Remote ECU tune · 6.6L Duramax LML V8 turbo-diesel
A custom Stage 1, 2 or 3 calibration for your Chevrolet Silverado / Sierra 2500HD/3500HD 6.6 Duramax LML, built by hand by a real tuner from your own stock file and datalog, and back with you within three hours of the file arriving. We tune these cars remotely, worldwide: you read and flash with your own HP Tuners interface, and you pay only once the tune is delivered.
Stock vs tuned
From the factory the Chevrolet Silverado / Sierra 2500HD/3500HD 6.6 Duramax LML makes 397 hp and 765 lb-ft (1,037 Nm). A Stage 1 tune typically adds 80–135 hp and 170–243 lb-ft, for around 477–532 hp in total. With bolt-ons and a Stage 2 calibration that grows to +100–160 hp, and a Stage 3 build — upgraded turbo — typically lands at 577–677 hp.
| Stage | Added power | Added torque | Total power | Total torque |
|---|---|---|---|---|
| Stock | — | — | 397 hp | 765 lb-ft (1,037 Nm) |
| Stage 1 | +80–135 hp | +170–243 lb-ft (+230–330 Nm) | 477–532 hp | 935–1,008 lb-ft (1,267–1,367 Nm) |
| Stage 2 | +100–160 hp | +199–280 lb-ft (+270–380 Nm) | 497–557 hp | 964–1,045 lb-ft (1,307–1,417 Nm) |
| Stage 3 | +180–280 hp | +295–413 lb-ft (+400–560 Nm) | 577–677 hp | 1,060–1,178 lb-ft (1,437–1,597 Nm) |
Typical gains from published dyno results; your car will vary with fuel, mods and conditions.
Supported versions
HP Tuners lists 2 Chevrolet Silverado / Sierra 2500HD/3500HD 6.6 Duramax LML entries covering 2011–2016, with 6.6-litre engines, diesel versions included. Interface: MPVI2 or newer.
| Years | Make | Model / engine as HP Tuners lists it | Controller | Credits | Interface |
|---|---|---|---|---|---|
| 2011–2016 | Chevrolet | Silverado 6.6 Duramax (Diesel) (LML) | Engine | 2 | MPVI2/2+/3/4 |
| 2011–2016 | GMC | Sierra 6.6 Duramax (Diesel) (LML) | Engine | 2 | MPVI2/2+/3/4 |
Support data per HP Tuners' supported-vehicle list (June 2026). Check your exact car on HP Tuners' vehicle list before you buy credits.
Stages & prices
One flat price per stage, the same for every car: $250 for Stage 1, $450 for Stage 2 and $650 for Stage 3. Ordering is free and you pay only once the finished tune is delivered. 2 free revisions are included with every order. Gearbox (TCM) shift tuning is included wherever your car's transmission controller can be accessed.
Software only. Every map in the engine ECM is recalibrated for the Chevrolet Silverado / Sierra 2500HD/3500HD 6.6 Duramax LML as it sits today — spark, fuelling, throttle response and limiters — against the datalog you send.
For a Chevrolet Silverado / Sierra 2500HD/3500HD 6.6 Duramax LML with bolt-ons fitted — intake, exhaust, headers or downpipe, and an intercooler where the car has one. The airflow and fuelling are rebuilt around the hardware you actually have.
Stage 3 on the Chevrolet Silverado / Sierra 2500HD/3500HD 6.6 Duramax LML means upgraded turbo. The fuel, spark and boost maps are written from scratch for your exact combination.
Typical gains from published dyno results; your car will vary with fuel, mods and conditions.
Before you order
How it works
FAQ
Typically 80–135 hp and 170–243 lb-ft (230–330 Nm) over the stock 397 hp, for around 477–532 hp in total. Typical gains from published dyno results; your car will vary with fuel, mods and conditions.
An HP Tuners interface (we recommend the MPVI4), the HP Tuners credits needed to license the engine ECM for writing, and your stock file plus a datalog of a drive. You read and flash the car yourself; we build the calibration.
Your custom tune is delivered within three hours of your stock file arriving. Six tuners work three shifts, so a file that lands in the middle of the night is picked up just as fast.
Stage 1 is $250, Stage 2 is $450 and Stage 3 is $650, flat. Ordering is free and you pay only once the finished tune is delivered. 2 free revisions are included with every order.
Stage 3 on the Chevrolet Silverado / Sierra 2500HD/3500HD 6.6 Duramax LML means upgraded turbo. The maps are written from scratch for your build, and typical results are 180–280 hp over stock. Typical gains from published dyno results; your car will vary with fuel, mods and conditions.
