Bought our 2017 GLC-300 Coupe 1 year and 5 months ago. We put 30K miles on the vehicle before it started to rev high on my wife while driving at 65mph on the freeway. She pulled to the side and turned the engine off and sat for about 30 mins. Things seemed to subside but we needed to get it checked out anyway.

We brought it to Mercedes-Benz Fletcher Jones Las Vegas. We spoke to Curtis Terry, Service Director. He was well aware of the possible issue with our vehicle and even said it maybe the piston ring, or the piston typically in the piston 1 or piston 2 area. He went on to show me where he already had an engine disassembled for the exact same thing and where if our engine was scorched by the fragmented piston ring or piston, that we would need a whole complete engine. WTF?

It needed a whole engine, and he got Mercedes-Benz to pay for the whole new engine, but we had to pay for the labor? WTF? He explained to us why he felt this was a manufacturer defect from MBZ because of the laws to increase fuel economy and in MBZ's attempt to increase mileage, MBZ used material cheaper to manufacturer and made smaller engines. He mentioned this issue occurred in 2015-2017 GLC 300 engines and some C class engines with the 4 cylinder. He also mentioned he has seen the same thing in engines with only 20K miles on it.

I'm not satisfied we had to pay anything at all due to the manufacturer defect in the engine. Curtis went on to say that MBZ stance is that U.S. gas production has alcohol in it and it wears down the piston rings to chip and break apart.

How many more GLC 300 engine issues with piston 1 or piston 2 has to occur before a recall has to happen? MBZ, the Service Directors and many mechanics in town are aware of the issue. The only thing I haven't heard about is someone dying from this issue. I hope it doesn't get to that before NTSB steps in or a class action suit is filed. Who's in if there is one?