Just bought a new 2010 Silverado LTZ.

I have Onstar and everything, whats the deal with getting a tune...be it hand held or mail order or other.

I am not looking to void the warranty is why I ask.

Is OnStar gonna know I have something done? My last truck didn't have OnStar or anything...so this is kind of new to me. I am not new to tunning by any means...but the diagnostic connection OnStar has is new.

 

i wouldnt think they would be able to tell...

 

On star doesn't know anything about your tune. Can only access OBD2 diagnostic data. Your best bet is to get a custom tune on another PCM from one of the mail order guys and keep your OEM PCM to swap back in for trips to the dealer.

 

can't do that anymore... ^ ^ ^

other data is stored in the ecm's now, one such item being mileage... and if it doesn't match the odometer, bingo! they gotcha... they know it's been swapped out...


but, like was mentioned... onstar can't tell anything about the tune parameters... all they know is if a trouble code is thrown and the CEL comes on....

and as for a dealer knowing anything, if you use the diablosport predator, or better yet - the Trinity - you can restore the original stock GM programming back to the ecm before you take it in for any dealer service work, and they are none the wiser... there are no traces left that anything has ever been changed in the ecm.... so, no worries...

 

Ok, so is this just in the Gas PCM's? This is the first time I have ever heard of the odometer being stored in the PCM. It has always been in the cluster ONLY. I know in the new Diesel PCMs, they can tell every time the PCMs has been flashed, so they will know if a the tune as been changed and then changed back...

 

In that same case, using EFI Live or HP Tuners, when you save and downlaod your stock tune, you could reinstall it right before you head to the dealer.

 

I already contacted Mike on GMTC for questions about the trinity. Mostly about TCM support.

I had a mail order for my last truck, But the trinity is a pretty cool piece of kit.

 

this is something they started doing for 2010+ ECM's... the new 2010+ camaro's have it as well...

the diesel ecm's are a different scenario, and they've been doing it for 2-3 years... but that info is unchanged/undetectable when using a diablosport product as well...

 

You have any info on TCM support for 2010 trucks yet...the 6 speed is 1 million times better than the 4L60E ever was, but it still could stand a little tweaking.

I think riding myself of the DoD would make a huge difference though.

 

GM has had mileage logging for a while in the E38, much like they have reflash history in there too (though not as intricate as the LMM). But, they never seem to enable the ability to read any of this data with the Tech II.