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To connect our truck to our trailer, we back our truck

up to our trailer, run the trailers jack down so thatthe trailers coupler drops over the ball on the truck,

snap the coupler closed, attach the trailers safetychains and break away system cable to the truck, and

connect the trailers electrical systems to the truck by

inserting the trailers electrical plug into the truckselectrical receptacle. And to disconnect our truck

from our trailer, we mindlessly do the same steps, but

in reverse.

Normally, we do not think much about thecomponents of the truck and trailer that connect

together. However, we should pay much moreattention to the connection of our truck and trailerbecause our safety and the safety of our horses

depend upon the connection.

The first thing to do before connecting your trailer to

your truck is to perform a visual inspection of allcomponents that connect your truck to your trailer. If

you use your trailer infrequently, you should

establish a regular periodic inspection schedule and

adhere to it.

Bumper Pull Hitch A bumper pull hitch ismounted to the rear end of the frame of your

tow vehicle. The hitch exits the rear of your

tow vehicle below the bumper. The hitch hasa hollow square tube into which is inserted a

draw bar. There is a hole through the hollow

square tube for inserting a draw bar pin.Inspect the tightness of the bolts that attach

the hitch to the frame of your tow vehicle.

Inspect the hitch for cracks and the conditionof the welds holding the pieces of the hitch

together. Inspect the hollow square tube for

cracks and the hole for the draw bar pin for

wear.

Bumper Pull Draw Bar There are twotypes of draw bars: 1) dead weight; and 2)weight distributing.

A dead weight draw bar is a square hollowsteel tube or solid steel bar with a flat steel

plate welded to it. The hitch ball is attached

to the draw bar through a hole in the flat steel

plate. The draw bar pin goes through a holein the square part of the draw bar to hold the

draw bar in the hitch. Inspect the square

steel and flat steel parts of the draw bar forcracks or brakes and check the condition of

the weld between them.

A weight distributing draw bar is a solid, l-shaped, square steel bar with a spring barassembly and ball mount attached to one end

of it. The other end is inserted into the

square tube of the bumper pull hitch. Thedraw bar pin goes through a hole in the end

without the spring bar assembly to hold the

weight distributing draw bar in the hitch.

Inspect the l-shaped square steel bar forcracks or breaks. Inspect the spring bar

assembly and ball mount for cracks, breaks,

loose bolts, and the condition of its welds.

Bumper Pull Draw Bar Pin The draw barpin is a hardened steel pin with a 0.625 inch

diameter. One end is bent or has a loop

welded to it and the other end has a hole orslot in it for attachment of a clip. The bend

or loop and the clip on opposite ends of the

draw bar pin keep it in place once it is

inserted through the square tube of the hitchand draw bar. Inspect the draw bar pin for

wear, cracks, and the hole or slot for wear.

Bumper Pull Hitch Ball A bumper pullhitch ball is the focal point of the connectionbetween your tow vehicle and your bumper

pull trailer. The ball is sized appropriately

for the class of the hitch. A Class I hitchrequires a 1 7/8-inch diameter hitch ball with

a 3/4-inch shank. A Class II hitch requires a

2-inch diameter hitch ball with a 1-inchshank. A Class III hitch requires a 2 5/16-

inch diameter hitch ball with a 1-inch shank.

A Class IV hitch requires a 2 5/16-inchdiameter hitch ball with a 1 1/4-inch shank.Inspect the ball for wear, it should be round

not elliptical, and it should not have any

cracks or breaks. The nut holding the hitchball tight to the draw bar must be tight.

Ideally, it should be tightened with a torque

wrench to at least 120 lb-ft of torque. Also,it is extremely important that the shank of the

hitch ball is the same size as the hole in the

draw bar. If the shank is smaller than theHorseWheels Volume 1 Issue 1 - Page

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hole, no matter how tight you get the hitch

ball, it can move in the hole and create a

dangerous situation.

Gooseneck Hitch A gooseneck hitch ismounted through the bed of your tow vehicle

and attached to its frame by welds, bolts, or

both. A gooseneck hitch has two basic parts:1) a mount for the hitch ball; and 2) base rails

which connect the ball mount to the tow

vehicles frame. Inspect the ball mount and

base rails for cracks or breaks, loose bolts,and the condition of its welds. If the ball

mount moves, has a mechanism to fold the

ball into it, or move the ball under the bed,inspect the mechanism for proper and easy

operation.

Gooseneck Hitch Ball A gooseneck hitchball is the focal point of the connection

between your tow vehicle and yourgooseneck trailer. The ball is 2 5/16-inch in

diameter with at least a 1 1/4-inch shank.

Inspect the ball for wear, it should be roundnot elliptical, and it should not have any

cracks or breaks. If the hitch ball is held to

the ball mount with a nut, the nut must betight. Ideally, it should be tightened with a

torque wrench to at least 120 lb-ft of torque.

If the hitch ball is tightened directly into theball mount, it should be tightened into the

ball mount with a similar amount of torque.

If the ball is held in the ball mount byanother type of mechanism, be sure the

mechanism is functioning properly and

holding the ball firmly.

Electrical Receptacle A receptacle withseven pins that accepts a 7-pin plug from atrailer. The receptacle and plug contain a pin

connection to link the trucks ground with

the trailers ground. The other six pinsconnect six electrical circuits: 1) tail lights;

2) brake lights; 3) left turn signal; 4) rightturn signal; 5) electric brakes; and 6) backuplights. The trucks receptacle is normally

located either next to the rear license plate or

under the rear bumper next to or on the hitch.

Electrical Wiring The trucks electricalwiring for a trailer connection is spliced into

the six circuits mentioned directly above. Ifthe truck has anti-lock brakes, the electric

brake circuit must be integrated with it andwork with it.

Jack Assembly The jack assembly lifts thetrailers coupler off of the ball attached to thetruck. Jacks are either manual or electric.

Both require lubrication to work smoothly,

lightly apply water pump grease or

penetrating oil like WD40 on the part of the

jack that extends and the mechanism thatturns to extend the jack.

Landing Gear There are two types oflanding gear: for a gooseneck trailer and for a

bumper pull trailer.

Gooseneck trailer landing gear looks similarto a large steel foot. Its function is to

provide a solid, flat end for the jack so thatthe jack does not cut into the ground with

detaching the trailer. The landing gear

should be a considerable distance from the

ground when the trailer is in motion so that itwill not come in contract with the ground and

cause serious damage to the trailer.

Bumper pull trailer landing gear is normallya removable wheel that slips onto the end of

the jack when the trailer is being detached

from the truck and is removed from the endof the jack when the trailer is attached to the

truck. The wheel should not be left on the

jack when the trailer is attached to the truckas it may come in contact with the ground

while the trailer is in motion and may causeserious damage to the trailer.

Coupler The coupler is attached to the endof the tongue of a bumper pull trailer and to

the lower end of the gooseneck of a

gooseneck trailer. The coupler closes around

the ball on the truck to lock the trailer to thetruck. The most important thing about a

coupler is that it must be the same size as the

ball that is being mated with it. If the ball issmaller than the coupler, the ball will move

within the coupler and may come out of the

coupler. If the ball is larger than the coupler,the coupler will not close properly around the

ball and may come out of the coupler.

Safety Chains If for some reason a trailerscoupler fails, or the coupler opens and comes

off the ball of the tow vehicle, safety chains

maintain a connection between the trailer andthe tow vehicle. Without safety chains, if a

coupler failure occurred, the trailer would bePage 2 - HorseWheels Volume 1 Issue 1

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loose and be hazardous to other vehicles and

to its contents. Safety chains are normally

welded close to the coupler on the tongue ofa bumper pull trailer or the connecting post

of a gooseneck trailer. Safety chains should

be sufficiently strong to hold the trailer to thetow vehicle. The welds connecting the safety

chains to the trailer should be solid and free

from cracks and rust.

Breakaway Brake System The breakawaysystem is comprised of three elements: 1) theconnection cable; 2) the breakaway switch;

and 3) the breakaway battery. The

connection cable attaches the trailersbreakaway switch to the tow vehicle. The

connection cable usually has a loop on one

end that is placed over the ball on the towvehicle before the trailers coupler is lowered

onto it. The breakaway switch is normally

attached to the tongue of a bumper pulltrailer close to the coupler and on thegooseneck post on a gooseneck trailer. The

breakaway battery is attached to the

breakaway switch and to the trailers brakecircuit.

If the trailer separates from the tow vehicle,

the connection cable will remain attached to

the tow vehicle and will pull a pin out of thebreakaway switch. When the pin is pulled

out of the breakaway switch, a circuit is

completed between the breakaway batteryand the trailers brakes causing the brakes to

be applied and stop the trailer independently

of the tow vehicle.

Electrical Plug The electrical plugconnects all of the trailers electrical circuits

to the appropriate tow vehicles electrical

circuits. The electrical plug has seven pins,one for each of the trailers six circuits and a

ground. Refer above to the trucks Electrical

Receptacle and Electrical Wiring. Electrical Wiring The trailer normally has

six circuits and a ground. Refer above to thetrucks Electrical Receptacle and Electrical

Wiring.

HorseWheels Volume 1 Issue 1 - Page