Mercedes-Benz X-Class Diesel Tuning & Servicing
The Mercedes-Benz X-Class is one of the more unusual utes on Australian roads: a Mercedes badge and three-pointed star sitting on top of a Nissan Navara D23 platform. That mix is exactly what makes it interesting to work on. The Navara underpinnings mean a proven dual-cab chassis and a 3,500kg braked towing capacity, while the Mercedes powertrains, electronics and emissions hardware bring their own character and their own quirks. At Willy’s Workshop we treat the X-Class as what it is: a European-badged diesel ute that rewards the right tune and the right maintenance, and punishes neglect.
Two diesels were sold here. The X250d runs a 2.3-litre Renault-sourced twin-turbo four-cylinder producing 140kW and 450Nm, paired with a seven-speed automatic. The flagship X350d steps up to the Mercedes 3.0-litre OM642 V6 making 190kW and 550Nm, backed by the 7G-Tronic transmission and permanent 4MATIC all-wheel drive. Both are fitted with a DPF and AdBlue (SCR) emissions systems, and both respond very differently to tuning, so we build each calibration around the specific engine, gearbox and how the vehicle is actually used.
Whether you tow a van across the Bruce Highway, run a tray for work, or just want crisper throttle response and better fuel economy, we tune and service X-Class utes in-house at our Oxley (Brisbane) and Warana (Sunshine Coast) workshops. Every performance calibration is developed against the factory ECU and verified on the dyno, never a generic flash loaded blind.
Mercedes-Benz X-Class diesel engines we tune
Your X-Class's tune potential
Pick your engine to see typical gains from a Willys Workshop tune.
Indicative gains on a stock vehicle, measured on a dyno at the engine (crank) — wheel power reads lower (typically 15–20% on a 4WD). Actual results vary with vehicle condition, fuel quality and modifications.
Indicative rear-wheel (dyno) figures with switchable maps, emissions intact. Actual results vary with vehicle condition, fuel quality and modifications.
Why choose Willy’s for your Mercedes-Benz X-Class
Performance Tuning
Custom, dyno-verified ECU tuning built specifically for the X250d and X350d
- Custom ECU calibration developed on our dyno for your exact engine and gearbox, X250d four-cylinder or X350d OM642 V6, not an off-the-shelf file
- Real, measurable gains in power, torque and throttle response, with smoother in-gear pull for towing up to the X-Class’s 3,500kg braked rating
- Transmission tuning to match the seven-speed auto / 7G-Tronic to the new torque curve for cleaner shifts and better drivability
- Calibrations focused on safe, sustainable outputs that respect EGTs, the twin-turbo (X250d) or single-turbo V6 (X350d) hardware, and long-term reliability
Servicing & Repair
Full mechanical servicing and diesel repair for X-Class utes, with European diesel expertise
- Logbook-style servicing, oil and filter changes using correct Mercedes-spec lubricants, and AdBlue (SCR) system top-ups and diagnostics
- DPF diagnosis, cleaning and regeneration for utes used on short runs that never reach regen temperature, plus underlying cause investigation
- EGR system service and intake decarbonisation to address the soot-and-oil build-up that seizes swirl flaps and linkages on these engines
- OM642 V6 specialist work including oil cooler seal leaks, turbo boost actuator faults, timing chain inspection and full diagnostic scanning
Why drivers trust Willy’s Workshop

Mercedes-Benz X-Class diesel FAQs
How much does it cost to tune a Mercedes X-Class, and is it worth it?
Will tuning my X-Class void my Mercedes-Benz warranty?
Can you delete or modify the DPF, EGR or AdBlue system, and is that legal?
What sort of power and torque gains can I expect?
Which X-Class engines and model years do you work on?
How do I book, and how long does the work take?
Book your Mercedes-Benz X-Class in
We tune and service across South-East Queensland — choose the workshop nearest you.

