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Reliability report · 2018 Mazda CX-5 · Updated July 2026 · ~$2,200/yr fuel · what it costs to keep →

The year cylinder deactivation arrived — and with it the cracked-cylinder-head pattern the non-turbo engine never got covered for.

On paper the 2018 is quiet: 113 complaints. But the recent filings cluster hard on one thing — a cracked cylinder head on the 2.5L SkyActiv-G naturally aspirated engine, the version that gained cylinder deactivation for 2018. The crack leaks oil onto the hot exhaust manifold, a genuine fire risk, and it tends to appear between roughly 50,000 and 120,000 miles.

The catch that makes this a Squawking year: Mazda handled the crack differently by engine. The turbo 2.5T got a warranty extension for its version (a coolant leak); the non-turbo 2.5 got only a technical service bulletin and a revised head design — no warranty extension — so out-of-warranty repairs land on the owner, with one head-gasket job quoted around $2,500. Add three recalls (side-curtain airbags, a PCM stall-software fix, and the low-pressure fuel pump) and this is a year to inspect the engine specifically before buying.

Evidence: 113 NHTSA complaints · 3 recall campaigns · 7 mechanic & forum sources

Canary status

Squawking

What that means: 113 federal complaints — a low count, but the recent filings are dominated by one expensive, out-of-warranty pattern: a cracked cylinder head on the 2.5L non-turbo engine that leaks oil onto the exhaust, a fire risk Mazda addressed with a bulletin and a revised head rather than a warranty extension. Three recalls sit on top. Avoidable with the right checks, costly without them.

CalmChirpingSquawkingFainted

113

Federal complaints

3

Recalls

Federal crash tests

5-star scale
Overall
Frontal crash
Side crash
Rollover

Tested variant: 2018 Mazda CX-5 SUV FWD Later Release (NHTSA VehicleId 12814)

Source: NHTSA New Car Assessment Program (NCAP)

Known issues

Ranked by the cost of ignoring them. Every claim carries its source.

Cracked cylinder head — oil leak onto exhaust (2.5L non-turbo, no warranty extension)

major
  • 2.5L SkyActiv-G (non-turbo, cylinder deactivation)

The defining 2018 pattern. On the 2.5L naturally aspirated SkyActiv-G — the engine that gained cylinder deactivation for 2018 (VIN 8th digit M) — the cylinder head can crack behind the exhaust manifold, leaking oil onto the hot exhaust with a burning smell and fire potential. Mazda acknowledged it but, for the non-turbo, issued only a TSB — a Technical Service Bulletin, the fix instructions automakers send dealers — plus a revised head design, with no warranty extension. Out of warranty, owners pay: one head-gasket repair was quoted about $2,500, and several report the leak recurring. Inspect the engine for oil residue near the exhaust and a burning-oil smell, and treat any leak history seriously.

This is a 2.5L SkyActiv-G (non-turbo, cylinder deactivation) problem. The 2.5L SkyActiv-G Turbo (2.5T) doesn’t share it.

Which engine is in the one you found? →

Head/gasket repair (one owner quote)

~$2,500

Cracked-head engine job (owner reports)

several thousand

Sources: NHTSA complaint database, 2018 Mazda CX-5 · Independent mechanic and owner channel transcripts (CX-5 second generation)

Side curtain airbag recallmoderate

Recall 18V426 (Mazda code 2718F) covers 2018 CX-5s whose side curtain airbags may not unfold properly in a side impact or rollover — a noncompliance with the federal ejection-mitigation standard. The remedy is a free curtain-airbag replacement. Verify it shows completed by VIN.

Sources: NHTSA recalls + manufacturer communications (campaign documents, CSP/SSP windows)

$0

Recall remedy

PCM stall-software and low-pressure fuel-pump recallsmoderate

Two more recalls touch the 2018. 19V497 (Mazda 3719F) reprograms the powertrain control module — the PCM, the engine's computer — after a software error that can stall the engine (2018–2019 CX-5). 21V875 (Mazda 5321K) replaces a Denso low-pressure fuel pump whose impeller can crack and cause a stall (CX-5 scope confirmed as 2018–2019). Both are free; confirm each is completed and ask whether the earlier CSP12 fuel-pump extension was ever used.

Sources: NHTSA recalls + manufacturer communications (campaign documents, CSP/SSP windows)

$0

Recall remedies

Thermostat P0126 warranty extension (SSPD8)minor

The 2018 falls in Mazda's SSPD8, a Special Service Program (a warranty extension) for a check-engine light with code P0126:00 — a fail-safe thermostat/coolant control valve stuck open, causing slow warm-up, a fluctuating temperature gauge, and weak heat at idle. Coverage was extended to 15 years or 150,000 miles. It's a cheap, covered fix if the code appears; confirm SSPD8 is noted and test that the engine reaches normal operating temperature.

Sources: NHTSA recalls + manufacturer communications (campaign documents, CSP/SSP windows)

The 2018 introduced cylinder deactivation on the 2.5 — and it's the year the cracked-head oil leak starts showing up, on an engine Mazda chose not to extend coverage for.
7 mechanic & owner sources

Open recalls

Free fixes at any Mazda dealer. Run the VIN — “completed” isn’t always completed.

  1. 18V426Side curtain airbags may not unfold properly in a side impact or rollover (FMVSS 226 noncompliance), 2018 CX-5. Free curtain-airbag replacement. Mazda code 2718F.open
  2. 19V497PCM software error may cause the engine to stall (2018–2019 CX-5, Mazda6, 2019 Mazda3). Free PCM reprogram. Mazda code 3719F.open
  3. 21V875Denso low-pressure fuel-pump impeller may crack and deform, causing pump failure and stall (CX-5 scope 2018–2019, among multiple Mazda models). Free fuel-pump replacement; letters July 2022. Mazda code 5321K.open

What it costs to keep

The purchase price is what you negotiate. These are the numbers you live with afterward — each one sourced, none of them blended into a fake total.

The ownership picture — 2018 CX-5

Three sourced numbers. No fake total.

Fuel

28 MPG combined (25 city / 31 highway) for the FWD, 2.5L on the EPA federal fuel-economy test.

Source: FuelEconomy.gov (EPA) — EPA’s federal fuel-economy test, recomputed with current gas prices. EPA record 39777 (CX-5 2WD).
Other builds EPA lists: 4WD, 2.5L 26 MPG · Diesel 4WD, 2.2L turbo 28 MPG · Diesel FWD, 2.2L turbo 29 MPG.

$2,200/yr

at $4.15/gal · 15,000 mi/yr · 55/45 city/hwy · pulled Jul 12, 2026

Theft

Stolen about 49% less often than the average vehicle. One less thing to price into coverage.

Source: HLDI — the insurance industry’s loss-data institute HLDI whole vehicle theft losses, 2016–18 models, published May 2019 (report WT-18). 100 = the all-vehicle average. Series read: Mazda CX-5 4dr 4WD.
Other series: Mazda CX-5 4dr 52, where 100 = average.

51 vs 100

49% below average

Repair risk

What this specific year is known to need. Pulled from the issues above — the repairs owners actually report, at the costs they report them. Averages from other sites blend every year together; these are this year’s own numbers.

Source: this report — 01 Known issues.

Head/gasket repair (one owner quote)~$2,500
Cracked-head engine job (owner reports)several thousand
Recall remedy$0
Recall remedies$0
Why there’s no single “cost to own” number: sites that promise one are guessing at your insurance quote, your annual miles, and your luck. These are the numbers we can actually source — and each one carries its receipt.

Shopping this year?

Get the printable pre-purchase checklist and an alert if this year’s recall sheet changes.

Have a specific one in your sights?

The VIN is on the listing. We’ll check this exact car — build, open recalls, and whether the “completed” repairs stayed fixed.

Before you buy

Print this
  1. 01Inspect the engine for oil residue near the exhaust manifold and a burning-oil smell — the cracked-cylinder-head leak on the 2.5 non-turbo is the year's expensive, uncovered risk.
  2. 02Ask directly whether the cylinder head was ever replaced (revised design) and get any engine-repair records.
  3. 03Run the VIN against 18V426 (curtain airbags), 19V497 (PCM stall), and 21V875 (fuel pump) and confirm each is completed.
  4. 04Confirm the P0126 thermostat program SSPD8 (15yr/150k extension) is noted; verify the engine warms to normal temperature.
  5. 05Ask whether the CSP12 low-pressure fuel-pump warranty extension was ever used.
  6. 06Favor a turbo 2.5T example only if you specifically want the turbo — its cracked-head version at least carries a coolant-leak warranty extension the non-turbo lacks.

Own one already?

The canary watches your VIN — new recalls and the mileage where known issues start.

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vincanary.com/mazda/cx-5/2018