Check also for the appropriate coolant flush and change frequency. Inspect and replace worn or cracked belts, as well as hoses that are worn, cracked, blistered, brittle or too soft. Check the level and condition of engine oil. When driving under extreme conditions such as 90 to 100-plus degree temperatures or towing a heavy trailer, switch to heavier motor oil. Since high temperatures compromise battery life, test and replace old or weak batteries if necessary.
Heat can affect transmission fluid by making it thinner and less effective.
Check the transmission fluid to be sure that it is at the proper level and doesn't smell burnt or look dirty. This is especially important for vehicles that are used for towing. Check the owners manual for the right type of the transmission fluid to use. High temperatures also can lead to pinging in the engine. If pinging continues, the Auto Club recommends using a higher-octane fuel to eliminate the noise.