Ford Focus Mk3 Radiator: Specs, Fitment & Common Faults
The Mk3's 1.0 EcoBoost has a well-documented degas bottle cracking issue — serious enough to be referenced in a UK Parliament transport committee document.
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The 1.0 EcoBoost's Degas Bottle Has a Well-Documented Cracking Tendency
Across the 1.0 EcoBoost family generally (primarily 2012-2017 production), the plastic degas bottle (coolant reservoir) and its connecting hoses have a well-documented tendency to develop hairline cracks as the plastic ages and heat-cycles over years of use — serious enough that a UK Parliament transport committee document specifically references "failure of the degas pipe affecting 1.0L Fox engines" as a known issue Ford was asked to address. Watch for dropping coolant levels requiring more than one top-up between services, a sweet smell from the engine bay, or white smoke from the exhaust on starting — all worth investigating promptly rather than simply topping up and continuing to drive.
Ford Focus Mk3 Radiator: The Part That Keeps Everything Else From Cooking
Unglamorous as it is, the Ford Focus Mk3's cooling system sits behind nearly every serious engine failure that isn't just ordinary wear — and one that went unaddressed for too long. Noticing early warning signs here is a small cost against a potentially very large one.
OEM Part Number: CV6Z-8005-U
| Most petrol/diesel variants, 2013–2018 | Ford OEM: CV6Z-8005-U |
|---|---|
| 1.0 EcoBoost, 2015–2016 | Ford OEM: CV6Z-8005-W |
| Automatic transmission models (torque converter) | Includes an internal transmission fluid cooler as a separate circuit within the radiator tank — not present on manual-spec radiators; if this internal cooler fails, coolant and transmission fluid mix into a pink, milky fluid nicknamed the "strawberry milkshake of death" by owners and technicians, which can destroy the transmission if not caught quickly |
| Powershift (dual-clutch automatic) | Genuinely uses a separate standalone transmission oil cooler mounted ahead of the radiator and condenser, rather than an internal circuit built into the radiator itself — a different cooling architecture from the older-style automatic's integrated design |
Ford revised the Focus Mk3's radiator part number more than once across its production run, and automatic-transmission cars use a version with an additional internal cooler circuit that manual cars don't have. Confirm your transmission type and engine before ordering, since the wrong version will fit physically but won't cool the transmission fluid correctly.
Ford Focus Mk3 Radiator: What It Does
On the Ford Focus Mk3, engine coolant sheds its heat into the passing air via the radiator, which is what keeps engine temperature in a safe working range. On automatics, it frequently pulls double duty cooling the transmission fluid through its own internal circuit — a detail that makes getting the exact part number right especially important.
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Ford Focus Mk3 Radiator: Faults, DIY Difficulty & Aftermarket Advice
These are the same regardless of make or model — see our full Radiator Guide for the three common failure modes, confirming fitment against your VIN, and OEM vs aftermarket guidance.
More Ford Radiator
The same part, covered across other Ford models.