Kalaika

Hello all,
I was wondering with the addition of a RENNtech ECU upgrade, would it void my Mercedes warranty? How would the dealership know if it was removed before service? Thoughts?

Thanks

PeterUbers

I pose this question alternatively:

Are you willing to pay out of pocket for any drivetrain issues that are not covered by the warranty if the dealer states they found your tune?

fabbrisd1

The RennTech ECU upgrade/mod does nullify MB warranty coverage on the ECU - but does not affect MB warranty on drivetrain or any other component - there are a good number of MB dealers in Metro area that install RennTech mods (as RennTech dealers so-to-speak)..

No reason to "hide" the mod - and frankly best to tell a dealer upfront you have the mod so they don't accidentally run a MB ECU update over the RennTech program.. usually the RennTech ECU program is "locked" sortof to help prevent that ..

fletino

it depends on many variables, here in europe you can get brabus ecu upgrade via MB dealer, it's kinda more expensive than similar tune via tuning companies but with brabus ecu kit you'll get an extended warranty from the dealer on the whole power/drivetrain (up to 5 years) for free, so if you do the math it's almost as expensive as an extended MB warranty. But any other ecu reflash from someone else will always void the whole warranty. I personaly have came across many situations when something went wrong and owner had to buy a new engine without any participation from the dealer or importer. So I'd not do any ecu reflash except the official brabus one. The machanic will always see what has been done to the ecu when he plugs in his sofisticated diagnostic tools, always. Those times when it was possible to delete the ecu memory without any tracking records are over.

PeterUbers

What facts support this statement?

Dealers that mod with renntech tunes warrant future claims at their discretion and Benz will not warrant those claims.

Before this OP tunes anything he should get the facts from his dealership and can call Mbusa directly to ask

Tobias at Amg released a position on Amg tuned cars -- it is not supported by the Amg-Benz corporation or the warranty... This is a fact

Your post from a little bit ago:

"Glad you guys met and became friends.

A ECU tune on a GL550 will not "void" a warranty per se - however, since the ECU box has to have a small hole drilled into it to release/open for access - "technically" the warranty on the ECU itself is "voided" since it is "technically" a tampered part.

Now part to the matter - since you guys now have the Pole for your Audi".

The issue with a "tune" has to do with adding performance - without setting off CEL for other parts of the system.

Rentech is the most oft named Mercedes "tuner" - and you can visit their website for details regarding your specific rig.

There are also a few Mercedes dealers - who have also become RennTech dealers - so that dealer can sell + install the tune - RennTech also has other independent tuner/retail shops who also are RennTech "dealers" for the tune + install.

RennTech, thru a Renntech dealer - will "guarentee" that their tune - if selected to match to the original vehicle equipment - will be usable and not trigger CEL/limp-home etc.

Any guarentee like that - must be confirmed specifically both with the company supplying the tune and the installer.

Sure - you can see posts - any brand forum - and almost any "tuning company" - where someone(s) say - "installed easy - awesome performance - no problems".

The fact is - what you DON'T see are those that have had problems with their tune.

I had one CLS550 customer - great guy - tuning company out of Texas I had recommended before successfully to other customers. Had my guys pull the ECU - ship it off - get it back - and do the righteous install - long story short - 3 or 4 reflashes later - always some gawdang CEL's and worse - the tuning company even "fried" the ECU on their last flash - they bellied up for replacement ECU - after a whole tale of woe - then we turned back to RennTech - and for that customer - was happy for 3 months and I stepped him up to a G63 - story ends well.

The point is - "most" Mercedes dealers won't step into it - and when you choose to step into a tune - MAKE SURE - you have "clear" understanding on how you will be protected on both "No CEL's - right" and "what if this gets fracked up"..

Keep the beat !"

fabbrisd1

Sure... my post was accurate...and in that case the ECU tuning company reimbursed the cost for new ECU ($600 my MB cost)... and since switching to RennTech exclusively my customers have had zero issues... and no other component/warranty issues on any other systems... all good..really....

roychimac

Never
Ever
Tell your dealer ****.

fabbrisd1

Don't know what you think you're "hiding" - since the Star/cloud recognizes the modded tune as non-OE - tech needs to hit "disregard"/proceed"

yxc145

Last week, a warning light "coolant level low" came on. I stopped in a near by Mercedes dealer and asked them to help topping it off. 15 minutes later. A technician came back with the car and told me next time I take the car in the dealer, I should probably take the tune off. (I have a Vivid Racing piggyback tune). He said he tunes his cars and is cool with it, but not the dealers.

Kalaika

Thanks everyone. I think i know which route I will take.

Nyce007

Does anyone have a dyno chart showing the hp and tq compared to stock? Thinking of getting the Renntch ECU upgrade.