoline
22 / 32 / 26
SLK350 Rear-Wheel Drive
3.5 L, 6 cyl
Automatic 7-spd
Premium Gasoline
21 / 28 / 24
SLK55 AMG Rear-Wheel Drive
5.5 L, 8 cyl
Automatic 7-spd
Premium Gasoline
19 / 28 / 22
Sources and dates
U.S. EPA fuel economy data, file of Sep 29, 2026
NHTSA owner complaints, file of Oct 17, 2026
NHTSA recalls, file of Oct 17, 2026
NHTSA manufacturer communications, file of Oct 17, 2026
NHTSA defect investigations, file of Oct 17, 2026
NHTSA 5-Star Safety Ratings, file of Aug 7, 2026
U.S. Energy Information Administration, file of Oct 12, 2026
Fuel cost: EPA mpg with fuel prices for the week of Oct 12, 2026 and electricity prices for Jul 2026. Source: U.S. Energy Information Administration (Oct 2026). Complaints are unverified reports owners filed with NHTSA. About the data