GLAD HANDS

USA Fleet Supply offers a full line of Glad Hands, Seals, Grips and accessories. Aluminum glad hands, metal glad hand locks, universal glad hands, plastic glad hands, single and double lip glad hand seals, glad hand grips and more.

Glad hands are coupling devices used to connect the service and emergency air lines from the truck or tractor to the trailer. Couplers have a rubber seal that prevents air from escaping. You should clean the couplers and rubber seals before a connection is made. When connecting glad hands, press the two seals together with the couplers at a 90° angle to each other. A turn of the glad hand attached to the hose will join and lock the couplers in place.

It is very important to keep the air supply clean. To keep the air supply clean, some vehicles have dead end or dummy couplers to which the hoses may be attached when they are not in use. This will prevent water and dirt from getting into the coupler and the air lines. Use the dummy couplers if available when the air lines are not connected to a trailer.

To avoid mistakes, metal tags are sometimes attached to the lines with the words "service or emergency" stamped on them. Sometimes colors are used. Blue is used for the service lines and red for the emergency lines.

If you do cross the air lines, supply air will be sent to the service line instead of going to charge the trailer air tanks. Air will not be available to release the trailer spring brakes (parking brakes). If the spring brakes don't release when you push the trailer air supply control, check the air line connections.

View our Glad Hands, Seals and Grips

Older trailers do not have spring brakes. If the air supply in the trailer air tank has leaked away there will be no emergency brakes and the trailer wheels will turn freely. If you crossed the air lines, you could drive away but you would not have trailer brakes. Before driving, always test the trailer brakes with the hand valve or by pulling the air supply control. Pull gently against them in a low gear to make sure the brakes work.

Air brake glad hands are coupling devices used to connect the service lines (blue) and emergency air lines (red) from the truck or tractor to the trailer. 

Browse our Glad Hand catalog now. If you need help finding the right product for you, please do not hesitate to ask a Glad Hand product representative.