2014+ Engine & Transmission Tuning

[dgrinnell]

At the time it was just an ECM tune but I think hes waiting on the TCM now

[dredd]

I would do this if I thought the Dealer wouldn't know like Moto said about the Black Bear. I asked my service writer about tune and he said dealership would definitely use it to void warranty work.

[iCryWheniGoPoop]

That's how all dynos work. 3rd gear pulls from 15-20 mph. In the "power band". You wouldn't see much of a difference down low on paper but real time driving it's day and night. The truck holds gears much better and never downshifts when going up hills. I put it to some tests yesterday and was very impressed with the gains and trans shift points. Sent from my iPhone using Tapatalk

Actually... You can read lower on the Dyno, it's just not a typical practice because most people just want peak numbers. A Diesel engine is well past halfway through RPMs at 2500. I can Dyno you from a dead stop if you like.

 

Also, actual gear or gear number is irreverent, ideally you want the gear closest to a 1-1 ratio in the transmission for the most accurate reading. The steeper the gear offset is, the more power it robs, that goes for rear ends as well.

Edited February 22, 2014 by iCryWheniGoPoop

[iCryWheniGoPoop]

Ok, there seems to be a little confusion and a lot of misinformation passed around the internet that WILL eventually bite one of us in the butt when they go in for a warranty after they get their truck tuned. I just want to lay some of this information out on the table so that when we get that bill for a failed lifter or a transmission replacement, we already have our checkbooks out and pen in hand.

 

Is there a Flash Counter? NO! Well kind of. its actually more complicated than that but it roughly sums it up. It is actually more of a Flash History Log using what GM calls CVN's or (Calibration Verification Numbers) For those of you that are Techie it is a Checksum Value which is the value of your calibration.

 

This is VERY Simplified -

Timing table = 10

Fuel table = 10

Trans shift table = 5

Trans pressure table = 5

rpm limit table = 2

speed limiter table = 2

 

This would make your stock CVN = 34. Now if you change anything in your tune it will effect the CVN value and the dealer will see that it is not what came factory and bam- bye bye 5/100k

 

Will they catch it if we change it back to stock? YES

They actually log ANY CVN CHANGES which they can access at any time with the Tech 2 or 3. The kicker is, it only logs CHANGES to the CVN value. I'm not 100% sure for 2014 on how long the history is but from past ECU's it is at least a 10 CVN change history. Since the ECU is only logging CVN changes, that keeps us from being able to flash the stock tune back in 10 times to wipe out the history.

 

What happens when the dealer flashes in a new Calibration like when we had the exhaust overheat recall? This is actually logged in the CVN history but GM is fully aware of what they put in each vehicle and is all tracked through our VIN #'s.

 

The Dealer CANNOT see what was changed in the calibration, they can only see that it was changed and that is all they need. If the ECU is sent to GM engineering, they can tell you what was changed.

 

What is getting me is that there are Tuners out there saying that this is all a bunch of BS and that GM will never know. The guys at both the major software tuning companies know this and make it public - they have nothing to gain by this except for loss in sales from people scared to tune now, and that is where I got most all of this information with a little help of a couple Techs with Tech 2's. In 2008 this technology was alive and kicking in the Duramax platform, in 2010 it was in the Camaro/Vette. 2014 its in our brand new truck design that we are so eager to tune because honestly, there is a lot being held back on this new DI motor.

 

I know there will be some Magnuson-Moss Warranty Act posts... just remember, it clearly states in our warranty verbiage that any changes/modifications to the ECU will void warranty period and... If you feel you are in the right, it is little ole you against GM, so think long and hard before plunging into that ECU.

 

Take this information for what it is but IF your truck starts using oil, engine starts rattling, transmission starts slipping and you have a tune... The first thing you will think is "I hope that iCryWheniGoPoop guy was full of crap".

 

Steve

 

 

Edited February 23, 2014 by iCryWheniGoPoop

[Ulukslo]

We tuned my uncles and he went back n had all warranty work done at local dealership and they said nothing. I know GM will void your warranty but it also depends on your relationship with the dealer your using. Living in a small town with buddies wrkn at dealership helps! I know of several techs installing aftermarket camshafts under factory warranty when a lifter has scarred camshaft. They have also installed torque convertors and other things such as heads or different things. What it ammounts to is whether your service guy is a dick or not. I understand GM can force them to download file and your screwed but I think it may be able to be gotten by maybe 1 time but if its a major failure like an engine then its not gonna be good news prolly!! Ive already turned off my speedo limiter but not tuned yet. But Im prolly gonna take the plunge!! I also think that the guys doing big tires and lifts are voiding their warranty if the service manager is a dick. If I did wheels tires and lift I would deff tune ECM TCM because trans would prolly end up living longer in my opinion.

Give me your opinion on the lifted trucks iCRY

[iCryWheniGoPoop]

With GM... Dealership has no say. It is all up to corporate engineering because when they get your CvN info, it is usually because engineering requested it.

[iCryWheniGoPoop]

Let me rephrase that, they have no say IF the CVN log is requested. My dealership will do all they can for me otherwise

[CAtaylor]

Mine came from the dealer just like it sets. If the dealership is going to do this they should go ahead and do all of the tuning corrections for you and install the appropriate gears. I am changing the gears on mine to correct this and will more than likely take a hit for it if something comes up but i feel for the longevity of the truck it is required. Heck the speedometer wasn't even corrected when I got it and I am still debating on fixing that.

[Mutau95]

Maybe I've not searched the right places but I can't seem to find anything online where a Silverado/Sierra truck with a street tune has blown their engine or tranny. Not saying that it won't or hasn't happened but I would imagine the odds would be low. Now I'm not talking about guys who have turbos/superchargers or aftermarket cams. Since these engines gain almost 30 HP and 30+ lb ft of torque with E85 I don't see where a custom street tune will stress these engines much. It seems that people are getting roughly 40 more HP with custom tunes with only bolt-ons.

[Ulukslo]

Maybe I've not searched the right places but I can't seem to find anything online where a Silverado/Sierra truck with a street tune has blown their engine or tranny. Not saying that it won't or hasn't happened but I would imagine the odds would be low. Now I'm not talking about guys who have turbos/superchargers or aftermarket cams. Since these engines gain almost 30 HP and 30+ lb ft of torque with E85 I don't see where a custom street tune will stress these engines much. It seems that people are getting roughly 40 more HP with custom tunes with only bolt-ons.

You are correct but it only takes 5 seconds for a tuner thats not experienced to F up your trans!! Very easily done! I still believe a 6l90 will last longer with a good tune than without!! However you that choosle to tune make it a point to go back later on in life like 100,000 or 80,000 and get shifts firmed up they will loosen up as trans wears. A good clean firm crisp shift cant hurt a thing though!!

[iCryWheniGoPoop]

Maybe I've not searched the right places but I can't seem to find anything online where a Silverado/Sierra truck with a street tune has blown their engine or tranny. Not saying that it won't or hasn't happened but I would imagine the odds would be low. Now I'm not talking about guys who have turbos/superchargers or aftermarket cams. Since these engines gain almost 30 HP and 30+ lb ft of torque with E85 I don't see where a custom street tune will stress these engines much. It seems that people are getting roughly 40 more HP with custom tunes with only bolt-ons.

Sure, I'm not pointing fingers at the cause of a hard part failure, it could just be dumb luck that your engine failed or trans went. The ECM controls so much now, I'm not sure what all they (GM) could blame on a tune. It could very well be that a good tune would increase your engine/trans life . There are a lot of very capable tuners out there that can deliver a better/safer tune than what GM gives us.

Edited February 23, 2014 by iCryWheniGoPoop

[iCryWheniGoPoop]

Give me your opinion on the lifted trucks iCRY

 

You are right, I would probably get the pressure up a bit so that the clutch packs are held a little firmer and shorten the shift overlap between shifts at minimum. GM sets trans line pressures in a narrow window or sweet spot because they try to keep it just high enough that it will handle the advertised tow rating but at the same time they don't want to turn it up any higher than needed because the more pressure the pump has to make, the more parasitic loss there is which in turn uses more fuel/power which makes it less EPA friendly, God Forbid.

[Sooperdave]

This is like the first 6.2L tune post I could find anywhere! LOL Sounds like great results as expected.

[CorvetteOJ]

This is like the first 6.2L tune post I could find anywhere! LOL Sounds like great results as expected.

Yes David, you can take every word I have put in this thread as "straight shootin, honest to goodness fact." I have never been any more impressed with a tune. The fact that he street tunes the trucks doesn't take anything away from the results. i would do it again in a micro-second! Good luck with yours.

 

OJ

[Sooperdave]

PCM's been in the biz for a while. Good people! I'm fortunate to have two great LS engine tuners in the same area so I will be getting either one to do mine. Futral Motorsports and Engine Power Systems. I've got my eye on a Magnaflow exhaust and a K&N CAI before hand though. I just anxiously awaiting my truck!