Spring Break Road Trip Prep: GMC Sierra 3500HD Edition

The checks worth doing before a long haul with a loaded truck. Applied to a 2020-2023 Sierra 3500HD, here is what that looks like.

Filters and Fluids

Watch for a diesel that derates or throws a fuel pressure code on a neglected filter. Follow the oil life monitor rather than a fixed mileage. Engine air filter every 30,000 to 45,000 miles. Transmission service intervals vary widely by transmission and by whether you tow.

Brakes

Watch for a pedal that sits lower than it used to, or sinks slowly at a stoplight. Inspect at every tire rotation. Most GM trucks and SUVs go 30,000 to 60,000 miles on front pads depending on how they are used, and towing cuts that hard.

Heating and Air Conditioning

Watch for a clicking or ticking behind the dash when you change temperature. Cabin air filter every 12,000 to 15,000 miles, or annually. In North Texas with construction dust and cedar season, annually is the honest number.

Exhaust and Emissions

Watch for a P0420 or P0430 efficiency code. Not scheduled. Converters are warranted separately under federal emissions rules, so check coverage before you buy.

The Short Version

Oil filters: Engine size and emissions equipment change the filter, and diesel filter kits in particular are not interchangeable across model years.
Brake pads: Front and rear pads are almost never the same part, and heavy duty, tow and performance brake packages use different calipers and rotors than the base vehicle.
Cabin air filters: Rear climate content, heated and cooled seats, and tri-zone systems all change the parts list.
Catalytic converters: Emissions equipment varies by state of original sale on some model years.

We stock genuine GM parts for every nameplate on this list and ship nationwide from Dallas. Start at our GMC OEM parts catalog, or search for Sierra 3500HD parts if you already know what you need.