The National Hot Rod Diesel Association - The largest and longest-running diesel motorsport organization in the world.
NHRDA Diesel Drag Racing Classes & Rules
Welcome to the National Hot Rod Diesel Association's official rules and class specifications for the 2025 racing season. All competitors must familiarize themselves with the current rules and regulations.
Important Safety Notice
Rules are subject to change without notice. All safety equipment and certified products cannot be modified, altered, or in any way vary from the as-manufactured condition. It is the responsibility of each participant to ensure that their equipment meets current NHRA/NHRDA standards and is properly maintained.
W9 Requirement for Payouts
A completed W9 form must be submitted to NHRDA for any prize payouts to be processed and sent. Download the form below and submit to NHRDA prior to the event.
Official Documents & Downloads
Download the latest rulebooks and required forms
2025 Drag Racing Class Rulebook
Official class rules, specifications, and safety requirements for all NHRDA drag racing classes.
Download RulebookBurnout Pit Rules & Judging
Competition rules, judging criteria, and class divisions for burnout competitions.
Download RulesW9 Tax Form
Required IRS Form W-9 for prize money distribution. Must be completed and submitted for payouts.
Download W9 FormNHRDA Racing Classes
From professional to sportsman divisions, NHRDA offers classes for every skill level
Professional Classes
Top Diesel
The fastest and quickest diesel trucks in the world. No-holds-barred racing featuring extreme builds.
Pro Mod
Modified diesel trucks with extensive engine work and chassis modifications. Extreme performance builds.
Pro Street
Street-legal diesel trucks with significant modifications. Must maintain street trim appearance.
Hot Rod Semi
Modified semi tractors racing on the drag strip. Exciting big-rig competition showcasing diesel power.
Sportsman & Index Classes
Sportsman
Entry-level class for diesel enthusiasts. Great for beginners and street trucks with basic modifications.
Super Diesel (7.70 Index)
Index class for street-legal diesel trucks. Consistent performance and driver skill are key.
6.70 Index
Faster index class requiring more modifications while maintaining street legality.
Super Street
Competitive street-legal class featuring moderately modified diesel trucks.
Big Rig Bracket
Bracket racing for semi trucks and big rigs. Dial-in format emphasizes driver consistency.
Need More Information?
For complete class specifications, technical rules, safety requirements, and competition procedures, please download the official 2025 NHRDA Drag Racing Class Rulebook above.
Questions? Contact NHRDA at (855) 658-4353 or info@nhrda.com
Ready to Race with NHRDA?
Download the rulebook, review the class specifications, and join us at the next NHRDA event!
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