Before you buy a used Mercedes-Benz GLK (X204).
Taken only from Testigo's sourced sheets. Use it to question the seller and on the test drive: it does not confirm that any particular car is affected.

The essentials.
- 3 documented, sourced faults across its 2 engines.
- 1 of them depends on the equipment or the production date: ask what this car has.
- We have no official recalls on record for this model; ask anyway, with the chassis number (VIN).
- According to the data we have, all its engines have the same number of documented faults.
Typical faults by engine
The period and mileage are those mentioned by each sheet's sources. They are not a maintenance interval and do not predict that any particular car will fail.
All versions
Sheets the catalogue links to all 2 of its engines.
- 7G-Tronic conductor plateGearbox
- Period mentioned
- 2004 onwards (more failures in 2004–2008)
- Mileage mentioned
- The sheet does not mention a mileage.
Applies if: Only if fitted with 7G-Tronic. Confirm the gearbox type.
GLK 200 / 220 / 250 CDI (OM651)
Diesel
- Chain, injectors and coolant leaksTiming / injection
- Period mentioned
- 2008 onwards
- Mileage mentioned
- The sheet does not mention a mileage.
GLK 320 / 350 CDI (OM642)
Diesel
- Oil cooler and injector leaksOil leaks / injectors
- Period mentioned
- 2005 onwards
- Mileage mentioned
- The sheet does not mention a mileage.
Which engine has the fewest documented faults?
| Engine | Documented faults |
|---|---|
| GLK 200 / 220 / 250 CDI (OM651)Diesel | 21 with conditions |
| GLK 320 / 350 CDI (OM642)Diesel | 21 with conditions |
According to the data we have, all its engines have the same number of documented faults.
We only count the sourced sheets we have. An engine with fewer is not guaranteed to be more reliable: it may have been studied less or sold in smaller numbers.
Official recalls: ask before you pay
We have no official recalls on record for this model. Our list is not complete: ask anyway, with the chassis number.
- Ask the seller for the chassis number (VIN): it has 17 characters, appears in the car's documents and can usually also be seen at the base of the windscreen.
- Ask an official Mercedes-Benz dealer, or the brand's official website if it lets you check by chassis number, whether each recall has been done or is still outstanding for that VIN.
- Manufacturer recalls are normally carried out free of charge by the official service network. If one is outstanding, ask for it to be done before you close the sale.
On the test drive: what to look and listen for
Taken from each sheet's symptoms and checks. You can tick off what you have already looked at: it is saved only in this browser.
0 of 3 checked
Timing / injection
Look out for: Chain rattle on a cold start; on early units, loud injector knocking; coolant loss from the plastic coolant manifold or the EGR cooler.
Ask them to check: Listen to a cold start, check the dealer's injector campaign history and check the coolant level.
Oil leaks / injectors
Look out for: Oil pooling in the engine's V, burning oil smell, drips under the engine; or a hiss or chirp next to an injector with an exhaust smell.
Ask them to check: Visual inspection of the engine's V and the base of the injectors.
Gearbox
Look out for: Gearbox stuck in 2nd or 3rd (limp mode), harsh shifts, delay engaging D or R, gearbox warning often without an engine light; turning off and restarting clears it for a while.
Ask them to check: Diagnose with Xentry/STAR to see the sub-codes (a basic reader only shows P0700). Check for oil in the gearbox connector.
Sources
Every fact on this page comes from these Testigo sheets and their original sources. Sources are not checked in real time.
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