The dealer could technically deny the factory warranty if they can prove (or simple think, then you'd have ro dis-prove) that an aftermarket filter caused the damage. Goes with any aftermarket part with respect to a factory warranty.If the aftermarket meets or exceeds oe they cant say squat.
They can't deny warranty on the whole vehicle due to using an aftermarket part. Some makers like Ford have denied warranty on something by making excuses to get out of warranty coverage, which is wrong and against the Magnuson Moss warranty act. Example: I've heard Ford deny warranty on the power window motor failing because the ECU had a tune. How can a tune cause a power window motor to fail? It can't, and Ford is abusing the MM warranty act in a case like that.
Last edited: