So i was at my local car show again today and some guy comes over and we get into a conversation about my G8. I tell him I want to get a tune for it and he told me that now gm won't take the mod's anymore. He said now, before they do anything to your car if something happens, they check the ECM/TCM to see if it was flashed or they flash it or something like that. if something was done, they don't fix the car, regardless of what the problem is or if it was caused by the tune or not. I then told them about Vector's stealth tune. He said, yeah he knows about it and he said they have a way around it. So basically, he said if the ECM/TCM settings have been tampered with, they WILL find out and it will completely void your warranty. I am now scared :(

There is a lot of hogwash going around that GM and the dealers are aggressively seeking out modded cars to "void" warranty on. The truth is look at the sign posted in your dealership that sets the fee for connecting to a computer. They won't do this for free. Also from reliable sources they are only going to review this if there is a failure, in order to determine if a mod was responsible, then they would deny waranty for the failure, but would not void the whole car.

Funny thing is, what if GM actually issues an update and you don't have it done - your ecm is going to come up bogus even if it was never touched.

So i was at my local car show again today and some guy comes over and we get into a conversation about my G8. I tell him I want to get a tune for it and he told me that now gm won't take the mod's anymore. He said now, before they do anything to your car if something happens, they check the ECM/TCM to see if it was flashed or they flash it or something like that. if something was done, they don't fix the car, regardless of what the problem is or if it was caused by the tune or not. I then told them about Vector's stealth tune. He said, yeah he knows about it and he said they have a way around it. So basically, he said if the ECM/TCM settings have been tampered with, they WILL find out and it will completely void your warranty. I am now scared :(

This is false, thats the "doomsday" post people were talking about. GM will NOT pay an extra .25-.4 (including lookup time) an hour labor on every job to check every car, its not going to happen. As far as our stealth tune goes, the ONLY way the dealer has to check for Aftermarket calibrations is the CVN's ours match which makes that pretty much case closed. If something changes we'll adapt the tune but this stuff hasnt changed in years, we arent worried you shouldnt be either :)

Chiefpontiac is right on everything but the update thing, calid.gm.com lists ALL updates if you hit complete history, so as long as you have a valid calibration part # and CVN you are golden. He is 100% correct about not scanning every car and only if there is a failure :)

I took my car to the dealer after my tune for a crank relearn. They did the relearn with no questions asked and no mention of my tune. No mention of my catback or CAI either.

I took my car to the dealer after my tune for a crank relearn. They did the relearn with no questions asked and no mention of my tune. No mention of my catback or CAI either.

that has got to be the most comforting thing i heard all day! lol. Thanks for that. What dealer is this?

All of these things are really based on your relationship with your dealer or your servicing dealer. They want your business, "if they have a brain at all" and are not going to just toss your business out the front door after the sale for this, a good dealer makes as much or more in the back end as the front. Unless that dealer is so short sighted that they are a one sale per person franchise. If that is the case then I guess we will be selling A LOT of GM products in the near future. :slap::)

the ONLY way the dealer has to check for Aftermarket calibrations is the CVN's ours match which makes that pretty much case closed.

Umm..couldn't they tell from some PIDs like RPM, AF, Timing that the numbers aren't stock (assuming your tune ups the rev limiter, changes AirFuel, Timing)? AF/Timing might be hard given there's probably no less than three tables that compute them, but shifting WOT at 6500 would to me be a dead giveaway!

But really it all depends on your dealer and you. Don't take your car in full of VHT and MT slicks and want warranty work on the rear diff..

Most dealers are pretty tolerant of mods, as long as they and you are reasonable (headers don't cause trim to fall off etc..).

My dealer is in the Kansas City area.

Umm..couldn't they tell from some PIDs like RPM, AF, Timing that the numbers aren't stock (assuming your tune ups the rev limiter, changes AirFuel, Timing)? AF/Timing might be hard given there's probably no less than three tables that compute them, but shifting WOT at 6500 would to me be a dead giveaway!

But really it all depends on your dealer and you. Don't take your car in full of VHT and MT slicks and want warranty work on the rear diff..

Most dealers are pretty tolerant of mods, as long as they and you are reasonable (headers don't cause trim to fall off etc..).

Not exactly, there is no timing should be X degrees per RPM per load ect in the service manual same with A/F. The rev limiter is only 200 RPM higher and I doubt anyone would notice that. Personally I'd be more worried about why a dealer tech was beating on your car ;) The procedure used to check for aftermarket calibrations is to check the CVN, GM wont pay for digging any deeper than that and techs want the most amount of money for the least amount of work.

Bottom line really is the relationship you have with your dealer, keep it a good one!

Ah ok, so bottom line is: tune isn't that radical to draw undue attention (I'd want to know too why they were redlining my car), and realistically most techs have enough to do without sniffing around PCMs.

Ah ok, so bottom line is: tune isn't that radical to draw undue attention (I'd want to know too why they were redlining my car), and realistically most techs have enough to do without sniffing around PCMs.

Exactly, the only "sniffing" GM will pay for or explain how to do is CVN's which we've taken care of :)

Ever heard of this?

Magnuson-Moss Act

It's a federal law. A warranty CAN'T be voided unless they can prove the modification caused the issue. Look it up, it is a modders best friend.

Ever heard of this?

Magnuson-Moss Act

It's a federal law. A warranty CAN'T be voided unless they can prove the modification caused the issue. Look it up, it is a modders best friend.

I'm sure most of us have heard of it but most of us don't want to spend the money on a lawyer and take the issue to court. GM knows this.

GM knows this.

And if a dealer says, no its not covered, what can you do then? Try another dealership...that's about it. You can complain, but you really can't force them to do it (at least not without a lawyer ($$$)).

They don't VOID your warranty, just deny your claim. Its highly variable...one could say, well your intake and headers increase power over stock and that's basis for the Diff/Transmission failing--too much power sorry. I know in my old GTP the tranny's top hp rating was what the engine produced--5 lb/ft more and GM can say your mods exceed specs..no claim sorry.

Simple bolt-ons usually ok if you have good relationship, more than that forget it--plus expensive repairs require GM rep approval (outside the dealership) and they seem to be a little more saavy when it comes to spotting mods etc.