Presidents Day Towing Prep for Your 2020-2025 GMC Sierra 3500HD

Getting trailer wiring and brake controllers right before spring. Applied to a 2020-2025 Sierra 3500HD, here is what that looks like.

Exhaust and Emissions

Watch for a diesel that regenerates far more often than it used to. Not scheduled. Converters are warranted separately under federal emissions rules, so check coverage before you buy.

Electrical and Charging

Watch for a battery that tests fine at the counter but fails after sitting three days. Batteries in Texas heat routinely give up between three and five years. Test annually after year three, before the first cold snap.

Interior

Watch for a console lid hinge that has cracked at the pivot. Not scheduled. Replace on wear.

Heating and Air Conditioning

Watch for air that only blows on the highest fan setting. 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.

The Short Version

Catalytic converters: Emissions equipment varies by state of original sale on some model years.
Batteries: Vehicles with stop-start often use two batteries. Confirm which one you are replacing before ordering.
Floor liners: Interior color code matters as much as the model year. It is on the SPID label in the glove box or console.
Cabin air filters: Rear climate content, heated and cooled seats, and tri-zone systems all change the parts list.

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.