Hi all,

I'm reading through posts educating myself on the GLK, but as I continue reading, a few questions came to mind for which I've seen no reference to.

My questions are for the diesel GLK250 folks. Considering all warranties from MB are over by now, what does it run to fix the typical diesel repairs that were once covered under the Mercedes class action lawsuit? Also, are these repairs a long-term fix for the problem (not to be confused with permanent fix)? Or are the issues recurring frequently? Just trying to see what to expect.

Thanks for your input as I continue to learn about these rides.

 

Welcome!

It all depends on what exactly goes wrong, and that's hard to guess at since it could be literally anything. Things like the AdBlue tank heater and tank level sensor are known to fail, but there are repair kits for it. The original heaters have failed on many cars and have been repaired by dealerships as well as Indy shops or DIYers. There have been some reports of the SCR injectors clogging here and there, which means removal and cleaning or replacing if not serviceable.

I'd say by far the most expensive component is the DPF itself, and even though these have mostly been replaced as part of the recall work, the sensors around them can go wonky without warning. And there are many sensors in the system... Some sensors have double duty, such as pressure and temperature, but only one of the two functions may be affected making it difficult to know which sensor is acting up. Add to that the fact that most new sensors need to be "learned" to the car in order for them to work properly and it means you'll also need a dealer-level quality scan tool to make those adaptations to the ECU. Otherwise, if sensors are acting up, simply replacing them won't solve the problem and you'll still be left with a check engine light, along with the inability of the DPF to undergo regeneration, and that will put you into "limp home" mode.

I would advise that if you're not familiar with modern diesels and their requirements, probably best to stick with gassers. What you save in fuel costs on a diesel you'll definitely spend on increased maintenance costs and possible repairs. Not to mention that most Bluetecs are now at least 10 years old and will need more repairs, such as suspension refresh and other items. I tell people all the time, "there's nothing more expensive than a cheap Mercedes."

 

Our opinion only. Been wrenching on cars and motorcycles for over 40 years, so could tackle a diesel.

But, we didn't want all the extra hassle associated. Which is why we chose the GLK350 Base (2014 gasser), now with 93,000 miles (no major issues). Previously, had an E320 with 330,000 US miles, no major issues.

 

I'm about to run out of kilometers in the next couple of months in the extended warranty. Here is what the documentation i have says

The Extended Modification Warranty period shall be the greater of: (i) 10 years from the date of initial sale or 193,000 kilometers on the odometer, whichever occurs first; or (ii) 4 years or 77,250 kilometers from the date of installation of the Field Measure, whichever occurs first.

• Diesel Oxidation Catalyst (DOC)
• Diesel Particulate Filter (DPF)
• Selective Catalytic Reduction (SCR) Catalyst
• Diesel Exhaust Fluid (DEF) Injector
• Diesel Exhaust Fluid (DEF) Injector Controller
• Diesel Exhaust Fluid (DEF) Supply Module
• Diesel Exhaust Fluid (DEF) Pump
• Temperature Sensor Unit (DEF Temperature Sensor)
• Exhaust Temperature Sensor
• Particulate Matter (PM) Sensor
• Lambda Sensor (Emission Modification Categories 1-5 ONLY)
• NOx Sensors
• Fuel Injectors
• Air Intake Throttle
• Exhaust Gas Recirculation (EGR) Valve
• Exhaust Gas Recirculation (EGR) Duct
• Exhaust Gas Recirculation (EGR) Cooler (including bypass control)
• Exhaust Gas Recirculation (EGR) Temperature Sensor
• Intake Manifold/Charge Air Distributor
• Turbocharger (including VGT Actuator)
• Engine Control Unit (ECU) Hardware (where replaced as part of the Approved Emission Modification)
• Transmission Control Unit (TCU) Hardware (where replaced as part of the Approved Emission Modification)
• Hydraulic Control Unit (HCU) Hardware (where replaced as part of the Approved Emission Modification)
• Cylinder Head Assembly Components (camshafts, valves, springs, valve spring keepers, valve seats, cam bearing caps, and manifold studs)
• Engine Timing Chain
• Intake Manifold Pressure Sensor
• Instrument Cluster Hardware (where replaced as part of the Approved Emission Modification)
• Coolant Thermostat (where replaced as part of the Approved Emission Modification)
• Crankcase Ventilation Valve (including line and heating element)

 

Thanks for the input, Gents. I don't have a diesel yet, but I've been flirting with the idea for quite some time. The Bluetec GLK still seems a "safer" entry vehicle than a V10 VW Touareg (another diesel I'd love to have). Still reading through the threads gathering info.

What's the recommended dealer-level diagnostic software for Mercs nowadays? Is it still STAR?

This is a longer list than I had come across before. I take it this list is what is covered under warranty if a problem was to arise. Not to be confused with the list of items changed as part of the "recall", correct? I think only a handful of items were changed under the recall, and on top of that the extended warranty kicked in and covered all the items listed here.

 

Correct, the list is what’s covered under the terms of the AEM warranty, not what was replaced. Most folks got new DPFs, perhaps NOx sensors, TCU updates and ECU updated software.

 

Well, not quite yet; have until April '25 under the extended warranty. Coming fast, though -