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Exhaust or Cold Air Upgrades Void the Warranty??? That's what I was told..

When I traded my 2012 GT for a new '12 Boss 302, I asked the lead mechanic if he could install the Kooks axleback exhaust that I had on my GT. He told me that any modification whatsoever would void the warranty including changes to the exhaust system. I was getting back the aftermarket cold air intake from my GT and he said that it would also void the warranty.

When I went to an independent exhaust shop today to have the restrictor plates removed for a more aggressive sound, the owner and another mechanic there told me they didn't see how my axleback would void the warranty. They also told me I should keep the restrictor plates on and just swap out the stock mufflers for the Kooks ones.

So now I'm confused. I really liked the Kooks sound on my GT and I want a more aggressive sound on the Boss, but I don't want to do anything that will void the warranty. At the same time, I'm wondering how all these different companies are slowly coming out with various mods for the Boss if any of these would void the warranty (i.e. exhaust systems, cold air kits, tunes, etc).

Can anyone help me out? Thanks,

Brian
 
they cannot void, by law, a full warranty.
read up on whats called the consumer bill of rights. it goes into depth.

they can flag the car ect saying that yes, you have long tubes ect....but its up to the dealer to prove that what ever the mod it caused damage that would allow them to refuse to warranty something...

example...you have axle back exhaust but your water pump starts leaking...we all know that a water pump is not and will not be afected by a axle back muffler..they cant and should not even try to void that work.

steve
 
I think Steve is right. That said, if you change the ECU program and the motor suffers internal damage that could have resulted from lean or rich condition or over rev, they could claim the tune is the cause. Since a cold air, larger MAF, or headers could require a tune to get the air/fuel correct they could be regarded in the same way. I doubt that there would be any significant air/fuel change from any Cat back exhaust changes so it probably wouldn't effect the ECU or considered by a dealer checking on a warrantee claim.

Steve mentioned that the newer ECU's have this record capability that can provide evidence of after market changes that effect the ECU operation. I'm no expert on how they do that, but in the case of a serious engine issue you can bet they will be checking everything. Be prepared to show that all required service operations were performed to spec and on time. I think that dealers have some discretion in what they determine caused an issue. At least they used to. The new electronics have allowed the manufacturers to really tighten up on warrantee claims where mods are concerned.

Mike
 
Wow, thanks guys for the quick response and good advice. I can't believe those mechanics at the dealership told me that erroneous information, but as the article in LateApex's link says, those guys may actually believe that and not be aware of the Magnuson-Moss Warranty Act. I'm going to drop my car off tomorrow morning and have the Kooks axleback installed. Thanks everyone.

Quick side question: The guy at the exhaust shop told me that it would probably be best to leave the restrictor plates in because the exhaust system needs to have back flow/pressure and that's provided by those restrictor plates. He said that without the restrictor plates, the exhaust would have a lot of that popping sound. His advice was to leave the plates in and use the Kooks axleback. What do you guys think?..

Thanks in advance,

Brian
 
Brian, I never heard about the system needing back pressure? Many people have taken them out without any problem what-so-ever. In fact Ford recommends taking them out for a better sounding experience with the Track Key idle.

I have vids posted here of my car without the exhaust discs and also vids of the sound the Boss makes with different size discs. It was a project I started when I first got my Boss and did not like the completely open sound (yes lots of popping and Jake brake sound) or the small factory discs.

https://trackmustangsonline.com/boss-302-technical-forum/after-market-discs/

The way Ford made the exhaust system is great, with simple different sized discs you can personalize the sound to your liking.
 
catalyst said:
Quick side question: The guy at the exhaust shop told me that it would probably be best to leave the restrictor plates in because the exhaust system needs to have back flow/pressure and that's provided by those restrictor plates. He said that without the restrictor plates, the exhaust would have a lot of that popping sound. His advice was to leave the plates in and use the Kooks axleback. What do you guys think?..

Thanks in advance,

Brian
I think what the guy is referring to is where do you want your sound from but he has it backwards. When you open up the back, which is the path of least resistance, you'll get less flow out of the side pipes. That's why there are stock GT mufflers on our cars, which have more back pressure compared to the GT500 mufflers which I use, is so you get more flow out the side pipes. When you open up the back you'll get less flow and sound out of the side pipes. That said many of us don't like the jake brake sound out of the side pipes wide open so we use different sized restrictor plates. The sweet thing is you can tune the sound to your liking by using different size holes. The most popular size is 3/4". I have 1/2", 3/4" and 7/8" and use the 7/8 with my GT500 mufflers. I've been thinking of going back to the 3/4" mostly because it's a touch loud on the freeway. But it sounds terrific driving around town. ;D
 
Wow, those 7/8s sound really nice. Forgive me for asking a dumb question, but opening up the restrictor plates would increase the sound from the side exhaust, especially if you're using aftermarket mufflers, right?

I might be ordering a 3/4 and 7/8 from 2012YellowBoss if that's ok. I want to hear how the Boss sounds with the Kooks axleback on it first. Are they still $27 + $18 for each additional set? I'm in NC. Thanks,

Brian
 
catalyst said:
Wow, those 7/8s sound really nice. Forgive me for asking a dumb question, but opening up the restrictor plates would increase the sound from the side exhaust, especially if you're using aftermarket mufflers, right?

There are no dumb questions, we all need to learn and I have learned a ton from the guys on the forum. Opening up the side pipes increases the sound, so you are correct. As far more sound from the side pipes with aftermarket mufflers I doubt there is a difference then if you retained the factory mufflers. The side pipes as far as I know do not flow much exhaust and were added purely for sound. So they will have their unique sound and you will get a different sound in the back with your after market mufflers.
catalyst said:
I might be ordering a 3/4 and 7/8 from 2012YellowBoss if that's ok. I want to hear how the Boss sounds with the Kooks axleback on it first. Are they still $27 + $18 for each additional set? I'm in NC.

That is correct, if you decide you want them just drop me a PM here or email me at my address in my sig below.
 
IMO You should remove the restricter plates before you buy new mufflers. You will not make any more power but the tone and sound is beautiful. No drone either! You might find you don't need to spend the money on the Kooks. I agree with the previous post about axel backs not freeing up the airflow. If you want to free the flow, install an H-Pipe with out cats. I don't know if the computer will like that but I bet you'd get: the lounder sound, power, weight loss, and cooler exhaust temps. Needless to say, I've thought about the H-pipe. The car sounds so good with the stock exhaust and the restricters removed, that I've left it as is. Remove your restricters before you do anything. You can do it at home in about 15 minutes.
 
I removed my plates within three days of owning the car and have never looked back. I love the sound, and don't find it droning or entirely too loud. Definitely try it, and know that there are plenty of options to tune that with sized plates and get exactly what you want from the system.

Now axel backs can save you some weight on this car, sure, and a pretty fair amount, too. But that aside, I wouldn't expect a real performance gain - headers and midpipes and tunes are where it's at for exhaust gains. The axel backs are mostly a sound thing.

Still waiting for a reasonably-priced midpipe that, ah...encourages better side-pipe fllow ;D
 

Justin

Save the dawn for your dishes!!!
Just take the plates out. It sounds really good with the trackey. I have GT500 mufflers as well and its all I need. They did an article on a stock GT that they put the side pipes on and ford racing axle back. didnt gain anything in power really. they took out the side plates gained 4-6 hp.

I would strap on the kooks after you decide if the exhuast is to your liking with the restrictor plates out.
 
I talked to Kooks at a show the other day about their BOSS 302 specific headers and Exhaust... $1500-$1800 range NOT Installed... They claimed it would add roughly 25-30HP at the rear wheels, but I have heard this before and all I got was 10HP if that... I think I will stick with STOCK exhaust for now, but once warranty runs out (36K or 3 years thanks to the TrackKey), I might look back into a Kooks Exhaust and Headers.

The more you change on the car the more ammo you are giving Ford for voiding your warranty. That being said, just check with your dealer or call "Ford Racing" and ask them what is allowed and what is not... I can't imagine any exhaust system causing problems, even with the talk of back pressure, I don't think there would be enough there, especially with a custom exhaust that is supposed to make it breath better than the stock to cause any concerns or raise any flags.

Now if you where to put a SuperCharger or Turbo's on, then that is a RED flag...

Exhaust, Throttle body, CAI, shifter... those are all main things that people change on cars, regardless of if its a BOSS or not, and I don't think they would cause any issues with warranty. (just be sure to keep your stock stuff if you can).
 
By law. A dealer can not void a warranty
They can possibly void parts of a warrant such as "drivetrain" but to
Say void a warranty in its entirity is incorrect and just adding
Fuel to the fire called ignorance of the federal
Laws that are and have been in place

Headers and there subsystems by any account might void a exhaust
System from a warranty claim or any form of damage
That it can and did cause.

All that needs to be said is educate yourself with the law
Use common sense and enjoy life
 
catalyst said:
I might be ordering a 3/4 and 7/8 from 2012YellowBoss if that's ok. I want to hear how the Boss sounds with the Kooks axleback on it first. Are they still $27 + $18 for each additional set? I'm in NC. Thanks,

Brian
It's ok and he won't mind. ;)

When you open up the rear mufflers you reduce back pressure and there will be less flow out the side pipes. I've done it and so have others. You get a deeper tone by changing out the mufflers and I never said anything about added HP although that's possible. I was told that opening up the side pipes is good for approximately 3 HP.
 
Since a cold air, larger MAF, or headers could require a tune to get the air/fuel correct they could be regarded in the same way.

Headers can be added to the car and no tune is required as the wideband equipped ECU compensates nicely. In fact, it just over-compensates a little bit and the car runs a point or two richer (safer) than stock. This is especially nice in Track Key mode where the OEM tune is aggressively lean, IMHO.
 
They claimed it would add roughly 25-30HP at the rear wheels, but I have heard this before and all I got was 10HP if that

We're getting 30-35RWHP with the Kook's full system. More importantly, we're getting strong results across the entire RPM range. Our Kook's equipped cars can visibly pull away from an OEM-exhaust car on racetrack straight-aways. If your looking for good, legitimate HP gains, this is a good way to go, although I do realize it is pricey and not for everyone.

Regarding the discussion of the sideplates on whether they're needed for backpressure, performance, etc. Much mis-information. 99% of the function of the sideplates is that you can tailor your exhaust sound/loudness quite inexpensively. One way or the other is not going to make any measureable difference in performance.

For those that may be interested in the Kook's set-up, please consider purchasing them for us - much appreciated.

We just bought a 2013 LS to join our 2012 LS. The 2013 is bone stock at the moment so we will get a baseline dyno and then a dyno run with the full Kook's set-up as another data point. Our headers just shipped from Kooks today, so give me a couple of weeks to get them coated and installed and we'll post more results.
 
168
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more ideas for cheap mods under warranty

1) I removed the side plates, it felt a bit more responsive (ie I could feel a hair bit of some added HP)

2) put gt500 abs for a nice deep sound out of the back for followers, it didnt feel any different except it sounds deeper all around and I love the sound

3) dropped in the KN filter, it felt again a bit more responsive , it possibly adds something there.

4) Trackey : ok no difference in power, but everything FEELS different, more compression/deccelaration, throttle is less modulated ( fine with me), and idle gets very loud when very warm (drive an hour , come back and hearing that thing is awesome)

5) I just put in the 302s Grille BUT SANDED DOWN OPEN the lower right corner from the back that was obstructing the intake so I could get more flow to it: again a bit more response , that cheap ram air is probably worth a few Hps or at least more throttle response its worth it too, feels more responsive yet.

all that, and warranty is fine :)

really unless you RACE your Boss, that's plenty of fun, you dont really need more stuff and once you have found the Torque/Power Sweet spot <- thats pretty important for seat of the pants factor , you will be in Hogs Heaven and your car will feel like a total sports car and not a modern sporty gt highway cruiser.
 

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