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The Truth About the Magnuson Moss Warranty Act

The Truth about this Historic Law, Concerning Aftermarket Parts

Alright, so here’s the deal. Before we go any further into products and installs, such as tuning or exhaust modifications, because we value honesty and transparency around here, we’ve gotta lay it all on the line.

While in general, I can say that most (probably all) of the aftermarket parts we sell here at Midwest Aftermarket will never ever void your warranty, I’ve got to explain why and how the Magnuson Moss Warranty Act works, how it protects you, and what the limits of that protection are. First the quick version and FAQ’s around this historical law.

The Truth about the Magnuson-Moss Warranty Act

What is the Magnuson Moss Warranty Act?

What does Magnuson Moss mean for the aftermarket community?

The Magnuson Moss Warranty Act prohibits automobile manufacturers and dealers from voiding a vehicle’s warranty because an aftermarket part or a part not made by the original manufacturer was installed on said vehicle.

Alright, What about adding rear spoilers? Will that void my warranty?so let’s translate that into regular people speak: your warranty for the most part will NOT be voided because you’ve installed an aftermarket part. Good. This act also prevents the dealer from requiring you to have all your repairs done at the dealership or from only installing replacement parts that are OEM.


While the Magnuson Moss Warranty Act covers a lot, if not nearly all, of the products you might install on your vehicle, things do start to get kind of complicated when we get into any particular part that might modify or change the way that your vehicle was intended to operate. So we want to make sure you know exactly how this all works before you dive into making major purchases of Aftermarket parts.

What is the specific wording of the Magnuson Moss Warranty Act?

Here’s the legal wording:

“No Best read the fine print of that warranty!warrantor of a consumer product may condition his written or implied warranty of such product on the consumer’s using, in connection with such product, any article or service (other than article or service provided without charge under the terms of the warranty) which is identified by brand, trade, or corporate name…”


Now here’s the problem with that wording… say what?

Basically, Say what?! Let's try to translate that.having your vehicle serviced by someone other than the dealer and/or installing a part not made by the original manufacturer will not automatically void the warranty. It is in fact illegal for your dealer/manufacturer to have anything in your warranty that states you must have your service performed by them or that you must buy your replacement parts directly from them either.


The FTC has since found that this covers Aftermarket parts as well. But we should read that statement very carefully. So the FTC Consumer Alert released a statement titled “Auto Warranties, Routine Maintenance, and Repairs: Is Using the Dealer a Must?” And in this document there is specifically one section that mentions “aftermarket parts.” The following section of this article contains quotes taken directly from this report.

FTC Consumer Alert:

“Will using ‘aftermarket’ parts void my warranty?”

In other words, does installing an aftermarket part automatically void my warranty?

“No. Will using aftermarket parts void my warranty? NOPE!An ‘aftermarket’ part is a part made by a company other other than the vehicle manufacturer or the original equipment manufacturer. Simply using an aftermarket part does not void your warranty. The Magnuson-Moss Warranty Act makes it illegal for companies to void your warranty or deny coverage under the warranty simply because you used an aftermarket part.”


Okay. So far, so good. But read on very carefully because we are getting into lawyer territory here:

“Still if it turns out that the aftermarket part was itself defective or wasn’t installed correctly, and it causes damage to another part that is covered under the warranty, the manufacturer or dealer has the right to deny coverage for that part and charge you for any repairs. The FTC says the manufacturer or dealer must show that the aftermarket equipment caused the need for repairs before denying warranty coverage.”

And there’s the questionable part. Up until this section, the FTC Consumer Alert and the Magnuson-Moss Act made it sound like there was no way in hell that installing an aftermarket part would void your warranty. And technically that’s true, until you run the vehicle. Sigh.

If the dealerHard to swallow that nonsense about warranties. can prove that installing the aftermarket part lead to the failure or damaging another part that was originally covered by the warranty, well, then frankly, you’re sh!t out of luck. Now before you panic, we’ll show you how to cover your @ss below. But we do want to make this clear: installing something will never void the warranty. But using a product that changes the way your vehicle was intended to operate, that the dealer might be able to argue caused additional damage to original parts, could void your warranty or cause the dealer to require you to pay for those specific repairs that were allegedly caused by the aftermarket part.


The Truth about the Magnuson Moss Act

So the truth is, based upon what we just learned, there are some aftermarket mods out there that would most likely void your warranty. However, most (probably all) of the products we sell here at Midwest Aftermarket should not have any danger of voiding your warranty. I say “most” because you never really know until you get a landmark legal case. So for now, as of this second, everything we sell has not ever voided a vehicle warranty to my knowledge. But the way our legal system works here in the US, all it takes is one case to change this.

I can pretty much stand by this though, because most of the products we sell don’t modify the way your engine operates or the intended way any part of your vehicle operates. Installing some fender flares or a step bar or even a larger wheel and tire isn’t going to change your engine’s factory settings. Hence you aren’t in any danger of voiding any warranty with these products. Putting on some Window Visors doesn’t change the way your windows function.

But rather than focusing on the safe zones covered by Magnuson Moss, why don’t we get into the stuff that we know for a fact will most definitely void your warranty if your dealer catches you with one installed.

NOS will Probably Void your Warranty

For instance, consideringNOS will probably void your warranty, if you get caught with it. something we do NOT sell: installing a NOS (or Nitrous Oxide) system will most likely void your warranty. Here’s why: it involves a direct change to the way your vehicle was designed to function. The manufacturer made your truck or Jeep or car to run on a specific fuel, be it diesel, gasoline, E85, whatever. And to my knowledge, no original manufacturer has created a stock engine that’s meant to run even momentarily on Nitrous.


Hence, if you were to bring your vehicle in to the dealer with a warranty claim and it had something to do with your engine, and they noticed your engine had been modified to include a NOS system, chances are they would not cover the charges to make those repairs and would blame the issues, even if it wasn’t necessarily due to the NOS, on the NOS, if that makes sense.

Now we don’t sell anything like that, and I will tell you buyer beware on that kind of mod. When you start changing up the fundamentals of how your engine works, chances are your warranty is going to go out the window. Now that same scenario would not necessarily mean that your warranty wouldn’t cover something non-engine related like say your window motor failing or a seatbelt issue. So bear that in mind before you tell your bro that the warranty is void just because he installed NOS. Cause that isn’t necessarily the case either. It all depends.

Performance Tuners: Will Programmers Void my Warranty?

Maybe, but not if you are smart about your install. If the dealership can prove that the tuner somehow is responsible for the damage to whatever part you are trying to make a warranty claim on, then you may get stuck with the bill for that repair, though it is highly unlikely that this would void your warranty.

In the nameFacepalm: leaving your tuner plugged in when you take your vehicle to the dealer for some work. of complete transparency, we carry one kind of product that could possibly fall into this category, and its performance tuners. If a dealer was really trying to screw you over, it is technically possible that they could try to blame something on a tuner. This wouldn’t void your warranty, but it could become a huge hassle if a dealer was trying to make you pay for a repair that should be covered by your warranty. So same difference, if you will.


Here’s how you make sure you don’t end up in this limbo area.

First, this is not super likely to happen. Most dealers don’t even notice that you’ve modified your ECU or PCM unless if they have a reason to go looking. Heck, I traded in my last vehicle with a modified custom tune installed on the PCM, and nobody was the wiser.

What should you do if you are using a performance tuner and want to take your vehicle into the dealership or for EPA emissions testing?

How do I make sure the EPA or my dealership doesn’t know I’ve been using a programmer?

Three simple steps for making sure your dealer and the EPA are none the wiser:

Reset to Stock Tune

If possible, Unplug and Remove the Tuner

Don’t tell the dealer/EPA you were using a Programmer/Tuner

I know, right? It’s crazy simple. Heck, even if you just do step one, use your tuner or programmer to reset your ECU/PCM back to Stock settings, you’re pretty much in the clear. The EPA is just going to hook up their own little computer to the OBDII port. They’ll be none the wiser unless if you have something plugged into that port already. If you forget and leave the tuner plugged in, try this one that my buddy used one time:

Tell them that the tuner is actually one of those vehicle monitor systems that insurance companies use now. He had one from Progressive. It tracked how fast he drove and how hard he braked, and if he stayed within certain parameters each month, they’d give him a sweet discount for his insurance that month. Fun times and possibly true? Certainly believable.

As for the dealership, as long as you reset to stock and remove the tuner, all they will be able to tell using their own diagnostic tools via OBDII port is that something has been plugged in. If they ask, and it is doubtful they will, tell them you were checking a DTC or Diagnostic Trouble Code that popped up on your display. This could be anything from “Low Tire Pressure” to “Oil Change” to “Low Battery.”

It is completely legal for you to check these codes, and you don’t have to even own a DTC checker to do so. Most auto parts stores will check the codes for you. So if the dealer asks, which is highly unlikely, just tell them that you took your vehicle down to the local auto parts store to check a code and found out your internal air filter needed changed or something like that. While you’re at it, you might consider checking your internal air filter. I know I always forget about to clean and replace that one.

So basically, unless you really screw up and leave your tuner plugged in and then bring it to the dealer or EPA’s attention, you should be fine.

Pro Tip, if the EPA catches you with a tuner and gives you hell, try coming back on another day without the tuner and with your engine programmed to Stock. In most States (if not all) they have to give you an opportunity to make necessary repairs or adjustments to pass emissions testings at least once. Do double check though because they may make you wait a week or two in between. That happened to me once simply because I had unplugged my battery. Oh, check that, by the way. Something as simple as unplugging or replacing your battery within a week of having an emissions test can cause the equipment used to make the test--a sensor--to not show as active and hence mean you’ll have to come back and get tested on another day. Found that one out the hard way. Thanks, EPA.

So what’s the big deal about the Magnuson-Moss Act?

I’ve gone on and on about this one, I know. And part of it is because I have lived in areas before here in the US where I had to get emissions tested once a year. Fun times.

Part of it is because we want you to be informed before you make purchases, and we don’t want you to get stuck holding a bill because you left your tuner plugged in.

But the biggest reason we wanted to bring this up isn’t because of warranty claims or the EPA. The real reason is that--while we don’t know about you personally--we know people, not unlike ourselves, who’ve been hassled by dealerships when making truck purchases and when trading in modded trucks.

Yeah. We’ve been there.

Have you ever heard this line before from a salesperson at a dealership: “Installing that tuner will void your warranty?”

Or: “That [insert aftermarket part here] is going to lower your trade-in value.”

Well, because we’ve been dicked around in the past, we thought we’d give you these words as ammunition: “Magnuson-Moss Act.”

Simply installing an aftermarket part will not void your warranty. So don’t let some dealership crony try to bully you into not getting or using your performance programmer. Likewise, if you’re trading in your truck and some cocky salesman tries to tell you that your step bars or fender flares are going to lower the trade-in value, don’t believe it.

Just like you installed those products to make your truck more cool or more functional, there are thousands of other people just like you who would pay extra for such mods. Heck, many dealerships even have “stock” trim levels now that have added “aftermarket” like products, such as step bars. So don’t guy it when they tell you this nonsense. And if the one dealership gives you hell about it, tell them you can always take your business elsewhere.

The Truth about Warranties

While I’m Extended Warranties are a rip off!pretty much done explaining the Magnuson-Moss Act and everything you need to know before modding your ride, I do want to emphasize one more small detail. So this Warranty Act is all about--you guessed it--warranties. And here’s the thing: warranties have kinda gone down in quality over the years to such an extent that (and I know most of you know this already, but I feel like I gotta say it anyway):


Most Warranties aren’t worth the Paper they’re printed on these days.

Especially Extended Warranties on Automobiles! Please, please, please! Don’t pay extra for that crap! Please! (I’m screaming at my wife here, now.)

Find out why in my upcoming BlogPost: The Truth about Warranties. Coming soon to a Midwest Aftermarket Blog near you!

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