When it is raining, water comes in at the front of the floor board on the drivers side and the passenger side. It starts way at the top by the gas and break pedals and runs down. It is quite a bit of
wind shield have any cracks or rust around the wind shield?
Have your windshield resealed.
It's your sunroof vent tubes located at the front of your sun roof on left and right sides. They could be clogged or like mine just out of place. I fixed mine but it's complicated to explain but I do have photos. It wasn't hard to do but took time. It's dangerous on the right pannenger side because it will drip down on the fuses inside that little panel on the right. Let me know if you need help and I will send you info and photos.
Looking for a Used M-Class in your area?
CarGurus has 5,252 nationwide M-Class listings starting at $2,500.
Search Mercedes-Benz M-Class Questions
Mercedes-Benz M-Class Experts