First. Always read every line of your warranty. Even if you do it a few pages at a time, you need to know exactly what is allowed and what isn’t.
Things that can void a car warranty.
Using an unapproved Mechanic.
Letting your brother work on your vehicle is certainly much cheaper, as is doing it all yourself but many contracts specify who can work on the car and who cannot. If they are not licensed, don’t let them touch it, even if they know what they are doing.
Using the wrong parts or fluid.
Almost every warranty states which parts manufacturer should be used, as well what brand of fluids. Something as simple as using 1 quart of the wrong oil when you are in a hurry or low and the store doesn’t have your brand, are one of the easiest ways to void a car warranty.
Going over the mileage.
When you buy a car, you fill out forms that tell them how much you drive a year and this is averaged and put into your deal. If you go over on that mileage you can be charged extra, as well as ruining your coverage.
Letting someone else drive.
Anyone who is not listed on the warranty should not drive. That will void it faster than anything else. Your coverage is only for yourself unless otherwise specified. Some people do not worry about this rule and discover later that the car company found out by something as innocent as being in the wrong place at the wrong time,(same grocery store) all the way up to having you followed and taking pictures.
Having an accident.
Whether the damage is small or large, your fault or someone else’s, having an accident is most certainly one of the things that can void a car warranty. Make sure you read that part of the contract until you understand it. For those who are accident-prone, adding an exemption is a good idea.
Not getting the oil changed on time
Yes, something that petty. Even a day over your assigned time will come back to haunt you. As one of the most clever things that can void a car warranty, not changing the oil on time is an easy mistake to make and costs car buyers millions every year.
Not being able prove you’ve followed the contract.
Not keeping receipts is the kiss of death. In one folder, place a small white envelope for each of the parts in your contract, such as oil changes and parts.
Add receipts from everything you have done or do to the car. Be meticulous. Even a single missing document is one of the most common things that can void a car warranty.