Truck General Rules
Updated: Jan 19
Any owner that is found illegal by tech and knows he is legal may prove himself by
tearing down. When any vehicle is found illegal on cubic inch, the vehicle and owner
will be suspended for 1 year and ten (10) days and will lose his points for the entire
1) Drawbar height or distance from center of rear axle cannot change during the pull.
2) Hitch point to rear axle centerline must be a minimum of 36% of wheelbase for pro
stock and 30% for modified.
3) Primary hitch must be secure to the vehicle frame and rigid in all directions. Hitch
stem may be any length, as long as point of hook is not less than the minimum % rule
of wheel base, maximum distance cannot change during hook.
4) Hitch stem angle must not exceed 25 degrees measured on the stem with angel
finder. Main stem must be straight from point of hook to pivot point (on same plane)
5) Adjuster going to rear end must be attached on center line or lower.
6) Hitch adjuster support (turnbuckle sear) must be vertical.
7) Hitch adjuster must be located no more than 6 inches from point of hook.
8) Hitch height cannot exceed 26 inches from point of hook to ground or track.
9) Hitch cannot pull from rear end.
10) Vehicles must have vertical bumpers at the rearmost point of the vehicle. Bottom
of bumper to be a minimum of 18 inches from the ground. Bumper to extend a
minimum of eight (8) inches vertically. Must be rigid.
11) An area five (5) inches wide and twelve (12) inches high immediately above the
drawbar must be free of all obstruction (including weights, wheelie bars and second
drawbars) for ease of hooking and unhooking.
12) No L-shaped drawbars or trick hitches, which will be enforced by putting a
straight edge from the point of the hook to the center of the pivot point.
13) If body extends more than twelve (12) inches behind point of hook, the open area
must be eighteen (18) inches above the drawbar and 24 inches wide at rear most
point of body.
1) Vehicle must have three (3) round metal loops per drive shaft.
2) 360-degree loop must be a minimum of 3/8-inch aluminum or 5/16-inch steel, 3/4-
inch-wide (or wider) and not more than 2 inches from the shaft in any direction.
3) End loops to be placed no farther than six (6) inches from universal covers, with
third loop in center of shaft.
4) Must use a solid tube (3/8-inch aluminum or 5/16-inch steel) to meet the above
5) If planetary reductions at wheel are used, the following drive shaft shielding
criteria will apply.
a) No cast metals.
b) All remaining drive train, excluding additional manual transmissions, must be
enclosed in 5/16-inch minimum steel or 3/8-inch aluminum, round, inside diameter
not to exceed two (2) inches more than the outside diameter of the largest universal
joint, fastened every six (6) inches or closer, with 3/8 inch or larger bolts, grade #5 or
butt and seam welded and securely mounted to vehicle’s frame. Applies to all
vehicles with exposed drive shaft. No more than 1⁄4 inch of the end of driveline shall be
visible with driveline shielding in place.
c) Drive shafts between engine and transfer case must have solid shielding a
minimum of 3/8-inch aluminum or 5/16-inch steel.
d) Vehicle must have 360-degree metal shield around the universal joints, 3/8-inch
aluminum or 5/16-inch steel, minimum width six (6) inches. Joint should not be visible
from side, top or bottom.
e) May use solid tube (3/8-inch aluminum or 5/16-inch steel) to meet the above
6) No Counter balances permitted in driveline.
7) No cam type rear-ends. All rear ends must be welded or bolted solid to the frame
with a minimum of 3 bolts per side.
NOTE: If a split design is used, mount as in Rule 5b above.
1) All side doors must be on and closed during competition. Vehicle doors must have
a single latch design, allowing the door to be opened from both the inside and the
2) Front and back safety glass or Plexiglas required.
3) Flip-top-body type vehicles and vehicles that do not have two (2) working doors or
less than stock size window openings; must have door glass lowered or removed
while under green flag and must have an escape hatch with a minimum size of 17
inches X 18 inches. Working left hand door RECOMMENDED for safety issues.
4) Vehicles that do not have working doors must carry an onboard fire system with a
minimum of three (3) nozzles located within the driver’s compartment/engine
compartment. And drivers must wear SFI 3.2A5 protective fire suits.
5) May compete without: bumpers, tailgates, van rear doors for greater hook point
6) Truck bodies may be a fiberglass complete body or components.
7) Vehicle box must have a floor or bed cover.
8) Tinted or shaded windows hindering driver’s vision out the front or back will not be
9) Flip-top or funny car type vehicles must have body in lowered position before
vehicle may be moved under its own power.
10) Flip-top bodies must have a safety lock to hold up the body.
11) Body may be raised to start engine and may stay raised while engine is running
as long as vehicle is not in motion.
NOTE: Escape hatch will not be counted as a working door
1) No fuel tanks, fuel pressure gauges, fuel pumps and/or fuel lines are allowed in the
2) If the fuel tank is located behind the driver, a fire barrier is required from the
firewall to the rear of the driver’s seat. (0.060-inch aluminum or steel is an
acceptable fire barrier material.)
3) No radiator, heat exchanger and/or water hoses allowed inside the operator’s
4) If a battery is inside the operator’s compartment, it must be safely enclosed and
1) All weights must be securely attached to vehicle. Loose ballast (sandbags, rocks,
unattached metal, etc.) not allowed.
2) No dual wheels, chains or studded tires allowed. All tires must have rubber or
rubber compound contact between tire and pulling surface.
3) Axle and hub bolt shield required, except where planetary final drives are used.
4) Shield must be at least 0.060 inches thick.
5) Minimum diameter of axle end or hub bolts to be covered on both front and rear
6) Mounting shield cannot be mounted to axle end or hub bolts.
7) A hole may be installed in center of front shield, so a lock can be operated, so long
as hub end or axle bolts are covered.
1) All pulling vehicles must be required to have a steel plate or billet flywheel. The
flywheel must be made of steel with the following mechanical properties: tensile
strength of 60,000 PSI and yield strength of 40,000 PSI. Any aluminum or magnesium
flywheel that meets or exceeds SFI specs will be acceptable. Clutch papers must be on
file in the office and must be produced upon demand. SFI approved—new papers are
due each year.
2) Any truck with engine-driven fan blade is required to have a fan shroud of 1/16-
inch minimum steel, 360 degrees around the blade. Shroud shall be no more than
one (1) inch from radiator core and one (1) inch past rear blade.
3) All exhausts must discharge vertically or underneath and straight back.
4) Only one (1) automotive type engine per vehicle.