How reliable has been your 2017-2019 GLS 450
I am on fence due to reliability.
MB is not as reliable as Honda or Toyota. But in the MB world, the 450 engine is about as good as it gets.
Last edited by ruturaj; Jun 12, 2024 at 12:27 PM.
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Engine is pretty bulletproof. Check now and then for cam sensor and cam magnet oil leaks in the wire harness connectors. Widespread issue on M274, M276, M278 and M157 engines.
Suspension, steering, brakes and body are solid. Entertainment and electronics don't have recurring issues. Keep an eye on sunroof drains, taillamp gaskets and rear liftgate gasket to avoid water intrusion and collateral electronic damage. Water intrusion on SUVs is a general MB issue across model years.
Change spark plugs every 40k or so miles. Change ignition coils with every other plug change.
Change all axle and transfer case oils before 75k miles.
Last edited by chassis; Jun 12, 2024 at 07:28 PM.
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Engine is pretty bulletproof. Check now and then for cam sensor and cam magnet oil leaks in the wire harness connectors. Widespread issue on M274, M276, M278 and M157 engines.
Suspension, steering, brakes and body are solid. Entertainment and electronics don't have recurring issues. Keep an eye on sunroof drains, taillamp gaskets and rear liftgate gasket to avoid water intrusion and collateral electronic damage. Water intrusion on SUVs is a general MB issue across model years.
Change spark plugs every 40k or so miles. Change ignition coils with every other plug change.
Change all axle and transfer case oils before 75k miles.
Would follow the rest as well. Suspension seems to need frequent replacement/repairs as well, are those possible to DIY?
Edit: seems like transmission fluid change isn't a DIY option but still not bad to pay once during ownership
https://mbworld.org/forums/gls-class...hange-diy.html
Last edited by ruturaj; Jun 13, 2024 at 03:09 PM.
Suspension air strut replacement seems straightforward, reading posts on this site.
Brakes are easy, if you have some prior DIY experience.
Saw another thread with Arnott shocks as suggested aftermarket replacement. Pricing is pretty good on them too.
Yes, I have replaced brakes multiple times on different vehicles. So not an issue there.
Last edited by chassis; Jun 17, 2024 at 09:41 PM.
Service $577.50
Oil Sump 164.00
10 screws 20.00
Fluid 292.00
Screw plug 8.00
Overflow pipe 11.00
Dealer in Raleigh, NC









3/1/20 (10k mi) - oil/filter
2/24/21 (18k mi)- oil/filter, cabin filter, brake flush
Warranty - cracked wood trim on driver's door card
11/16/21 (28k mi) - front discs/pads, oil/filter
6/29/22 (38k mi) - oil/filter
2/4/23 (45k mi) - wipers
Warranty - driver's knee airbag
4/19/23 (47k mi) - rear pads, new tires
6/4/23 (49k mi) - oil/filter
8/20/23 (52k mi) - brake flush
4/15/24 (55k mi) - trans filter/fluid, oil/filter

As a side note, for those in wintery/slippery climes, I used to run Blizzaks in the winter but grew weary of the biannual tire/wheel swap ritual and decided to try the Crossclimate 2's year round. I can confidently say there is no need to run a dedicated winter tire any longer. The CC2's work great in deep snow/ice/slush in hilly/mountainous terrain (we're @8k ft in the Rockies). As a huge benefit, the CC2's are super quiet and are rated to last 60k miles!






