Why buy from us ?




We have over 375 resellers worldwide to better serve you

Best aftersale support in the market with 15 employees

All our tuning are made in house and Dyno tested

We offer tuning on more brands and models than any other competitors.

We are #1 tuning shop in North America since 1987! Over 30 000 truck tuned!

Beware of sites that don't list their phone numbers nor provide a physical address. That may indicate a one-man operation and poor (or non-existent) support. Google map is a good resource! Know who you are buying from. If their address is in a residential area be careful. Ask if you get the source code for the software you are buying. If they say no, then you may be in for unexpected charges for bug fixes in the future. 


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LOWEST PRICE GARANTEE. 30 days satisfaction warranty or money back.

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Diesel Spec Inc. is the leader in truck diesel engine ECM tuning technology. With over 30,000 medium and heavy-duty diesel truck tuning performed, Diesel Spec has built its reputation with countless satisfied customers all over the world.


If you are looking to improve fuel economy and/or increase the power of your current engine, we are confident that our expertise can help you achieve these goals. We offer a 30 Day satisfaction money back guarantee on all our tuning.


Diesel Spec has over 375 dealer locations in North America. We are growing with dealers now in Australia, New Zealand, Mexico, France, Austria, Chili and even South Africa. We can serve you, no matter wherever you may be, all around the world.


Diesel Spec specializes in fuel efficiency and performance tuning for owner/operators and fleets alike. Our high performance tuning designed for drag racing and off road competition may require EGR valve delete, DPF delete ( Diesel Particular Filter ) and/or Urea deletion kits. These changes would make for a winning upgrade.


We offer tuning for:

Cummins, Caterpillar, Detroit Diesel, Mercedes, International Maxxforce, Paccar and most agriculture engines.


Established in 1987 and with over 27 years of experience in heavy duty diesel engine, Diesel Spec Inc. is the best choice for all your heavy duty truck engine and performance needs.


Diesel Spec  continue to be innovative, each day, to keep our customers satisfied by offering them the best quality service possible and the latest technologies.

We are specialized in the following engines :

  • Cummins
  • Caterpillar
  • Detroit Diesel
  • Paccar
  • International Navistar
  • Mercedes
  • John Deere