Mercedes-Benz Diesel

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.

Engines We Tune

Mercedes-Benz X-Class diesel engines we tune

X250d 2.3L twin-turbo 4-cylinder (Renault-based, 7-speed auto)

140 kW / 450 Nm

Renault-sourced twin-turbo four; responds well to custom tuning but shares the platform’s DPF/AdBlue maintenance needs

X350d 3.0L OM642 V6 (7G-Tronic, 4MATIC)

190 kW / 550 Nm

Mercedes OM642 V6 with permanent AWD; strong torque, but watch oil cooler seal leaks, swirl-flap/EGR carbon build-up and timing chain wear

Tuning & Servicing

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

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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

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See all Mercedes-Benz tuning & servicing

The Difference

Why drivers trust Willy’s Workshop

In-house ECU tuning

Custom maps written on your factory ECU — never generic off-the-shelf files

Dyno-verified

Every result measured before & after on our in-house dyno

Dealer-grade tooling

Genuine OEM software and diagnostics, not guesswork

Warranty-conscious

Logbook servicing kept up to date with manufacturer schedules

Two QLD workshops

Oxley (Brisbane) & Warana (Sunshine Coast)

Mercedes-Benz diesel performance tuning & servicing at Willys Workshop

FAQ

Mercedes-Benz X-Class diesel FAQs

How much does it cost to tune a Mercedes X-Class, and is it worth it?

Pricing depends on the engine (X250d four-cylinder versus X350d V6), what you want from the vehicle, and whether you also want transmission tuning. Because every tune is custom and dyno-verified rather than a fixed-price generic file, we provide a quote after discussing how you use the ute. For owners who tow, carry loads or just find the factory throttle response lazy, the gains in usable torque and drivability are very worthwhile. Contact our Oxley or Warana workshop for a quote.

Will tuning my X-Class void my Mercedes-Benz warranty?

If your X-Class is still within the factory warranty period, any modification to the engine calibration can affect warranty cover on related components. We’re upfront about this so you can make an informed decision. Many X-Class owners tune once the vehicle is out of warranty, or accept the trade-off knowingly. We can talk you through exactly what a tune does and does not touch before you commit.

Can you delete or modify the DPF, EGR or AdBlue system, and is that legal?

Removing or disabling factory emissions equipment such as the DPF, EGR or AdBlue/SCR system is not legal for vehicles driven on Australian roads, and we don’t fit illegal deletes for road cars. What we do is keep these systems working properly: diagnosing and repairing DPF blockages, servicing the EGR and intake, and sorting AdBlue sensor and SCR faults so the emissions hardware functions as intended without nagging warning lights.

What sort of power and torque gains can I expect?

Gains vary between the X250d and X350d and depend on your goals and supporting hardware, so we don’t quote a blanket figure. We measure your ute’s baseline on the dyno first, then develop a calibration that lifts power and torque safely while protecting the turbo, exhaust temperatures and driveline. You’ll see the before-and-after numbers from your own vehicle, not a marketing claim.

Which X-Class engines and model years do you work on?

We service and tune both Australian-delivered diesels: the X250d (2.3-litre twin-turbo four-cylinder, 140kW/450Nm) and the X350d (3.0-litre OM642 V6, 190kW/550Nm with 4MATIC). The X-Class was sold here from 2018 until production ended in 2020, and we work on the full range of those build years, including high-kilometre examples needing diagnostic and emissions work.

How do I book, and how long does the work take?

Call or message our Oxley (Brisbane) or Warana (Sunshine Coast) workshop to book. A standard service is typically a same-day job. A custom dyno tune is usually booked for a full day so we can baseline, calibrate and verify the result properly. Diagnostic and repair work such as DPF, EGR or oil cooler jobs is quoted after inspection. We’ll give you a realistic timeframe when you book.

Two Queensland Locations