Mercedes-Benz CLA Radiator: Specs, Fitment & Common Faults
A genuinely honest finding: a recurring coolant leak, even after a genuine water pump replacement, was suspected to be caused by an earlier repair using the wrong type of clamp on plastic coolant system parts.
Illustration for editorial purposes
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Mercedes-Benz CLA 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 CLA Radiator: The Part That Keeps Everything Else From Cooking
This isn't a part anyone gets excited about, but on the Mercedes-Benz CLA, overlooked cooling problems are responsible for most serious engine failures that aren't simple wear-and-tear. Catching the early symptoms is about the cheapest insurance available against a major bill later.
Mercedes-Benz CLA Radiator: What It Does
Keeping the Mercedes-Benz CLA's engine temperature within safe limits comes down to the radiator's job of transferring heat from the coolant into the surrounding air. Automatic-gearbox versions often build in a second circuit for transmission fluid cooling too, which is exactly why fitting the wrong part number can cause two problems, not one.
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A Genuinely Honest, Real Finding Worth Knowing — Mercedes-Benz CLA Radiator
If a coolant leak has recurred even after a water pump has genuinely already been replaced, this is genuinely worth knowing: one documented case suspected the underlying cause was an earlier, non-main-dealer garage having replaced the original Mercedes-specific hose clamps with generic aftermarket ones during a previous repair, since fitting the wrong type of clamp onto plastic coolant system components has been directly described as a common cause of recurring failure. Worth asking specifically what clamps were used if a coolant-related repair has previously been carried out by an independent garage rather than a main dealer, particularly if a leak keeps returning despite the water pump itself already having been replaced.
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 CLA 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.