2023 - 2025 NPJ Pro Stock GAS 4 X 4 Trucks

(see also GENERAL RULES, which apply for all classes and competitors)

P1.  Weight Class 6300 lbs.
P2.  Truck body must be complete with hood, doors, and bed.  
     The bed must have the floor in place or a top cover in place.  
     No fiberglass bodies allowed. 
     All DOT window glass must be in place.
P3.  Weights cannot be more than 60" from the center of the front axle.  
     Weights in the bed must be secured.  
     No weights are allowed in the cab.
P4.  Any DOT approved tire allowed.  
     Maximum Tire Size 36" diameter X 16" wide.
     Wheels may not be wider than tire width. Example: 14" wide tire on a 14" wide wheel.  
     Tire sharpening allowed, no more than 3/32" (0.093) clearance in backside of tread. 
     No cut, grooved bar tread, or tractor type tires allowed.
P5.  Pump gas, racing fuel, or alcohol allowed.  No Nitromethane or Nitrous allowed.  
     If a truck is equipped with a Nitrous system, the NOS Bottle must be removed in order to compete.
P6.  Open headers allowed.  
     Upright headers allowed. Vertically discharging must be within 10 degrees of plumb.
     Downward header exhausts must discharge under the truck to the rear.  
     No side or down discharge of exhaust toward the ground allowed.
P7. Engine must be naturally aspirated, No supercharger or turbocharger allowed.

      Must be factory bore spacing. Maximum bore spacing allowed 4.900" 

      Single carburetor may be any size. 
      Limited to single plane intake, no tunnel ram, no sheet metal intakes.

      Max intake flow of 525cfm based off the Brodix SR20 BBC head.

      Any advertised head that exceeds this flow number will not be permitted.

P8.  Kill switch or breakaway switch required within 24” of hitch point.  
     All kill switches will be tested at the scale for proper operation.  
     Kill switch must kill the engine and any electric fuel pumps.
     A tie strap will be used to during tech inspection to show vehicle kill switch has been inspected.
     A 1/4" diameter hole will be used to securely hold the tie strap just above the kill switch.
     Only if tie strap is broken, decided by head track official, will competitor be given another attempt.  
P9.  Standard transmissions must have a steel flywheel and a blow-proof bell housing or S.F.I. blanket.  
     Automatic transmissions must have an S.F.I. blanket.
P10.  Drive Shaft loops for the front and rear drive shafts and U-joint shields are required.  
       All U-joints must be shielded 360 degrees with 3/8 aluminum or 5/16 steel.  
       All shields must be 6” long minimum and must be centered over the U-joints.  
       The inside of the shield must not be more than 2” larger than the U-joint.  
       Each truck must have 1 loop for the front drive shaft and 3 loops for the rear drive shaft.
P11.  All drive line components must be for 4X4 vehicles, 1 ton and under weight rating.  
       No drop boxes or reversers.
P12.  Maximum hitch height allowed is 26” from the top of the hitch to level ground. (Hitch can be lower).
       Hitch must be a receiver type-towing hitch or a special constructed pulling hitch.  
       No bumper hitches.  
       Hitch must be rigid in all directions with a minimum of 3 inches wide by 3-3/4 long inside opening.
       No vertical hitch or openings. 
       From point of hook to centerline of rear axle shall be no less than 30% of truck wheelbase and shall 
           not slope any greater than 33 degrees to hitch point. 
       Pivot pin of drawbar can be no farther forward than the center line of the rear axle.
P13.  Suspension modifications are allowed.
       Any blocked or solid suspension must be safely fabricated and securely fastened to the frame as 
              determined by the tech inspector. 
       No Springs required.
P14.  Each truck is required to have an ABC fire extinguisher in the cab and within reach of the driver.
       Extinguisher must be a minimum of 2 ½ lbs.
P15.  Driver must wear a seat belt, fire suit (jacket & pants) and helmet. Helmet must be strapped.
       Driver must wear leather boots or SFI type fire-proof shoes while pulling.
P16.  Truck must have operating front brakes.
P17.  Truck must have rear bumpers at least 8” vertical in height and with a maximum height of 24” off the ground.
P18.  Truck must have a fan shroud.
       Radiator must be ahead of the motor between the grill and the engine.
P19.  No gas tanks, fuel lines or batteries allowed in the truck cab unless factory installed.
       A fuel cell may be used the replace the original tank but must be securely mounted in the bed of 
                                    the truck and shielded entirely by .060" steel or aluminum.
       A fuel tank may be mounted in front of the truck between the weight box and grille of the truck. 
P20.  Axle shields are required.  
       Shield to be .060" thickness steel or aluminum.  
       Shield not to be mounted to axle ends or hub bolts.  
       A single hole may be cut in one to allow locking of hubs.

P21. See Diagram: Frames must be OEM from 8" behind center of front axle to center of rear axle.

      OEM Wheelbase must be retained.

      All frame alterations are subject to Tech Committee approval for safety factors.

P22. For purposes of measuring hitch and weight box distances: 
      a 1" x 1" x 1/4" thick tab is to be welded on top centerline of front and rear axles.

P23. The maximum width of truck may not exceed 102"  (END)


NPJ Modified GAS 4 X 4 Trucks 

(see also GENERAL RULES, which apply for all classes and competitors)
M1. Maximum weight of pulling vehicle is 6,200lbs.

M2. Maximum cubic inch limit is 650. 

M3. Any automotive type engine must be naturally aspirated, with only two valves per cylinder.

M4. Maximum bore spacing allowed is 5.00"

M5. The use of airbags, air shocks, hydraulic cylinders or electric controls as components of a chassis's suspension system is not allowed. This shall not prohibit the of use conventional sealed circuit shock absorbers that have no external plumbing lines or external reservoirs. 

M6. Hitch height maximum is to be 26" at point of hook before, during, & after pull.
    Hitch must be rigid in all directions & mounted solid. 
    Minimum hitch opening to be 3 inches wide by 3-3/4 inches long inside opening.
    Pulling point can be no more than 1.5" from back edge of drawbar.
    No clevis, chains, or cables permitted in hitching device. 
    From point of hook to centerline of rear axle shall be no less than 30% of truck wheelbase & shall not slope any greater than 25 degrees to hitch point.

M7. The use of hydraulic cylinders to retract or extend the position of a weight box is permitted IF:
    A. The cylinders themselves internally limit the travel within the allowable 60". 

    B. During tech it will be pinned at exact position, & must stay in that position during weigh-in, hitch pad adjustment, & competition.

M8. All other rules will follow the P.P.L. Modified 4x4 truck rules. (END)

2024 Daily Driver GAS 

Two wheel drive and Four wheel drive – NO DIESEL
7500 lbs. weight is with driver


See also General Rules, which apply for this and all classes.

B1. Ballast – No hanging front weights.  No hidden weight. No weight in cab.      Any and all ballast must be in the bed of the truck only, and securely fastened.

B2. Batteries in factory location only, securely fastened.

B3. Body  – Tailgate not required. The body must be the OEM truck body. The body must retain full sheet metal. Metal aftermarket hoods are permitted. Fiberglass hoods are permitted with a sheet metal or aluminum skin shield underneath of at least .060” thick. The hood must be closed and securely latched while vehicle is hooked to sled. The complete OEM firewall and OEM floor pan is mandatory. A factory installed pickup bed or commercial style aftermarket bed must be installed.

B4. Brakes – Four wheel hydraulic functional brakes are mandatory.

B5. Chassis – Limited to OEM - “ONE TON” rating maximum.

B6. Cooling- The radiator must be in the stock location and of at least stock size.

B7. Credentials – Valid Inspection, Owners Card, Insurance Card, & Driver’s License. 

B8. Driver Restraint – The OEM restraint system is mandatory and must be worn.

B9. ENGINE, DRIVETRAIN, and SUSPENSION must be same size as mass produced by factory and intended by original manufacturer. Fuel injection will be allowed if factory for that year and make truck. NO suspension modifications. NO cylinder head modifications. NO camshaft modifications. NO intake manifold modifications. NO Superchargers. 

B10. Exhaust to be street legal. Headers allowed but must be street legal. Dual exhaust permitted.

B11. Fire Extinguisher – Recommended.                          

B12. Fuel – Pump Gas Only.                            

B13. Hitch – Must be a receiver-style OEM factory designed towing hitch or standard factory bumper hitch. No special pulling hitches or modified receivers – no bracing. Hooking point must be the rear-most of the vehicle and must be rearward of stock tailgate location. Hitch must be horizontal to the ground and stationary in all directions. Hitch Height from ground may not exceed 26 inches. Hooking point must have a minimum 3 inch wide by 3-3/4 long inside opening for the led to hook. NO CLEVISES. No vertical hitches. Hitch/ Hook point must be in place at scale weigh-in.                                                  

B14. Intercoolers – Factory style or aftermarket intercoolers are permitted. Water-to-air coolers are prohibited. Any means of cooling the air before the engine, except the air-to-air cooler is prohibited.

B15. Interior – A complete interior, including dashboard, door panels, headliner, etc. is mandatory. Two matching seats are mandatory. Aftermarket seats are permitted; they must be fully upholstered. All factory controls (lights, signals, horn, wipers, etc.) must be retained and operative.

B16. Street Equipment – Complete headlight and taillight assemblies (all) are mandatory and must be operative. Complete OEM windshield and windows are mandatory. Windows must be operative per factory specifications; that is, they must open and close via OEM electrical or mechanical means.

B17. Tires – Must be DOT street tires. No cut tires. No loaded tires.

          Maximum 35” OD actual measurement

          Maximum 12” Width actual measurement

            (Trucks utilizing dual rear wheels will be limited to a tire with maximum width of 8” per tire.)

          Maximum 22” Rims

B18. Tow vehicles are prohibited. (END)

New Penn Jersey Tractor Pullers Association Inc.

SINCE 1978


2024 NPJ 6500 lb Enhanced Street GAS Trucks

(see also GENERAL RULES, which apply for all classes and competitors)
G1. Weight Class 6500lbs trucks - KILL SWITCHES REQUIRED - see Pro Stock trucks for specs.
G2. D.O.T. stamped approved street tires only.  
       No cuts, grooved, bar, or tractor type tread.
G3.  The body must be an OEM truck body, including full bed floor. 
       The body must retain all original sheet metal. Tailgate optional.
       Flat bed or homemade bed allowed, but must cover tires and be stock length.
       Metal after-market hoods are permitted.
       Fiberglass hoods are prohibited.
       The hood must be closed and securely latched while vehicle is hooked to sled.
       The complete OEM firewall and OEM floor pan is mandatory.
G4.  Pump gas or race fuel ONLY.  
       No alcohol, nitro or nitrous.  
       If nitrous equipped, bottle must be removed.
G5.  Any type intake manifold and one single four barrel carburetor (or smaller).  
       Air cleaner is required.  
       Factory fuel injection or throttle body system allowed.
G6.  Current DOT or DMV registration, inspection, and insurance card required.  
       Truck must be street legal. NO DEALER TAGS.
       Vehicle must be in same physical condition as at the time inspected for highway use.
       All info will be required at event registration & will be checked.
G7.  Added weight must be secured within the body of the truck.

        No weights allowed in the cab.

        No visible weights except in bed.  
        No front weights or weight boxes allowed. 
        Competitor must be ready and able to show any added weight as being secure  to tech officials.  
        Refusal or omission to show added weight will result in disqualification or ineligibility for competition.
G8.  Hitch must be a receiver-style OEM factory designed towing hitch or standard factory bumper hitch. 
        No special pulling hitches or modified receivers - no bracing.
        Hooking point must the rear-most of the vehicle and

                                 must be rearward of the stock location of tailgate.
        Hitch must be horizontal to the ground and stationary in all directions.
        Hitch Height from ground may not exceed 26 inches.
        Hooking point must have minimum 3 inch wide by 3-3/4 inch long inside opening for the sled to hook.
        NO CLEVISES. 
        No Vertical Hitches.
        The hitch / hook point must be in place at scale weigh-in. 

G9.  All driveline components must be for 4x4 vehicles - "ONE TON" rating maximum.

        Driveshaft loops/ U-joint shielding required (see Pro Stock trucks for specs)   
G10.  Snowplow frames and brush guards are allowed.  
        No homemade bumpers, brackets or weights boxes allowed in this class.  
        Must have stock appearing front bumper.
G11.  No open exhaust permitted.  
        Cat-back aftermarket exhaust systems are permitted.  
        Mufflers are required and headers are allowed.
G12.  Drive shaft loops are highly recommended, but are not mandatory.
          ABC fire extinguisher (minimum 2 1/2 lbs.) must be in cab, within driver's reach.
 G13. Electronics: The use of on-the-fly tuning is prohibited while hooked to the sled.
     No Laptop running on the passenger seat.
     No  adjustments to any onboard computer program while hooked to sled.
G14.  Seat Belt Required.
       Helmet Required.
       Helmet must be strapped. 
G15. Suspension, Front: The upper mounting point for strut assemblies must be in factory location.
                Adjustable caster / camber pillow ball mounts are permitted.
                The lower control arm may be strengthened as long as

                                factory mounting points to chassis are maintained.
                The lower mounting point for strut assembly may be modified for improved caster or camber.
                Strut tower braces, lower tie bars, sway bars, and limit straps are permitted.
                Traction bars and devices are permitted.

G16. Suspension, Rear: An OEM-Style suspension is mandatory.
 Lowering or raising the vehicle height with suspension modifications is permitted.
  Traction bars and devices are permitted.
  They must be bolt-on only; welds are permitted for attachment to frame or axle housing.
 All OEM suspension mounting points must be retained and used.
 Sway bars, limit straps, and camber kits are permitted.
The rear suspension must maintain a MINIMUM compression shock TRAVEL of ONE INCH compression.
 Stops may be adjustable.
All rear suspensions must use at least one working shock absorber per wheel.
Air bag spring assistance is permitted; airbag compressors must be disconnected, no in-cab controls. (END)