What’s the Right Wire for the Job?

By: Leigh M

Gauge, material, application and run length. All important factors to consider when replacing the wiring on your truck. The simplest way to ensure you’re using the correct wire is to put in exactly what you’ve taken out, but that’s not always the possible. When this happens, you need to know what to consider when choosing the replacement wire. Make sure you take your time to choose the right one, under sizing a wire can be dangerous to driver and truck while a wire that is too big will cause components to work incorrectly, or not at all


First consideration is the wire material. You should never be using a solid core wire; they are less flexible and more prone to breaking due to vibrations coming from the truck. Next is the wire type, Copper is always the best option but there are a few other types, mainly OFC (Oxygen Free Copper) and CCA (Copper Clad Aluminum). Using aluminum as a wire is fine, but you must keep in mind its drawbacks; it’s less efficient than copper by about 40%. What’s the practical application of that? It heats up more and you need a thicker gauge. Aluminum is also prone to corrosion which can reduce the efficiency of the wire.

Wire Gauge

Next is your wire gauge, or the thickness of your wire. This determines how much current the wire can handle. Are you wiring a light? A sensor? Power windows? They all need a different gauge because they all use different amperages.

Something else to keep in mind is the length of the wire run. The run to your front signal light and your trailer taillights are very different and thus need a different wire as a result. This is due to voltage drop, wires aren’t perfect conductors and some of the energy is naturally lost as it travels down the line in the form of heat. Most applications assume a 3% power loss, but 10% power loss should be used if it is a system critical component. There are several charts available online displaying the gauge vs. amperage vs. distance relationship, so

Choosing the right wire is important as it has safety implications if done incorrectly. Always be sure you know what you are doing before working on a trucks electrical system. If you find you need a hand, call one of our branches, our parts department will be able to advise you on best practices and products for your job. Or, let us take care of the whole job by bringing your truck to one of our service centres, we’ll have a technician take a look at the problem and make any necessary repairs along the way. To find a Parts for Trucks near you, click here