Car tires start ageing the moment they are manufactured and will slowly start deteriorating as time goes by. Although tires are made really tough, they are not indestructible and could be susceptible to tire dry rot. Tire sidewall cracking is another term for tire dry rot and a more descriptive term for it. Under normal conditions, the tread will run out before tire dry rot will set in, in fact, tires are designed to be driven on frequently. Dry rot is when the rubber in your tire starts to break down. Cars just sitting there and not being driven will cause the tires to develop tire sidewall cracking much earlier.
Tires kept healthy and away from extreme conditions could last up to 10 years, which is the maximum age a tire should be to be legal. After 10 years it must be recycled and would be unsafe to drive on. All the chemicals protecting the tire would all have disappeared, and the tire will become brittle and weak.
Using Plasticizers in tire manufacture
Natural as well as synthetic rubber is used in tire manufacturing. Synthetic rubber makes out about 70% of the rubber used in making a tire, while natural rubber only makes out 30%.
Crude oil is used to make synthetic rubber, and about 7 gallons of oil is used to manufacture one tire. Plasticizer in tire manufacture mainly consists of crude oil and resins and is used to make the tire more flexible and reduce rolling resistance. It also keeps the tire soft in cold weather and improves grip. The “green tire” tread compound gets plasticized by different types of resins with the purpose of strengthening the rubber and lessening rolling resistance and improving grip in wet conditions. Resins are also used in the vulcanization process where the tire gets baked and via chemical reactions hardens. This result in a much stronger tire which is more durable. The resin protects the tire and helps to keep the tire oils inside.
What does this have to do with tire dry rotting?
For the tire to function the way it is supposed to it needs to keep the oil and moisture inside the rubber. With age and extreme environmental conditions, this protective resin disappears and exposes the rubber to oxygen. Oxygen dries out the tire and will result in the essential oils in the tire leeching out. The tire will lose its elasticity and will become brittle and weak. It will also start losing its black color to become grey and cracks will start to appear on the sidewall or even cracks in the tire tread. and tire dry rot will start to settle in.
Driving with tire sidewall cracking:
The tire will keep drying out and will progress to its final stages of tire dry rot. Small cracks will become larger and go deeper in the sidewall and tread weakening the tire even more. Tire dry rot also sets in from the inside of the tire and the tire will start to leak air and will start to break down. The tread can even get totally ripped off the tire while driving causing a blowout and a total loss of control of the vehicle.
How to prevent tire dry rot or at least delay the effects of tire dry rotting, and increase tire lifespan
Avoid parking the car for weeks or months without driving it
Car tires are designed to be driven frequently. It needs motion and downward pressure from the car to activate the resin in the rubber to protect it from ageing and drying out. If you have to park your car for an extended period of time, park it in a garage. If it is parked outside use a cover that extends all the way down to cover the tires as well to protect it from tire dry rot.
Avoid chemical spills
When you park your car in a garage or outside you should stay clear of corrosive chemicals like industrial cleaning products, motor oil or pool cleaning chemicals. Also, avoid any petroleum-based solutions when treating your car tires, this will have a deteriorating effect on the protective agents of your tire and can cause tire dry rot to settle in much faster..
Parking the car out of direct sunlight or extreme heat to prevent weather cracked tires
Rather park your car in a garage or at least in shade to protect the tires from being damaged by direct sunlight. The sun’s UV rays will damage the rubber and ageing of the tires will occur faster. Especially the sidewalls where cracks might start to appear after prolonged direct sunlight. Special care must be taken in warm, dry and desert-like areas to prevent weather cracked tires. Excessive heat buildup in the tires will certainly speed up the process of tire sidewall crackng. These areas are also susceptible to sub-zero temperatures at night and these temperature fluctuations will damage the rubber and cause it to dry out and break down.
Weather cracked tires caused by extremely low temperatures
Especially using summer tires in an extremely cold environment will cause the tire to age fast and tire sidewall cracks to appear. Stock tires, also called summer tires are not designed to deal with extremely low temperatures. When temperatures fall below 7 degrees Celsius it will harden and become brittle. Winter tires can handle much lower temperatures because they have more plasticizer in the rubber to keep it from hardening. Winter tires in sub-freezing temperatures are also susceptible to tire dry rot and will get damages by such extreme cold.
Properly inflated tires
Check your tires weekly to make sure they are at the manufacturer’s recommended tire pressure. Check the pillar on the driver’s side or in the car manual for the correct pressure. Driving with under-inflated tires will generate excess heat and will wear the tires faster on the outside edges. Tire sidewall cracks will start to appear while driving your car with under-inflated tires for prolonged periods of time.
Conclusion
When it is still in the early stages of tire dry rot, you can treat the tires to give you a bit more mileage and delay the dry rotting process. You can use water-based tire oil if the cracks aren’t too deep yet but avoid silicone and petrochemical-based oils.
They do more harm than good. Apply it monthly to keep the protective layer on the rubber. Tire dry rot puts the tire in a weaker state, and they should be replaced sooner than later. Especially when sidewall cracks and cracks in the tread are getting deeper.
When you live in areas with extreme temperature changes where chances of weather cracked tires is at its maximum, you can still do your bit to delay tire dry rot of your tires. Just by being aware and making sure you don’t expose them unnecessarily to environmental or climatic extremes or exposing them to deteriorating and corrosive agents lying around.
