Be Careful with Aftermarket Products

• The fine print in an auto manufacturer's warranty contains detailed information related to aftermarket products. The disclaimer allows the manufacturer to deny a warranty claim if they feel an aftermarket product you have installed has possibly contributed to the defect. They don't have to prove the product caused the defect; they only have to have reasonable suspicion. The best way to avoid this is to use the manufacturer's accessories rather than using the aftermarket. Each auto manufacturer offers accessories available through the dealership or their website. While the prices may be higher, the cost of genuine factory accessories is nothing compared with the cost of replacing an engine or another major vehicle component.
  
  

Keep Detailed Service Records

• Auto manufacturers recommend you have the vehicle serviced at one of their dealers; if you choose to have it serviced elsewhere, it is highly recommended to keep copies of all maintenance performed. When you have service performed at the dealer, the manufacturer has access to this information; if you choose an independent shop, the only record may be the paper copies of service receipts you keep. Oil change receipts may come in handy if you have a major engine problem and the manufacturer has no record of you getting the vehicle serviced. Without service records, they will likely deny the warranty claim and leave you stuck with the bill.
  
  

Don't Abuse Your Vehicle

• Modern vehicles use advanced computer technology to keep track of engine diagnostics. If your vehicle shuts down or has a major problem, the computer records detailed information about the conditions at the time. It records your speed, engine rpm (revolutions per minute), operating temperature and other records. When the dealer submits the diagnostic record, if the manufacturer feels you were abusing the vehicle (running it too hard), they will likely place the blame on you and deny the warranty claim.