I have a 06 E class CDI with 250K on it and love the car. Never an issue and just keeps humming along.
Are the newer diesels as bullet proof as my CDI with all the ad blue stuff? Or just go gas? My wife would like a GLE and not sure if I search out a diesel variant.
Thanks for the guidance.

You and the wife really need to go for a test drive before deciding. Personally I would find a pre-2007 model as that was before they implemented all the pollution control junk that make the newer diesel not as reliable. Note that the GLE 2016 uses the 2.0L engine and not the V6 3.0L engine(OM642).

The OM642 engine is a reliable engine, just all pollution control crap makes it not reliable: DPF requires the need to run 229.51/229.52 oil instead of the older 228.3. The 228.3 lubricates better and keeps the timing chain from wearing out as fast. The 229.51/229.52 are low saps vs 228.3 is medium saps and the low saps is needed to protect contamination of the DPF and CC. OM642 also has swirl flaps/swirl flap motors that are clogged by EGR deposits.

The following may or may not apply to the 2.0L diesel, but common on the OM642:
NOX Sensors need replacing unless you can live with the check engine light. DEF fluid need refilling and there have been issues with the DEF heater failing and this requires dropping the DEF tank to replace the heater.

Pretty much everything above applies to other manufactures in some respect or other. I previously owned a 2013 VW Touareg TDI and 2012 VW Jetta TDI. Both required low saps oil, required refilling DEF. In the case of the Touareg, I had to drop the DEF tank to replace DEF heater. NOX sensors on the Touareg kicked the CEL a few times, but I found if I took it for a nice run on the highway it would clear the CEL, however not so lucky with the ML 350.

Unless you are a hardcore diesel fan and/or require towing capabilities provided by the diesel, or do plenty of highway driving, ie 20,000 miles annually, it's just not worth getting another diesel. I personally love diesels and that is why I bought the ML 350 Bluetec. I am considering the idea of DPF delete, EGR Delete, etc...to extend the life of my current ML 350.

Thanks...kind of what I expected. My wife drives a 2015 Passat TDI that get 50 mpg but she wants to sit higher and the VW seats are not very comfortable. Need DEF fluid every 10K or so. The TDI has been rock solid and we have 85K on it now. She has a Jetta TDI before that with 150K that VW bought back due to emissions scandal....sweet deal for us. I had a GL320 also but was not as reliable as my 06.

Agree with Etienne.

I drove a 2010 Touareg 238k miles and had every diesel-related failure that exists on those vehicles. VAG did the right thing and bought the car from me, for a fair price.

M-B is not standing behind their defective product, so the common recommendation on this site is to strongly avoid the Bluetec vehicles generally later than 2007 or 2008.

The CDI pre-2007 vehicles are more reliable but are approaching 15 years old now, and nothing lasts forever.

I bought an 2015 E250 and put close to 90K miles on it so far. I liked it so much I bought a GLE 300d just recently for my wife. Same 2.1L engine and transmission. I strongly recommend you drive the diesel. It's an absolutely wonderful drivetrain for the GLE. It's pulls strong and the SUV is just effortless on the highway. We just drove to South Florida on a single fuel stop.

The diesel additive is readily available and can be added in about as much time and effort as windshield wiper fluid. Really not a consideration. The tank in the GLE is large enough for 20 or 25K miles, but I don't fill it all the way up.

No issues for me so far in 5 years and 90K miles.

BTW - I'm in NJ and I use Mercedes Benz of Morristown, their service department has been great for oil changes, etc.

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