Dear members

I will pick up my 2008 3.0 X5 next week. I live in the North East and with all the snow and salt in the winter I had to replace every 3-4 years the muffler or some part of the exhaust system in my previous vehicles. Also the engine compartment gets extremly rusty by 5 years.

This is my first BMW and i want to pamper it from the begining.

What do you spray under the car to protect it from rust?. Do you use the same thing in the engine?. Someone mention WD-40, will that protect from rust?.

Thank you so much for your time. Your input is appreciated.