N.Y. Comp. Codes R. & Regs. tit. 15 § 57.5
TABLE 1-LIGHT SERVICE DEVICES BREAKING STRENGTH FOR COUPLINGS AND BALLS
Trailer Classification | Trailer Coupling Designation | Minimum Ball Diameter-Inches (where ball-type hitch is used) | Minimum Breaking Point Requirements | Pounds |
| Class 1 (2,000 lbs. Maximum GTW) | No. 1 | 1*7/8 | Longitudinal tension: | 6,000 |
| Longitudinal compression: | 6,000 | |||
| Transverse thrust: | 2,000 | |||
| Vertical tension: | 2,500 | |||
| Vertical compression: | 2,500 | |||
| Class 2 (3,500 lbs. Maximum GTW) | No. 2 | 2 | Longitudinal tension: | 10,500 |
| Longitudinal compression: | 10,500 | |||
| Transverse thrust: | 3,000 | |||
| Vertical tension: | 3,900 | |||
| Vertical compression: | 4,500 | |||
| Class 3 (5,000 lbs. Maximum GTW) | No. 3 | 2 | Longitudinal tension: | 15,000 |
| Longitudinal compression: | 15,000 | |||
| Transverse thrust: | 4,000 | |||
| Vertical tension: | 3,900 | |||
| Vertical compression: | 7,000 | |||
| Class 4 (5,000 +thru 10,000 lbs. Maximum GTW) | No. 4 | Ball and bolt shall be of such size and strength as to conform to the minimum breaking strength requirements of the mating coupling required for the specific load of Class 4 Trailer. | Longitudinal tension: Max. GTW x 3 | |
| Longitudinal compression: Max. GTW * 3 | ||||
| Transverse thrust: Max. GTW * 1 | ||||
| Vertical tension: 3,800 +Max GTW ÷ 50 | ||||
| Vertical compression: Max. GTW * 1.4 |
TABLE 2-HITCH TEST FORCES
| STEP | WEIGHT CARRYING HITCH | WEIGHT DISTRIBUTING HITCH | ||
Force | Direction | Force | Direction | |
| a | V = .47R + 480 | Downward | V = .045R + 1650 | Downward |
| L = .47R + 480 | Compressive | M = 51,000 | See Figure 1 | |
| b | L = .23R + 1530 | Tensile | L = .067R + 2070 | Tensile |
| V = .15R | Downward | V = .15R | Downward | |
| c | Compressive | L = .067R + 2070 | Compressive | |
| Downward | V = .15R | Downward | ||
| d | T = .20R + 500 | Leftward | T = .20R + 500 | Leftward |
| e | T = .20R + 500 | Rightward | T = .20R + 500 | Rightward |
| f | Not Applicable | Not Applicable | M = 112,000 | See Figure 1 |
| V = .15R | Downward | |||
_____________________________________________________
V = Vertical Force (lbs.)
L = Longitudinal Force (lbs.)
T = Transverse Force (lbs.)
M = Spring Bar Moment (inch-lbs.)
R = Hitch Rating in Terms of GVWR (lbs.)
_____________________________________________________
All forces in steps (a) through (e) are to be applied along an axis which intersects the center of the ball. All forces are to be applied with an onset rate of not more than 150 pounds per second, and maintained at the maximum specified force level for at least five seconds.
TABLE 3-MAXIMUM RECOMMENDED TONGUE WEIGHTS BY TRAILER CLASSIFICATION FOR TRAILER DESIGN
Class Trailer | Maximum Gross Trailer Weight, lb | Maximum Static Tongue Loads, lb | Recommended Type of Hitch |
| 1 | Up to 2000 | 200 | Weight carrying hitch |
| 300 | Weight distributing hitch | ||
| 2 | 2000 to 3500 | 300 | Weight carrying hitch |
| 500 | Weight distributing hitch | ||
| 3 | 3500 to 5000 | 15% gtw* | Weight distributing hitch |
| 4 | 5000 to 10,000 | 15% max gtw* | Weight distributing hitch |
* Gross trailer weight.
TABLE 4--LIGHT SERVICE DEVICES--MINIMUM STRENGTHS OF SAFETY CHAINS AND ATTACHING MEANS*
| Minimum Longitudinal Load, Tension, Pounds (See Figures 2 and 3) | ||
| Trailer Classification | Each Safety Chain | Each of Two Chain Attaching Means |
| Class 1 | 2,000 | 2,000 |
| Class 2 | 3,500 | 3,500 |
| Class 3 | 5,000 | 5,000 |
| Class 4** | Maximum GTW | Maximum GTW |
* Load shown shall be applied in the same manner as would prevail if the trailer were being towed by the safety chain in a straight ahead direction. Safety chain, when formed, fastened or rigged as on the vehicles, shall withstand load shown without breaking. Local marking, denting or gouging of the chain attaching means at the points of safety chain contact shall not be considered excessive distortion. The intent is that the chain attaching means shall have sufficient strength to break the safety chain consistently.
** "Maximum GTW" means the maximum gross trailer weight, pounds, which is to be towed.
Footnotes
* Gross trailer weight.
** "Maximum GTW" means the maximum gross trailer weight, pounds, which is to be towed.
N.Y. Comp. Codes R. & Regs. Tit. 15 § 57.5