| Weistec Horsepower | 331 |
| Weistec Torque | 296 |
| Manufacturer | Weistec |
| Street legal in all the US States | No |
| Engine Family | M276 |
| Stock Horsepower | 302 |
| See more | |
| year | make | model | trim | engine |
|---|---|---|---|---|
| 2015 | Mercedes-Benz | ML350 BlueEFFICIENCY | Base (W166) | 3.5L V6 (M276 DE35) |
| 2014 | Mercedes-Benz | ML350 BlueEFFICIENCY | Base (W166) | 3.5L V6 (M276 DE35) |
| 2013 | Mercedes-Benz | ML350 BlueEFFICIENCY | Base (W166) | 3.5L V6 (M276 DE35) |
| 2012 | Mercedes-Benz | ML350 BlueEFFICIENCY | Base (W166) | 3.5L V6 (M276 DE35) |
| 2015 | Mercedes-Benz | GLK350 | 4Matic (X204) | 3.5L V6 (M276 DE35) |
| 2014 | Mercedes-Benz | GLK350 | 4Matic (X204) | 3.5L V6 (M276 DE35) |
| See more | ||||
Product Description
The M276 family also includes a naturally aspirated 3.5-liter variant, badged DE35, that predates and runs alongside the turbocharged 3.0-liter version on its own terms rather than sharing its forced induction. Produced through the mid-2010s for C- and E-Class models, it's a genuinely smooth, high-revving V6 that rewards a calibration built around how it actually breathes rather than around boost, delivering real, linear power without a turbo anywhere in the mix.
Weistec's tune for the DE35 is a software-only recalibration that works with the factory's naturally aspirated hardware, refining fueling and timing across the rev range while leaving the factory's knock protection, thermal management, and OEM diagnostics fully intact. Built to the same OEM-level standard as every Weistec calibration, it's good for a solid, usable gain across the powerband.
How Do You Get Your M276 DE 35 ECU Tune, Naturally Aspirated Tuned?
Follow these steps — this is what your specific vehicle needs and supports.
Choose Your Tune Stage
Core Improvements
Standard with this tuneFree Add Ons
Pick Your Tuning Method

Cypher Plus
Order a Cypher Plus and tune your car yourself from your phone, entirely through the MyFlasher app. Watch how it works.

Mail It In
Remove your ECU or TCU and mail it to us for tuning. Required for some applications.

In Person
Bring your vehicle, or just your ECU/TCU, to our Anaheim, CA headquarters. Call 714-202-0005 or email sales@weistec.com to schedule.

Cypher Pro Dealer
Visit a certified Cypher Pro Dealer near you. Find one with our dealer locator.
Complete The Upgrade
An ECU tune alone won't remove all factory limits or fix how power reaches the ground. Add these to round out the upgrade with no limitations.
Read the full CPC & TCU breakdown →
What is a CPC module?
The CPC (Central Powertrain Control) is a separate control unit that manages things like the active exhaust valves, radiator fan, intercooler pumps, and speed limiter. On many newer Mercedes-Benz vehicles, it also houses torque limiters that can hold back an ECU tune from reaching its full potential.
What is a TCU tune?
A TCU (transmission control unit) tune delivers faster, firmer shifts with higher line pressure, reducing clutch slip and increasing the transmission's torque capacity. It's a worthwhile upgrade on its own, or paired with an ECU tune for a fully sorted powertrain.
Good to Know
- This is a reflash of your original module, not a stand-alone unit.
- Power gains vary by vehicle, modifications, fuel, and operating conditions (ambient temperature, altitude, etc.).
- New or upgraded spark plugs are always recommended when tuning.
- Product may not be emissions compliant. Check local laws prior to installation.
- Always use a battery charger during programming.

