1. Coolant System
Keeping cool is paramount, not just for ourselves but also for our cars. In addition to checking the level of coolant fluid in your car, go the extra mile and inspect the state of the hoses and the coolant reservoir. Keep an eye out for leaks, especially at joints and connection points, such as where a hose connects to the engine block. Also, squeeze the hoses (when the engine is cool) every once in a while to make sure they feel firm and not excessively squishy or soft.
2. Engine Belts
There is usually a serpentine belt that runs between the alternator, the fan and several other components. It can deteriorate, become loose, start to squeal, and sometimes just break for no apparent reason. It needs to be in good condition and at the right amount of tension. If you see cracks in the belt or small pieces missing, it's time to replace the belt.
3. Wipers
Yes, it's summer, but it's probably going to rain at some point. Worn wipers create nasty streaks across the windshield and can affect your vision while driving. Replacing them doesn't cost much, but it can be a fiddly operation. If you're in the habit of taking your car in for oil changes, ask them about the wipers, too. Sometimes a dealership will sell you the wipers and install them for free.
4. Other Essential Fluids
Check oil, brake, power-steering and windshield-washer fluids regularly. These liquids never stop being used and consumed. Speaking of brake fluid, how do the brakes on your car feel in general? Are they lacking in bite? Feeling a bit spongy? If so, new pads and a system bleed might be required. This is the kind of maintenance you should have your mechanic or dealership take care of.
5. Air-Conditioning System
Air-conditioning is a summer essential. If the system hasn't been working properly but wasn't really a pressing issue over the winter, now's the time to get serious. If it's an older system, then leaking Freon into the atmosphere is not good. There are plenty of leak-sealing products and refrigerant rechargers available from hobbyist stores and even places like Walmart. Remember, if there's not enough refrigerant in the system, you have a leak. Have a qualified mechanic fix the leak before paying to have the air-conditioning system recharged.
6. Air Filter
The winter's decomposing leaves may be clogging up drainage points, windshield-washer nozzles or your car's air filter. Now might be a good time to buy a new one or take the current one out and give it a cleaning. Many modern cars also have pollen filters or cabin filtration systems, so take a look at those, too. Sometimes these cabin filters are easy to change yourself. Like everything else mentioned here: When in doubt, consult a qualified technician.
7. Tires
Tires really need to be checked regularly all year round. Pressures must be correct (consult the manual because sometimes that information is on the inside of the fuel door or the door jamb for the driver's door), treads should be free of stones, stray nails and the like, and all four should be in good condition. Good condition means no cracks, no uneven wear (this might be caused by a suspension problem) and plenty of tread depth. Since summer is a time for road trips, it wouldn't be a bad idea to have a can of Fix-A-Flat that could at least get you to a shady spot where you could change the wheel more comfortably. The spare obviously needs to be usable, too.
8. Dashboard Sunshade
For those times when you're not driving, but the car is still out in the sun, a cover that goes in the windshield will protect the dashboard against ultraviolet rays and help the cabin stay a little cooler. Some even have solar panels to keep the battery charged. Consider shades for the rear side windows, too, as they'll provide some protection for the kids. This also helps prevent areas such as the rear seats and dashboard from fading over time.
9. Clean the Car
Those long, balmy evenings when the sun is a huge, orange orb hanging low in a pinky-blue sky sound blissful. But they can also be a hazard, especially when your car's windshield is dirty. Even from the inside, that haze will diffuse the light and make things hard to see. That grime has a tendency to build up over a long period, so we don't really notice it. Things look much sharper after your car has had a good wash, though. Keeping the exterior clean also protects the paintwork from the sun's rays, as well as any damage caused by birds and insects. Finish off the cleaning with a good-quality wax. Car care makes financial sense in the long run.
10. Driver and Passengers
It's hot out there. Make sure everyone's hydrated. It's better to make a few more bathroom breaks and stretch your legs than to end up cranky and fatigued. Plan road trips as if you were a general marching against an opposing army. Make a list of everything you're going to need. For example: sunglasses, hats, travel mugs, games for the kids, snacks, chargers for the phones and tablets, route planner, weather forecasts, emergency triangle, flashlight and a small tool kit. If a scheduled service is coming up, think about getting it done before a long drive. It's also wise to make sure your insurance and driving license are up to date. Have a great summer, enjoy the roads, and take care of yourself and your car.