Change the oil
You have probably heard this a million times before, but this particular point ears repeating, especially if you live in a climate with harsh winter conditions. Oil designed for cold weather use cannot provide proper lubrication in hot weather because it thins out too much. Replace the oil with the grade recommended for summer use, and don’t forget to replace the filter as well.
If your wallet can stand the extra strain, replace the oil with fully synthetic oil, even if it is not specifically recommended by the manufacturer of your vehicle. Synthetic oil remains stable under a wider range of temperatures than regular mineral oil, with the added bonus that it provides almost twice the lubrication of mineral oil, which is good for any engine, and especially older, high mileage engines.
Replace the engine coolant
You have no doubt heard this a million times before as well, but proper auto maintenance requires that the engine coolant be replaced at least once a year. Apart from lowering the boiling point of water, the correct concentration of anti-freeze also prevents the corrosion of aluminum engine parts and components, which can cause serious issues, including engine failure.
Internal corrosion can open up leak paths through which coolant can be lost either to the outside of the engine, or into cylinders where it interferes with the combustion process. Coolant can also leak into the engine oil, with potentially disastrous results if the problem is not caught and resolved in time.
However, always follow the manufacturer’s recommendations regarding the amount of anti-freeze to add to the cooling system. Too much is as bad as too little; too much anti-freeze actually lowers the boiling point of water, meaning that your engine can overheat even though you have just replaced the coolant.
Check the battery
Hot, humid conditions kill more car batteries than even the coldest winters, so cut down on unexpected auto maintenance and maintenance costs by ensuring that your battery is up to the demands of summer conditions. Even marginally defective batteries can cause all manner of electrical issues, such as sporadic or unexpected trouble with alarm/security/anti-theft systems, low fuel pressure, difficult starting, or even rough idling, and/or rough running- among others.
Have the battery tested at a specialist battery dealer, and check that it can deliver the required cranking amps. Replace the battery if there is even the slightest doubt about its condition.
Remove road salt
If you live in an area where the roads are treated with salt during winter, be sure to have all salt deposits removed from the wheel wells and other places where slush tends to collect. Salt is highly corrosive, and not removing it will definitely cause rust and corrosion to set in. Once corrosion sets in, it may be impossible to stop or remove, so be sure to have all traces of salt removed as soon as the weather improves.
Check tires and tire pressures
Proper auto maintenance includes checking the condition and inflation of all tires, including the spare wheel. Tire pressure is as important as tire tread depth, so as soon as the weather improves, adjust the pressure in the tires to allow for heat expansion. High ambient temperatures and hot road surfaces can cause the air in a tire to expand, which can increase the pressure inside the tire by as much as 15% or more.
Never rely on the tire pressure monitoring system to warn you of under inflated tires. These systems are notoriously inaccurate, and a tire can be under inflated by as much as 25% before an alarm or warning light is triggered. Use a good quality digital tire pressure gauge to check your tire pressures at least once a week to maintain tire pressures at the recommended level.
Check the A/C system
In some climates, proper auto maintenance involves ensuring that the air conditioning system is fully functional, so avoid the rush and have your A/C system checked out before summer really sets in. Listen out for any unusual noises, sounds, or odors coming from the system, and have all faults repaired before a minor issue becomes a huge problem.
The best way to maintain an air conditioning system is to use it- even in the depths of winter. This not only keeps all the moving parts in the compressor lubricated, but it also largely prevents micro organisms from establishing colonies in the system’s ducting. So if you have not used the A/C system during the past winter and it now gives of an odor that smells like something had died in it, you have an unwelcome growth of bacteria, mold, and/or fungi in the system.