I have a 2014 E550 4matic and I am also interested in doing the ECU upgrade from Rentech, however I have a few concerns. I am concerned about the transmission and the 4 matic system. Does anyone have the upgrade for any length of time? Has anyone experienced any long term problem? I don't want to shorten the life of my trans or damage the 4matic system. I am worried that the drive-train can't handle the increased power. Lastly, my last question is how does the car drive day to day as a daily driver.

 

These upgrades are all so tempting but these cars are so ridic expensive to repair if u lose that warranty ... That being said id love to drive a tuned tt e550

 

No kidding - if I knew that a Renntech flash would not impact my warranty I would have done it already. As is the E550 is pretty awesome - a flash would turn it into a true monster - call it an AMG-lite!

 

And it would probably end up being faster than any of the NA E63 AMGs. Wouldn't want to line up against a TT 5.5 AMG though...

 

I was wondering if anyone had any information on how the Ren tech ECU upgrade affects the transmission long-term? I am interested in buying this upgrade for my car but I was concerned about longevity of the vehicle. I have a 2014 E550 sedan 4Matic. Any advice would be appreciated.

 

Thats crazy, i just purchased a 2014 E550 Coupe, did the resonator delete with straight pipes and ran a best of 12.48 @ 112.38. i want the tune done but im not sure if there is any difference between the 2012 and the 2014 or is it that your is a sedan?

 

I think the difference might be due to weight. E550 4matic is a heavy ride.