G Klasse engine screaming for help low oil pressure

That sounds rough. I had a similar issue with my G Klasse though it's a slightly older model. The oil pressure light came on, and there was definitely some extra engine noise. Have you checked the oil level? Also, what oil viscosity are you currently running? And is the oil pressure sensor working properly? These are easy things to check before assuming the worst.

Oil level is fine, I just did an oil change about 5000 km ago, using the recommended oil viscosity. How can I check the oil pressure sensor?

Okay, good to rule those out. Checking the oil pressure sensor can be tricky without the right tools. You'd ideally use a mechanical gauge to compare its reading against what the sensor reports. Given the mechanical noises you described, and the fact that the light is on even with good oil level and proper viscosity, it really does point towards a potential oil pump failure. If the pump isn't doing its job, it could starve the engine bearings of oil, which explains the noise. Honestly, at this point, I would stop driving it and get it to a workshop to avoid further damage.

Yep, you were right. Towed it to the shop, and it was indeed the oil pump failure. They are quoting me around 755€ for the repair. Seems reasonable. Thanks for the advice!