This is a topic that often comes up, and the short answer is “they may have the potential to”.
Different manufacturers have different warranty protocols and procedures so to give a proverbial yes or no at this point would be misleading.
What we can tell you however, is what we have come across in our dealings with the manufacturers on a day in day out basis. Essentially, the manufacturer will warrant a product, component, or part against manufacturer defaults – if you have a legitimate issue with your exhaust, the manufacturer is obliged to replace it, assuming all other circumstances are in line. If you are going to replace your exhaust with an aftermarket option, then obviously the manufacturer is not obliged to warrant a separate product. The product we fit for you however, will come with its own manufacturer warranty, so one is covered under that basis.
Where the grey area arises is when there may be a claim where the cause of the damage is unknown, or a little less clear-cut. For example, for a manufacturer to deny a warranty claim on an engine failure due to the fitment of an exhaust system, the manufacturer must prove that the exhaust has directly attributed to the component failure – it is illegal for them to do otherwise. They cannot deny a warranty claim on an engine on he grounds of you fitting aftermarket suspension. Make sense? However, if the fitment of the aftermarket part has in some way contributed to the failure, whether it be as a result of extra undue stress on components or incompatibility issues, then there is a chance the manufacturer will be able to deny a warranty claim.
The one thing to keep in mind here is that mechanics, manufacturers, service centres and the likes are all very intelligent – we generally find the main cause of component failures to be sheer user error / mistreatment. Component autopsy generally never lies, and if one blows up their engine being an idiot, the evidence will be there in black and white for the inspector. Regardless of whether you have an aftermarket component fitted or your car is dead standard – your claim will be voided. On a rare occasion, component failure will result from legitimate reasons relating to ones modifications – some engines were just not designed to tolerate some of the incredible gains in power and torque that are achievable via modification. This situation is not a manufacturer fault, and will also likely result in a voided claim. The key here is to be intelligent regarding the chosen modifications and knowing where the boundaries lie (and this where we can help you).
The bottom line to the situation is to be as best informed, educated, and aware of the potential consequences. We have yet to have a customer denied a legitimate warranty claim from a manufacturer on the basis of modifications completed by us. We even regularly perform “pre delivery” modifications on brand new vehicles direct for dealerships and customers, and these vehicles are still sold with a manufacturer full warranty. The key is being as best informed as possible – if you have any further questions, give us a call and I will be happy to explain in further detail.
One final addendum – we will soon be implementing our own in house warranty and protection programs, which are designed to give you the consumer, the added protection knowing that if a manufacturer warranty claim is denied, you may very well still be covered under the terms and conditions of our own specific warranty protection package tailor made for modified vehicles. Stay tuned for more details on this one shortly.