Just found this article online at Jeepgarage.org and thought some folks might be interested and it covers your question about wheels. It was written by, Tom Torbjornsen.

Nobody in their right mind would want to void their car warranty. Yet, there are thousands (perhaps millions) who worry that one small thing will crumple their precious warranty up and throw it into the waste basket. A portion of those people have written to me lamenting the fact that they did something that voided it. So what are the most common actions that result in a voided car warranty?

What Is A Car Warranty?

First of all, in order to understand your part in the warranty relationship, it is vital that you understand what a warranty is and what it is not. A new car warranty is an agreement between the carmaker and the consumer. It outlines what you must do to keep your warranty in force, and a warranty can be voided in part or whole. For instance, if you don't have the oil changed in the engine according to the suggested maintenance schedule and the engine fails as a result, the carmaker has the legal right to void the warranty on the engine. The rest of the warranty remains intact, providing nothing else was affected by such negligence.

There are also warranty issues related to the installation of aftermarket products and/or services on a vehicle that is still under a new car warranty. Often people install aftermarket products for adding customizing features or they use certain services for vehicle maintenance. The Magnuson Moss Warranty Act addresses such issues. This law states that if a customer installs an aftermarket product (it could be a fluid, filter, hard part, software...virtually anything that was not installed on or in the vehicle from the factory when it was new) and if the vehicle fails as a result of the installation or use of the aftermarket product/service, the carmaker cannot arbitrarily deny a warranty claim and/or void the new car warranty because of the installation or use of the aftermarket product, but must prove beyond a shadow of a doubt that the failure was indeed caused by the installation or use of the aftermarket product. The reason this law was put into place is because carmakers were arbitrarily voiding car warranties and refusing warranty service because the customer had installed an aftermarket products/services. Since there was no required burden of proof on the carmaker, consumers were hung out to dry. The Magnuson Moss Warranty Act forced the carmaker to prove that the failure was due to the aftermarket product. The law still stands today within the U.S.

Common Ways People Void Their Car Warranty

At this point, you know that a new car warranty is an agreement where both parties have obligations. And you know that, as a consumer, you have certain legal safeguards against arbitrary decisions on the part of the carmakers. Now let's take a look common errors people make that can void their warranties.

Fluids: Use the proper fluids specified by the carmaker
Carmakers dump millions of dollars into research and development to determine the best fluids to put into their vehicles for maximum performance and longevity. So why do people continue to use what they think are the best fluids for their new vehicles? For example, a woman called my national radio show a couple of years ago crying on air that, when her husband changed the oil in her new Ford Taurus (3.0 liter V6 engine), he used straight 30-weight, non semi-synthetic motor oil and the engine had failed. When the oil was analyzed, it was found that the oil didn't provide proper lubrication to the engine and was the cause of the failure. Lack of proper rod and main bearing lubrication was cited as the key cause for the engine failure. Ford specifies using 5W20 semi-synthetic oil in that particular engine; hence the warranty claim was denied and the engine warranty voided. The point? Use whatever fluid the carmaker specifies in your car to keep your warranty intact. In this case, Ford was completely within their rights to void the engine warranty.

Receipts: Make sure you keep 'em (All)
Keep all receipts on any maintenance work done at facilities other than the dealership while your car is under warranty. Some people do not return to the dealer for service after buying a new vehicle. They have their vehicles serviced at quick lubes, their local repair facility, and/or anywhere they can find a deal. It's okay, as long as the service provider uses the specified fluids and OEM (original equipment) quality filters. So what's the problem? A lot of folks don't keep records and receipts. They have no documentation proving that the services were done according to mileage intervals as specified by the carmaker. When it comes time to file a warranty claim, the carmakers will ask for proof that the services were done. No receipts? No warranty coverage. This is one benefit of going to a dealer for regular maintenance while under warranty; the carmaker requires that they keep meticulous records. When and if a warranty claim becomes necessary, the dealership simply transfers all vehicle records electronically to the proper people for processing.

Tires and Wheels: Don't use non-conventional tire/wheel combinations or modify the suspension
One of the major crazes these days is installing "Dubs," (aka twenty-inch wheels) and making dramatic suspension modifications using extreme lift or lower kits. Base vehicle designs are compromised by such modifications. These include conventional alignment angles, vehicle undercarriage components, and drivetrain components such as axle bearings (due to extreme offset of the wheel hub on some wheels). Such compromise can result in steering, suspension, and drivetrain problems. In the event of a warranty claim related to these systems, the carmaker will scrutinize the modifications. If the failure is due to the installation, the warranty claims are denied.

Performance Modifications: Don't modify or "chip" your car
A few years back, Ford issued a TSB (Technical Service Bulletin) regarding blown head gaskets on 6.0 Powerstroke turbo diesel engines in F series pickups (2005 and up). A rash of pickups were coming into shops across the country with blown head gaskets. The common thread? Power chips were installed to boost engine output. According to the TSB, on trucks with blown head gaskets, techs were to check for the installation of a power chip, which increases engine power by modifying the drivability and engine management parameters. Part of the programming modification on these vehicles included increasing turbo boost (which increased combustion chamber pressures), thus blowing head gaskets. In such cases where the vehicle was under warranty, claims were denied and engine warranties were voided. In this case, the carmaker confirmed that head gasket failure was indeed due to installation of the power chips. The carmaker was well within their right to deny claims and void engine warranties.

Towing: Don't tow a trailer with a vehicle that is not designed to tow
In order to tow a trailer, a vehicle must have an increased cooling system capacity, auxiliary trans oil cooling, beefed up rear frame area to support the hitch receiver, beefed up suspension to handle the additional weight, heavy duty brakes to stop the increased load, and special wiring to power the trailer lighting. Typically, vehicles used for towing that are not properly equipped experience an overheated engine, overheating of the transmission (and internal damage), frame damage, suspension damage, excessive brake wear, and compromised wiring (causing electrical shorts and malfunction of lights). Oh, and let's not forget the poor handling and safety hazards an overloaded vehicle presents to both the driver and other motorists on the roadways. If any of these issues arise as a result of towing with a vehicle that is not designed for it, warranty claims will be denied.

Obviously this is a complex topic, and there are many other actions that would result in voiding part or all of your new car warranty. My advice? Follow this rule of thumb: Before doing ANY modification or using ANY products or services other than OEM recommendations, as specified by the carmaker, check with your car dealer before proceeding.

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'20 Ranger Lariat FX4 Oxford White