Summer 2026: What to Check on Your GM Vehicle

Summer in Texas is a heat problem, not a driving problem. Heat is what kills batteries, coolant, hoses and wiper blades. The failures that strand people in July were visible in May if anybody had looked.

Cooling System

The usual tell is a heater that blows cool at idle and warm at speed. GM’s long-life coolant is generally rated for 5 years or 150,000 miles on the first fill and 5 years or 100,000 miles after that. Hoses and the surge tank should be inspected annually once past 80,000 miles.

Parts in this group: radiators, water pumps, thermostats, coolant hoses, cooling fans. Engine, tow package and rear-A/C content all change the radiator and hose part numbers. Have the VIN ready.

Electrical and Charging

The usual tell is 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.

Parts in this group: batteries, battery cables, alternators, starters, body control modules. Vehicles with stop-start often use two batteries. Confirm which one you are replacing before ordering.

Heating and Air Conditioning

The usual tell is a musty smell for the first thirty seconds after startup. 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.

Parts in this group: cabin air filters, blower motors, blower motor resistors, A/C compressors, condensers. Rear climate content, heated and cooled seats, and tri-zone systems all change the parts list.

Filters and Fluids

The usual tell is a slight hesitation on hard acceleration with a dirty air 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.

Parts in this group: oil filters, air filters, cabin air filters, fuel filters, transmission filters. Engine size and emissions equipment change the filter, and diesel filter kits in particular are not interchangeable across model years.

If You Only Do One Thing

Change the cabin air filter. It is the cheapest item here and the one almost nobody has touched.

If you are not sure which version fits your build, send us the VIN and we will confirm before anything ships. Shop our Chevrolet OEM parts catalog or search for Suburban parts.