tow bar INFINITI Q70 HYBRID 2018 Towing Guide
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 2018 INFINITI Towing Guide   
 
5
 
BALL MOUNT  
A ball mount (also known as a drawbar) is a bar that holds a hitch ball and is inserted into a 
receiver-type hitch. Ball mounts come in a number of weight capacities (3,500 lbs., 5,000 lbs., etc.) 
and sizes (1 1/4”, 2”, etc.), and can be weight-distributing or non-weight-distributing.  Choose a 
proper class ball mount based on the trailer weight. 
 
HITCH BALL 
A hitch ball is bolted through a ball mount or a hitch hole 
in the tow vehicle’s rear bumper. The coupler on the 
trailer tongue attaches over the hitch ball. 
Like ball mounts, hitch balls are available in a number of 
weight capacities and sizes. Always make sure the hitch 
ball selected has the proper shank diameter and weight 
rating for the ball mount as well as the coupler on your 
trailer. Using a 1 7/8” hitch ball in a 2” coupler, for 
example, could result in the trailer separating from the tow vehicle.  The required hitch ball size is 
stamped on most trailer couplers.  
The diameter of the hitch ball shank must be matched to the ball mount hole diameter. The shank 
should be no more than 1/16” smaller than the hole in the ball mount.  To keep the hitch ball in top 
condition, a simple maintenance routine is recommended.  Coating it with light grease will 
minimize wear of both the coupler and hitch ball. Also, by removing the hitch ball when not towing, 
or by protecting it with a special cover, you will help prevent rust from forming on it. 
Hitch
Mount BallBall 
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 2018 INFINITI Towing Guide   
 
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TOWING GLOSSARY  
   
 
 
  
  BALL MOUNT A bar that holds the hitch ball and is inserted into the hitch receiver. Also 
commonly called a drawbar. 
  BREAKAWAY SWITCH A safety device using a trailer battery that automatically applies the trailer’s 
brakes if it should accidentally become separated from the tow vehicle. A 
breakaway switch may be used with both electric or surge trailer brake systems. 
  BUMPER HITCH A reinforced bumper designed to accommodate a hitch ball. 
  ELECTRIC TRAILER  BRAKES When the brakes on a tow vehicle are applied, an electric current is sent to an 
actuator which applies the trailer’s brakes. 
  ELECTRIC TRAILER  BRAKE CONTROLLER A device that controls the electric trailer brakes. 
  GROSS AXLE  WEIGHT RATING (GAWR) The maximum amount of weight each vehicle axle (front and rear) is designed to 
safely carry.     
   GROSS COMBINED  WEIGHT RATING (GCWR) The maximum allowable combined weight of the vehicle and trailer, including 
passengers and all cargo. 
   GROSS VEHICLE 
WEIGHT RATING (GVWR) The maximum allowable weight of the vehicle, including passengers, cargo, fuel, 
hitch, trailer tongue load, and any optional equipment. 
   HITCH BALL 
 A ball that connects the trailer to the tow vehicle hitch that provides the means 
by which the trailer pivots during cornering.  Available in a number of sizes and 
weight capacities, it must correspond to the trailer coupler size, and have a 
sufficient capacity rating for the trailer being pulled.
    RECEIVER HITCH A frame- or structure-mounted hitch with a receiver that allows removal of the ball 
mount.
    SAFETY CHAINS/CABLES Provides an emergency connection between the tow vehicle and the trailer, 
should the trailer become disengaged for any reason.
    SURGE BRAKES 
 Hydraulic-type braking system activated by inertia. As the tow vehicle begins to 
brake, the trailer pushes against the hitch ball, consequently activating the trailer 
brakes.  
    TRAILER TONGUE/COUPLER The part of the trailer that extends forward to meet the tow vehicle, and carries 
the coupler assembly.
    TRAILER TONGUE 
LOAD The amount of trailer weight pressing down on the hitch. 
   WEIGHT-DISTRIBUTING 
HITCH SYSTEM Type of hitch system that helps shift the trailer tongue weight to all trailer tires 
and the tow vehicle front tires. Strongly recommended when towing trailers with a 
Maximum Trailer Weight greater than 5,000 lbs.   
   WIRING HARNESS 
 Provides an electrical connection linking the tow vehicle’s electrical system to the 
trailer’s system.