Reliability report · 2018 Mazda CX-5 · Updated July 2026
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.
This status assumes the riskiest common powertrain — see the CX-5 engine guide.
113
Federal complaints
3
Recalls
several thousand
Cracked-head engine job (owner reports)
~$2,500
Head/gasket repair (one owner quote)
Ranked by the cost of ignoring them. Every claim carries its source.
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.
What to check
Pink and cleanServiced. Proceed.
Dark brownDamage underway.
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)
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
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
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.
Free fixes at any Mazda dealer. Run the VIN — “completed” isn’t always completed.