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A-service, B-service and what your ASSYST counter actually means

Which service you're due for, what should be included, and which recommendations are an upsell.

Applies to · All Mercedes-Benz models

A versus B

A-service is the shorter one: oil and filter to the correct specification, the fluid and wear checks your schedule calls for, tyre pressure, and the service counter reset.

B-service is the longer one: everything in A plus the items due at that interval — typically the cabin filter, often the brake fluid, and a wider inspection.

The exact contents move by model year and market, so we confirm from your car's own service schedule before quoting rather than selling you a package.

Fixed versus flexible intervals

The long intervals on the dash assume long-life oil and mostly highway driving. City traffic, dust, short trips and cold weather all shorten that.

In Edmonton specifically: road salt, winter driving and repeated short cold runs are hard on oil. We lean toward shorter intervals than the counter asks for, and we'll explain why rather than just recommending it.

What we include as standard

Oil to the specification your engine requires (229.5 or 229.71 depending on engine), the correct filter, and the counter reset.

Brake fluid exchange when it's due, because moisture in brake fluid corrodes the module from the inside and it's cheap to prevent.

A written condition report with photos: pad and disc thickness, fluid conditions, suspension condition, tyre wear patterns. You keep the report whether you buy anything or not.

What's usually an upsell

"Engine flush" at every service. "Fuel system cleaning" every 10,000 km. Additive bundles added to a fresh oil change. Air filter changes every service rather than when they're loaded.

None of these are evil on their own — but if they're being recommended at every single visit, that's a business model, not a service schedule.

Questions owners ask about this

My counter says 18,000 km left. Should I really wait?
On highway miles with correct oil, you can. On short city trips through an Edmonton winter, we'd take half of that. Tell us how the car is actually used and we'll tell you which end of the range to sit on.
Does an independent service void my warranty?
Servicing by an independent shop does not by itself void a manufacturer warranty, provided the correct parts, fluids and specifications are used and documented. If your car is still under warranty we'll tell you which items should still go to the dealer and why, before you book.
Can you do the service and the inspection in one visit?
Yes, and normally we do — the condition report is part of the service. If something needs attention, you get the estimate before we touch it.