If you install aftermarket parts and you have a failure in that particular area of modification, you may have warranty issues unless the part in question actually CAUSED the problem that the warranty claim is about. For example, if you install aftermarket shocks, and then your turbo blows, the manufacturer cannot deny you warranty coverage on the turbo. (Unless the shocks somehow directly caused the turbo failure, which defies reason.) But if you install an ECU chip upgrade that increases turbo boost, and then your turbo fails, the manufacturer could probably deny your claim. It is reasonable to think that increased boost could lead to a turbo failure. A performance chip may void the warranty. If your engine blows and a technician finds that it is chipped, he can deem that it was to the performance upgrade. It can be said that the engine was over revved from racing. A lot of people choose to raise the performance of the vehicle to boost it’s power and speed. But some cars were not designed with performance modifications in mind. You can install a high flow air filter and exhaust. Replacing the camshaft with one that keeps the valve open longer will increase some power. Depending on the degree of cam lobe lift engine performance can be adjusted to give more power through the RPM range. Some dealerships do performance modifications that are compliant with manufacturer regulations. Racing the vehicle is a sure way to void your warranty. If your car’s odometer has been disconnected, tampered with or replaced, the dealer cannot determine the exact mileage. This is usually grounds for a voided warranty. There’s no surefire way to know if your odometer has been tampered with, but if you order a vehicle history report, the dealer can check for inconsistencies in mileage reporting. I have seen this during my career. Especially on luxury sports cars. The instrument clusters were replaced with a unit having lower mileage. Clusters are expensive, but when you are selling the car with low mileage on it you can make up for the difference. Simply having an aftermarket part or modifying your vehicle cannot void your warranty. However, if the reason for a parts failure is unclear, a dealer will usually charge you to diagnose the vehicle. If the aftermarket part was not properly installed or a modification led to a component failure, it is within the dealer’s right to void the warranty for that part, and you will have to pay for the repairs out of pocket. If the aftermarket parts had nothing to do with the repairs in question, you will be refunded the fee for the diagnosis. Any aftermarket performance parts on your vehicle can cause a dealer to suspect that you either drive the car hard or possibly race it. Although they may not void warranties, modifications may raise a red flag when vehicles are in for service.
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