2010 Mercedes-Benz GLK-Class Problems: 2 Issues Every Owner Should Know

2010 model year · 930+ owner reports · Updated May 2026

According to Au7o's analysis of 930+ owner reports, the 2010 Mercedes-Benz GLK-Class has 2 documented known issues, with 1 rated critical. The most serious is Diesel Injector Leak and Black Death (OM651) ($400-$2,000 repair). The most commonly reported issue is Diesel Injector Leak and Black Death (OM651) with 550 owner reports. Across all issues, repair costs range from $400 to $2,000. DIY maintenance guides at au7o.io.

All 2 Known Issues

Community Reported

550 owners

On the 2010-2015 Mercedes-Benz GLK-Class 2.1L I4 Diesel OM651, the OM651 diesel injectors in the GLK develop a condition known as "Black Death" where the copper injector sealing washers fail, allowing combustion gases to escape around the injector. The escaping gases carbonize and create hard black tar deposits around the injector bore, eventually welding the injector in place and making removal extremely difficult.

This issue also affects: Dacia Sandero, Chevrolet Silverado 2500HD, Ford Transit

Common Symptoms

Black tar deposits around diesel injectors
Ticking noise from engine that changes with RPM
Diesel smell in engine bay
Rough idle
Slight loss of power

How to Fix

Replace the injector sealing washers and clean the injector bores of carbon deposits. If caught early, this is a relatively simple repair. Advanced cases require specialized injector extraction tools and potentially new injectors. Replace all four injector washers simultaneously to prevent repeat failures.

What Owners Are Using

Parts and tips from 550+ owners who fixed this issue

NoteInspect the injector area at every oil change. If you see any black deposits forming around the injectors, replace the copper washers immediately. Waiting turns a $200 repair into a $2,000 nightmare.

Typical repair cost:$400 - $2,000

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550+ owners have reported this issue

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Community Reported

High Confidence550 reportsLast reported by owners Sep 2025Reviewed Mar 2026

Community Reported

380 owners

On the 2010-2015 Mercedes-Benz GLK-Class, the front strut top mounts on the GLK-Class wear prematurely, producing a clunking or knocking noise over bumps and during low-speed turning. The rubber isolator within the mount hardens and cracks, transmitting road impacts directly into the body. This is especially noticeable on rough roads and at low speeds.

This issue also affects: Mercedes-Benz CLS-Class, Mercedes-Benz M-Class, Mercedes-Benz SLK/SLC

Common Symptoms

Clunking noise over bumps from front end
Knocking sound during slow-speed turns
Vibration through steering wheel on rough roads
Uneven front tire wear

How to Fix

Replace both front strut mounts along with the strut bearings. It is recommended to replace the complete front struts at the same time if they have more than 60,000 miles. Perform a wheel alignment after strut mount replacement.

What Owners Are Using

Parts and tips from 380+ owners who fixed this issue

UpgradeLemforder strut mounts are OEM quality at a lower price than Mercedes-branded parts. Direct fit for the GLK with no modifications needed. (Lemforder #35666)
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Typical repair cost:$400 - $1,000

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380+ owners have reported this issue

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Community Reported

High Confidence380 reportsLast reported by owners Jul 2025Reviewed Mar 2026

Frequently Asked Questions

What are the most common Mercedes-Benz GLK-Class problems?

According to Au7o's analysis of 930+ owner reports, the 2010-2010 Mercedes-Benz GLK-Class has 2 documented issues. The most frequently reported are: Diesel Injector Leak and Black Death (OM651), Front Suspension Strut Mount Noise and Wear. Of these, 1 is rated critical and should be addressed promptly.

Is the Mercedes-Benz GLK-Class reliable?

The 2010-2010 Mercedes-Benz GLK-Class has 2 known issues documented across 930+ owner reports. 1 issue is rated critical: Diesel Injector Leak and Black Death (OM651). Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common Mercedes-Benz GLK-Class problems?

Repair costs for known Mercedes-Benz GLK-Class issues range from $400 to $2,000, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Diesel Injector Leak and Black Death (OM651), typically costs $400-$2,000 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

What is the 2010-2015 Mercedes-Benz GLK-Class Diesel Injector Leak and Black Death (OM651)?

The OM651 diesel injectors in the GLK develop a condition known as "Black Death" where the copper injector sealing washers fail, allowing combustion gases to escape around the injector. The escaping gases carbonize and create hard black tar deposits around the injector bore, even… Repairs typically run $400-$2,000. Severity: high.

What is the 2010-2015 Mercedes-Benz GLK-Class Front Suspension Strut Mount Noise and Wear?

The front strut top mounts on the GLK-Class wear prematurely, producing a clunking or knocking noise over bumps and during low-speed turning. The rubber isolator within the mount hardens and cracks, transmitting road impacts directly into the body. This is especially noticeable o… Repairs typically run $400-$1,000. Severity: low.

2010 Mercedes-Benz GLK-Class Problems: 2 Issues Every Owner Should Know

All 2 Known Issues

2010-2015 Mercedes-Benz GLK-Class: Diesel Injector Leak and Black Death (OM651)#

Common Symptoms

How to Fix

What Owners Are Using

Research This Issue

2010-2015 Mercedes-Benz GLK-Class: Front Suspension Strut Mount Noise and Wear#

Common Symptoms

How to Fix

What Owners Are Using

Research This Issue

Other Mercedes-Benz Models

Frequently Asked Questions

What are the most common Mercedes-Benz GLK-Class problems?

Is the Mercedes-Benz GLK-Class reliable?

How much does it cost to fix common Mercedes-Benz GLK-Class problems?

What is the 2010-2015 Mercedes-Benz GLK-Class Diesel Injector Leak and Black Death (OM651)?

What is the 2010-2015 Mercedes-Benz GLK-Class Front Suspension Strut Mount Noise and Wear?