Sorry for your frustration
Here’s copy of the Federal Magnuson-Moss Warranty Act that specifies your rights.
I hope ithelps to resolve your issue.
When accessorizing your vehicle with aftermarket parts, your warranty claim cannot be automatically denied, nor can your warranty be voided, if you install non-OEM parts in your vehicle. The burden is on the dealer to prove the aftermarket parts caused the failure. For example, if your windshield wiper motors fail, your vehicle’s warranty claim can’t be denied because you installed aftermarket performance programmer, tuner, chip, etc. Similarly, if a wheel bearing fails or a fan belt snaps and you have an aftermarket exhaust installed, the dealership would have to prove the exhaust system caused the bearing failure or the belt to snap in order to deny a warranty claim. In these types of scenarios, the dealership should have no reason to deny your claims.
In addition to the Magnuson-Moss Warranty Act, you also have SEMA (Specialty Equipment Market Association) working to protect your rights. Because SEMA represents U.S. aftermarket wholesalers, retailers, distributors and manufacturers, they often keep car manufacturers in check by supporting legislation that prevents dealership service providers from denying warranty coverage. This means dealerships have become less stringent when it comes to aftermarket parts that modify performance or suspension.