Coolant flush for Somersett drivers: Mae Anne Avenue, 10 minutes

When was the coolant in your car last changed? Most Somersett owners we ask cannot say, and that is normal, because long-life coolant goes years between services. The trouble is that those years pass quietly in a neighborhood that sits on the hillside above the Truckee River, where every trip home ends in a climb and every January morning starts cold. Census does not publish Somersett on its own, so we lean on the 89523 ZIP it belongs to: 1.91 vehicles per household and a 21.9 minute average commute (ACS 5-year 2024).

Down the hill and back up

Somersett Parkway brings you down to the valley floor; from there, Mae Anne Avenue runs south toward McCarran and the bay is on the left before you reach it. The trip down is easy on an engine. The trip home is not: the climb back into the neighborhood with the A/C running on a July afternoon is the moment a tired radiator cap or weak coolant shows itself on the temperature gauge.

The Reno-Tahoe airport station, a few miles east and lower, averages 65 days a year at 90 F or hotter and about six at 100 F or hotter (NOAA 1991-2020 normals). Higher on the hill the air is a little cooler but also thinner, and thin air carries heat away from a radiator less efficiently.

The test comes before the flush

A coolant visit at Mae Anne starts with a sample on a refractometer, which reads the freeze point in seconds. The technician also looks at the fluid itself. Clear and the right color is good news. Rusty, cloudy or oily is not, and oil in the coolant is a sign for a repair shop, not for us.

When the flush is the right call, we drain the radiator and the block where the design permits, refill with the coolant your manufacturer specifies at the correct mix, bleed out trapped air so the heater blows warm and the gauge reads true, and check the cap, hoses and reservoir. Old coolant goes to recycling. Anything over fifty dollars is quoted in writing first under Nevada's NRS 487.6875, and you decide.

Which coolant your car takes

AAA groups coolant into IAT, the old green kind good for about two years or 24,000 miles; OAT, common on GM vehicles at about five years or 50,000 miles; and HOAT, common in Ford and Chrysler vehicles at about five years or 50,000, with some makers going to ten years or 150,000. AAA's own advice is to ignore the color and follow the owner's manual, and the manual is what we follow too.

Winter on the hillside

Reno averages about 122 nights a year at or below freezing and 25 at 20 F or colder (NOAA). Cars parked on a Somersett driveway see those nights first. Coolant that has been diluted with water over a few top-offs might freeze in the overflow tank or, worse, in the block. A freeze test in October is cheap insurance before the first hard cold, and it takes the technician a minute during an oil change.