| Manufacturer | Weistec |
| Transmission Family | VGS3-FDCT (8G-Tronic) |
| Tuning Method | Cypher Pro Dealer |
| Module Type | TCU |
| year | make | model | trim | engine |
|---|---|---|---|---|
| 2025 | Mercedes-Benz | GLB35 AMG | Base (X247) | Turbocharged 2L I4 (M260) |
| 2025 | Mercedes-Benz | A250e | Base (W177) | Turbocharged 1.3L I4 (M282) |
| 2024 | Mercedes-Benz | GLB35 AMG | Base (X247) | Turbocharged 2L I4 (M260) |
| 2024 | Mercedes-Benz | CLA250e | Coupe (C118) | Turbocharged 1.3L I4 (M282) |
| 2024 | Mercedes-Benz | B250e | Base (W247) | Turbocharged 1.3L I4 (M282) |
| 2024 | Mercedes-Benz | A45 AMG | Hatchback (W177) | Turbocharged 2L I4 (M139) |
| See more | ||||
Product Description
The 8G-DCT is Mercedes' successor to the 7G-DCT in its compact-car lineup, and it's a real step forward: lighter and more compact than the unit it replaced, while adding an eighth ratio. It's found across the current A-Class, B-Class, CLA, CLA Shooting Brake, GLA, and GLB. Like its predecessor it's a wet dual-clutch design suited to the transverse-engine platform these cars share, valued for combining manual-like shift response with automatic-style ease of use.
Weistec's TCU tune recalibrates the factory 8G-DCT software, executed with the same rigor as Mercedes' own calibration work and without compromising the transmission's built-in protections. Already refined engineering, brought to another level.
How Do You Get Your Mercedes-Benz 8G DCT TCU Tune 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.
Fitment not confirmed
This part is not confirmed to fit your selected vehicle.

