Showing the 2018 Sonic FL. We haven't verified this trim's engine; the numbers below cover every version of this model year. Every version
Owner complaints, recalls, fuel economy and safety ratings from public NHTSA and EPA data, updated Oct 17, 2026.
Fuel economy
28–32 mpgcombined; city 25–28, highway 34–37; every version of this model year
Five years of fuel
$10,150–$11,600U.S. average; Ohio $9,070–$10,370 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's VIN data lists these trims for the 2018 Sonic. A trim's engine and numbers are shown as its own only where EPA names versions after the trim and no other version could be it; "seen with" means a source shows that engine on the trim, not that it was the only one. Recalls and complaints cover the whole model year: whether a recall applies to a car depends on its VIN, on NHTSA's recall lookup.
Owners have filed 15 complaints with NHTSA about the 2018 Sonic. 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
Electrical system
6
0
0
0
Engine
4
0
0
0
Seats
2
0
0
0
Unknown or other
2
0
0
0
Wheels
2
0
0
0
Air bags
1
0
0
0
Exterior lighting
1
0
0
0
Fuel system, gasoline
1
0
0
0
Fuel/propulsion system
1
0
0
0
Parking brake
1
0
0
0
Seat belts
1
0
0
0
Steering
1
0
0
0
1 more part
Visibility/wiper
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 1 recall campaign for the 2018 Sonic 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.
General Motors LLC (GM) is recalling certain 2018 Chevrolet Sonic vehicles. A joint in the driver's seat-back frame may not be properly welded, reducing the strength of the seat-back frame.
Risk: In the event of a rear-impact crash, the seat-back may fail, increasing the risk of injury.
Remedy: GM will notify owners, and dealers will replace the driver's seat-back, free of charge. The recall began June 28, 2018. Owners may contact Chevrolet customer service at 1-800-222-1020. GM's number for this recall is 18178.
Carmakers sent NHTSA 821 service bulletins and notices that cover the 2018 Sonic, the latest on Sep 26, 2026. They tell dealers how to fix known issues.
The parts they mention most: equipment (344), electrical system (150), engine and engine cooling (111), engine (83), unknown or other (76).
NHTSA hasn't opened a defect investigation that covers this model year.
Maintenance
Oil
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 2018 Sonic.
These are searches on those sites; we don't copy or check their listings. Your ZIP is used for these links and never kept.
Specs
EPA class: compact cars. EPA greenhouse gas score: 6–7 out of 10. Each version EPA tested:
Swipe the table sideways for more columns.
Version
Engine
Transmission
Fuel
City / hwy / comb
Sonic Front-Wheel Drive
1.4 L, 4 cyl, turbo
Manual 6-spd
Regular Gasoline
28 / 37 / 32
Sonic Front-Wheel Drive
1.4 L, 4 cyl, turbo
Automatic (S6)
Regular Gasoline
27 / 35 / 30
Sonic Front-Wheel Drive
1.8 L, 4 cyl
Manual 5-spd
Regular Gasoline
26 / 35 / 29
Sonic Front-Wheel Drive
1.8 L, 4 cyl
Automatic (S6)
Regular Gasoline
25 / 34 / 28
Sonic 5 Front-Wheel Drive
1.4 L, 4 cyl, turbo
Manual 6-spd
Regular Gasoline
28 / 37 / 32
Sonic 5 Front-Wheel Drive
1.4 L, 4 cyl, turbo
Automatic (S6)
Regular Gasoline
27 / 35 / 30
Sonic 5 Front-Wheel Drive
1.8 L, 4 cyl
Manual 5-spd
Regular Gasoline
26 / 35 / 29
Sonic 5 Front-Wheel Drive
1.8 L, 4 cyl
Automatic (S6)
Regular Gasoline
25 / 34 / 28
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