Tune or not to tune?
CF Senior Member
Joined: Feb 2006
Posts: 23,313
Likes: 25
From: Tucson Arizona
IMO and from my experience any alteration of a vehicle from its' stock configuration opens the door for the dealership/GM to deny warranty service for anything even remotely related to the specific modification.
My local dealership aggressively denies warranty repairs on modified cars. I may not like it but I understand GM's position. I feel if you modify your car you have to be prepared to suffer the consequences of losing portions of your warranty.
It's easy for someone to say a tune will not void a warranty or the dealership/GM has to prove a modification caused a problem before they can deny warranty service but for all practical purposes, trying to invoke the Moss-Magnusson Warranty Act and fighting GM would be an exercise in futility.
If a shop says a tune or a certain modification will not void your factory warranty, see if they're willing (in both their corporate and personal capacities) to sign a contract that would obligate them financially to pay for any denied warranty repairs and to pay the expense of hiring counsel to fight General Motors, based on a dealership/GM decision to deny warranty service due to that specific tune or modification (and also to pay for a comparable rental car for all the years it will likely be in litigation).
I've had a shop tell me that a certain problem should still be covered under warranty despite a modification being made but the reality was the dealership still denied warranty service.
My local dealership aggressively denies warranty repairs on modified cars. I may not like it but I understand GM's position. I feel if you modify your car you have to be prepared to suffer the consequences of losing portions of your warranty.
It's easy for someone to say a tune will not void a warranty or the dealership/GM has to prove a modification caused a problem before they can deny warranty service but for all practical purposes, trying to invoke the Moss-Magnusson Warranty Act and fighting GM would be an exercise in futility.
If a shop says a tune or a certain modification will not void your factory warranty, see if they're willing (in both their corporate and personal capacities) to sign a contract that would obligate them financially to pay for any denied warranty repairs and to pay the expense of hiring counsel to fight General Motors, based on a dealership/GM decision to deny warranty service due to that specific tune or modification (and also to pay for a comparable rental car for all the years it will likely be in litigation).
I've had a shop tell me that a certain problem should still be covered under warranty despite a modification being made but the reality was the dealership still denied warranty service.
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
IMO and from my experience any alteration of a vehicle from its' stock configuration opens the door for the dealership/GM to deny warranty service for anything even remotely related to the specific modification.
My local dealership aggressively denies warranty repairs on modified cars. I may not like it but I understand GM's position. I feel if you modify your car you have to be prepared to suffer the consequences of losing portions of your warranty.
It's easy for someone to say a tune will not void a warranty or the dealership/GM has to prove a modification caused a problem before they can deny warranty service but for all practical purposes, trying to invoke the Moss-Magnusson Warranty Act and fighting GM would be an exercise in futility.
If a shop says a tune or a certain modification will not void your factory warranty, see if they're willing (in both their corporate and personal capacities) to sign a contract that would obligate them financially to pay for any denied warranty repairs and to pay the expense of hiring counsel to fight General Motors, based on a dealership/GM decision to deny warranty service due to that specific tune or modification (and also to pay for a comparable rental car for all the years it will likely be in litigation).
I've had a shop tell me that a certain problem should still be covered under warranty despite a modification being made but the reality was the dealership still denied warranty service.
My local dealership aggressively denies warranty repairs on modified cars. I may not like it but I understand GM's position. I feel if you modify your car you have to be prepared to suffer the consequences of losing portions of your warranty.
It's easy for someone to say a tune will not void a warranty or the dealership/GM has to prove a modification caused a problem before they can deny warranty service but for all practical purposes, trying to invoke the Moss-Magnusson Warranty Act and fighting GM would be an exercise in futility.
If a shop says a tune or a certain modification will not void your factory warranty, see if they're willing (in both their corporate and personal capacities) to sign a contract that would obligate them financially to pay for any denied warranty repairs and to pay the expense of hiring counsel to fight General Motors, based on a dealership/GM decision to deny warranty service due to that specific tune or modification (and also to pay for a comparable rental car for all the years it will likely be in litigation).
I've had a shop tell me that a certain problem should still be covered under warranty despite a modification being made but the reality was the dealership still denied warranty service.
But, on another forum, complete with hi po lawyers who wanted to mod their cars, they said even with their "in-house" legal representation, it is a difficult road to fight against a dealership or GM. And that is despite Moss-Magnuson which says no damage can be attributed merely to the addition of a modification; it must be proven.
Remember: at 250-$400 per hour, even if you're doing it for free (lost opportunity cost to make money), a lawyer is not a cheap item.
Wayne is right and wrong on this issue, but he's more "right-er" than "wrong-er".
Former Vendor
Joined: May 2005
Posts: 3,749
Likes: 4
From: Valencia Ca
Here's a tune on a bone stock , M6 coupe. Owner was adamant about not adding any mods and we did the tune.
Gains were across the board and at a few points under the curve there was as much as a 23 ft gain and like hp.
Stock - 347 RWHP - 345 RWT
Tuned -365 RWHP - 365 RWT
So the moral of the story - if you aren't adding more mods get the tune and be happy.
Gains were across the board and at a few points under the curve there was as much as a 23 ft gain and like hp.
Stock - 347 RWHP - 345 RWT
Tuned -365 RWHP - 365 RWT
So the moral of the story - if you aren't adding more mods get the tune and be happy.
Team Owner
Joined: Jul 2004
Posts: 24,652
Likes: 298
From: NJ
St. Jude Donor '05-'08
Here's a tune on a bone stock , M6 coupe. Owner was adamant about not adding any mods and we did the tune.
Gains were across the board and at a few points under the curve there was as much as a 23 ft gain and like hp.
Stock - 347 RWHP - 345 RWT
Tuned -365 RWHP - 365 RWT
So the moral of the story - if you aren't adding more mods get the tune and be happy.
Gains were across the board and at a few points under the curve there was as much as a 23 ft gain and like hp.
Stock - 347 RWHP - 345 RWT
Tuned -365 RWHP - 365 RWT
So the moral of the story - if you aren't adding more mods get the tune and be happy.
Safety Car
Joined: May 2005
Posts: 3,990
Likes: 1
From: Corpus Christi Texas
I was told by the first tuner who tuned my car that I could add such things as headers without a re-tune. If I added a cam for example, a retune then would be necessary. I did add headers and sure enough, a nice gain up .3 and 3 mph in the 1/8th alone, no re-tune. Later had rockers added and then had it retuned on a dyno by a different business. There were no hp/tq gains from the new one, he just fine tuned what I already had. Just my experience.
Melting Slicks
Joined: Sep 2000
Posts: 2,053
Likes: 0
From: Kennesaw Georgia
Warranties have been voided due to tuning !!!It really depends on your dealer... if it's an engine issue !!!
I'm not sure if GM can detect a change if your PCM has been "flashed" and then returned to stock. I am sure Porsche can detect any PCM mods... even if removed.
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