This is a video on how to easily change the cabin air filter system on a Mercedes Benz GLS550 (X166). No need to pay the shop a TON of $$ to have a technician do this. It's a simple do-it-yourself job that will take you 10 minutes, at most, even on your 1st try. This vid is a bit longer than that to show the details and give an acceptable explanation on how to get the job done.

To my recollection, the procedure was very similar when doing the same job on our old 2015 MB GL550. the GL/GLS450 should be similar as well, as these are all X166 from model years 2012 through 2019, even after the January 2016 facelift/name change from GL to GLS.

I may profit from the links below. not really sure how the amazon affiliate thing works yet. but i just signed up for it on 9-Jan-24

Links for the parts I used:

ATTENTION - the links below are my amazon affiliate links. As an Amazon Associate, I earn from qualifying purchases.

Exterior Filter / the larger one
FRAM Fresh Breeze Cabin Air Filter with Arm & Hammer Baking Soda, CF11719
https://amzn.to/3vvFrnx


Interior Filters / 2 pack of the smaller ones
https://amzn.to/47pmGPW