Air filters change every A and B service which is every 10k and if you live in the dusty area I would change is every 5-7k interval.
Trans filter check your manual and MB dealer recommendation for your model. I do a trans fluid drain and fill every 30-40k on all my Benz new or old, don't care if the dealer told me that the trans isn't need to service for life time of the car. It's all BS
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