qtc

any tunes that doesnt void warranty?

AMG_FVR

Nope, Unfortunately all tunes will void powertrain warranty.

qtc

even if i flash it ?

5Zigen18

If there was a powertrain related failure and the technicians really want to dig into the issue, they can pull the ECU and logs to see.

Have a good relation with your SA as that may help but at the end of the day, if you go for a tune be prepared.

AMG_FVR

Yes, a flash is a tune, therefore warranty will be voided.

subzero05

Dinan is in the process of releasing some piggy back units that will carry a 4yr/50k warranty on them which will include consequential damages. Its the same warranty as they are known for on the BMW side. They are not out yet, but apparently in beta testing. They would be your best bet

MASSC450

Especially if you reflash the ECU...

You're less likely to get caught with a tune if it's a piggy-back. The Dinantronics Sport piggy-back unit for my C450 gives a nice safe 4 psig increase max.