GMC Sierra 1999 - 2007 Engines
Below are the 6 engines we cover for the GMC Sierra 1999 - 2007 — each one links to its own performance page with dyno-tested figures.
- 4.3 V6 200hp · petrol
- 4.8 V8 295hp · petrol
- 5.3 V8 295hp · petrol
- 6.0 V8 360hp · petrol
- 6.6 Duramax 365hp · diesel
- 8,1 V8 330hp · petrol
Selecting the correct engine from the 6 listed for the GMC Sierra 1999 - 2007 matters more than the generation alone — ECU hardware and tuning headroom can vary significantly even between engines of similar size.
Frequently asked questions
Which tuning stages does the GMC Sierra 1999 - 2007 support?
It depends on the specific engine — pick yours below and its performance page will show exactly which stages (Stage 1, and Stage 2 where supported) are available.
How fast can a GMC Sierra 1999 - 2007 file be turned around?
Typically a few hours from upload, tracked live in the member panel once your request is open.
Is ECU remapping safe on the GMC Sierra 1999 - 2007?
Yes, when done within the limits set for that specific engine — which is exactly what our stage options are calibrated to. Every file is worked by someone experienced with that engine family.
How do I identify my exact GMC Sierra 1999 - 2007 engine?
Check the ECU sticker under the hood, or the engine code on your vehicle documents — either one will match against the list below.