2021 GMC Sierra 1500 Owners Manual - Conversions and Add-Ons

Conversions and Add-Ons

Add-on equipment can drain the vehicle's 12-volt battery, even if the vehicle is not operating.

The vehicle has an airbag system. Before attempting to add anything electrical to the vehicle, see Servicing the Airbag-Equipped Vehicle 0 69 and

Adding Equipment to the Airbag-Equipped Vehicle 0 69.

For information on wiring auxiliary switches, see www.gmupfitter.com or contact your dealer.

Before installing a snow plow on the vehicle, follow these guidelines:

The plow the vehicle can carry depends on many things, such as:

The options the vehicle came with, and the weight of those options.

The weight and number of passengers to be carried.

The weight of items added to the vehicle, like a tool box or truck cap.

The total weight of any additional cargo to be carried.

To safely carry a snow plow on the vehicle:

With a snow plow attached, the engine coolant temperature gauge may show a higher temperature than while driving without one. The snow plow could block the airflow to the radiator. This could be more noticeable as vehicle speed increases. At speeds above 72 km/h (45 mph), this may cause the engine coolant to overheat. Move or angle the snow plow blade to allow increased airflow to the radiator.

To increase the airflow, move the snow plow blade position.

If driving more than 24 km/h (15 mi), angle the plow blade position.

Make sure the weight on the front and rear axles does not exceed the axle rating for each.

Follow the snowplow manufacturer’s recommendations for any rear ballast that may be required. Rear ballast may be

required to ensure a proper front and rear weight distribution ratio even though the actual weight at the front axle may be less than the front axel rating.

The snowplow manufacturer or installer can assist in determining the amount of rear ballast required to ensure that the

vehicle with the attached snowplow does not exceed the GVW rating, the front and rear axle ratings, or the front and rear weight distribution ratio.

Front axle reserve capacity is the difference between the Front Gross Axle Weight Rating (GAWR) and the front axle weight of the vehicle with full fuel, passengers, and any other cargo. This is the amount of weight that can be added to the front axle before reaching the Front GAWR.

To calculate the amount of weight any front accessory, such as a snow plow, is adding to the front axle, use this formula:

(W x (A + W.B.)) /W.B.= Weight the accessory is adding to the front axle.

Where:

W = Weight of added accessory

A = Distance that the accessory is in front of the front axle

W.B. = Vehicle Wheelbase

For example, adding a 318 kg (700 lb) snow plow actually adds more than 318 kg (700 lb) to the front axle. Using the formula, if the snow plow is 122 cm (4 ft) in front of the front axle and the wheelbase is 305 cm (10 ft), then:

W = 318 kg (700 lb)

A = 122 cm (4 ft)

W.B. = 305 cm (10 ft) (W x (A + W.B.)/W.B. = (318 x (122 + 305))/305

= 445 kg (980 lb)

This means if the front axle reserve capacity is more than 445 kg (980 lb), the snow plow could be added without exceeding the

front GAWR.

Heavier equipment can be added on the front of the vehicle if less cargo or fewer passengers are carried, or by positioning cargo toward the rear. This reduces the load

on the front. However, the front GAWR, rear GAWR, and Gross Vehicle Weight Rating (GVWR) must never be exceeded.

We are aware that some vehicle owners might consider having the pickup box removed and a commercial or recreational body installed. Owners should be aware that, as manufactured, there are differences between a chassis cab and a pickup with the box removed which could affect vehicle safety. The components necessary to adapt a pickup to permit its safe use with a specialized body should be installed by the body builder.

See your dealer for additional advice and information about using a snow plow on the vehicle. Also, see Vehicle Load Limits 0 221.