Mercedes-Benz A-Class Radiator: Specs, Fitment & Common Faults
On the A-Class, a water pump and thermostat housing failing together on related models has genuinely been quoted at around £550 — Mercedes-Benz UK offered a 50% goodwill discount specifically on the water pump.
Illustration for editorial purposes
Opens live listings in a new tab.
Mercedes-Benz A-Class Radiator: OEM Part Number
| Manual gearbox (older/entry variants, where fitted) | No dedicated transmission cooling circuit required |
|---|---|
| 7G-Tronic/9G-Tronic automatic, standard engines | A separate, standalone transmission oil cooler is fitted ahead of the main radiator and air conditioning condenser — confirmed as a genuinely distinct component from the radiator itself, not a tank integrated into it |
| AMG/higher-output engines | Larger-capacity cooling package overall, including a bigger dedicated transmission cooler to cope with the increased heat generated by the more powerful engine and harder-working transmission |
| 4MATIC (four-wheel drive) variants | The transfer case shares the same transmission fluid, adding an additional heat load compared to rear-wheel-drive variants |
Mercedes-Benz A-Class Radiator: The Part That Keeps Everything Else From Cooking
Nothing about this component is glamorous, but on the Mercedes-Benz A-Class, almost every serious engine failure that isn't wear-related traces back to a cooling system problem left unaddressed. Catching the early signs here is genuinely cheap insurance against a much bigger bill.
Mercedes-Benz A-Class Radiator: What It Does
The Mercedes-Benz A-Class's radiator transfers heat from the engine coolant to the surrounding air, keeping engine temperature within a safe operating range. On automatic versions, it often also cools transmission fluid through a separate internal circuit — one more reason the correct part number matters so much here.
Opens live listings in a new tab.
A Genuinely Alarming, Honest Real Account Worth Knowing — Mercedes-Benz A-Class Radiator
If a water pump and thermostat housing have both been found leaking at the same time, this is genuinely worth knowing: a water pump and thermostat housing failing together has been documented on genuinely young, low-mileage related models, with a combined repair cost of around £550 in one documented case. Mercedes-Benz UK offered a genuine 50% goodwill discount specifically on the water pump element, on the basis it had failed earlier than would reasonably be expected, worth directly asking for this kind of discount if facing a similar early failure.
It's also genuinely worth knowing that a slow water pump seal leak can drip coolant directly onto the spinning pulley behind it, which flings the coolant off, making a genuine leak surprisingly difficult to trace for some time.
Mercedes-Benz A-Class 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 Mercedes-Benz Radiator
The same part, covered across other Mercedes-Benz models.