GM Service Manual Online
For 1990-2009 cars only

Before installing a snow plow on your vehicle, here are some things you will need to know:

Notice: If your vehicle does not have the snow plow prep package, adding a plow can damage your vehicle, and the repairs would not be covered by warranty. Unless your vehicle was built to carry a snow plow, do not add one to your vehicle. If your vehicle has the snow plow prep package, called RPO VYU, then the payload your vehicle can carry will be reduced when a snow plow is installed. Your vehicle can be damaged if either the front or rear axle ratings or the Gross Vehicle Weight (GVW) are exceeded.

Question:

How do I know if my vehicle can handle a snow plow?

Answer:

Some vehicles are built with a special snow plow prep package, called RPO VYU. If your vehicle has this option, you can add a plow to it, provided certain weights, such as the weights on the vehicle's axles and the Gross Vehicle Weight (GVW), are not exceeded.

Question:

How heavy can a snow plow safely be?

Answer:

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

    • The options your vehicle came with, and the weight of those options.
    • The weight and number of passengers you intend to carry.
    • The weight of items you have added to your vehicle, like a tool box or truck cap.
    • The total weight of any additional cargo you intend to carry.

Say, for example, you have a 700 lb (318 kg) snow plow. The total weight of all occupants and cargo inside the cab should not exceed 300 lb (135 kg). This means that you may only be able to carry one passenger. But, even this may be too much if you have got other equipment already adding to the weight of your vehicle.

Here are some guidelines for safely carrying a snow plow on your vehicle:

    • Make sure the weight on the front and rear axles does not exceed the axle rating for each.
    • For the front axle, if more cargo or passengers must be carried, appropriate counter ballast must be installed rear of the rear axle. Counter ballast must be properly secured so it will not move during driving.
    • Follow the snow plow manufacturer's recommendations regarding rear ballast. 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 axle rating.
    • The snow plow manufacturer or installer can assist you in determining the amount of rear ballast required, to help make sure your snowplow/vehicle combination does not exceed the GVW rating, the front and rear axle ratings, and the front and rear weight distribution ratio.
    • The total vehicle must not exceed the GVW rating.

Question:

What is front axle reserve capacity, and how do I calculate it?

Answer:

Front axle reserve capacity is the difference between your front Gross Axle Weight Rating (GAWR) and the front axle weight of your vehicle with full fuel and passengers. Basically, it is the amount of weight you can add to your front axle before reaching your front GAWR.

The front axle reserve capacity for your vehicle can be found in the lower right corner of the Certification/Tire label, as shown.

United States


Object Number: 808973  Size: A2

Canada


Object Number: 809062  Size: A2

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


Object Number: 808971  Size: B3

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

Where:

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

(W x (A + W.B.))/W.B. = (700 x (4 + 10))/10 = 980 lbs (445 kg)

So, if your truck's front axle reserve capacity is more than 980 lbs (445 kg), you could add the snow plow without exceeding the front GAWR.

Question:

What if I want to add heavier equipment to my vehicle?

Answer:

You can add heavier equipment on the front of the vehicle if you compensate for it by carrying fewer passengers, less cargo, or by positioning cargo towards the rear. This has the effect of reducing the load on the front. However, the front GAWR, rear GAWR, and the Gross Vehicle Weight Rating (GVWR) must never be exceeded.

Caution: On some vehicles that have certain front mounted equipment, such as a snow plow, it may be possible to load the front axle to the front gross axle weight rating (GAWR) but not have enough weight on the rear axle to have proper braking performance. If your brakes can not work properly, you could have a crash. To help your brakes work properly when a snow plow is installed, always follow the snow plow manufacturer or installer's recommendation for rear ballast to ensure a proper front and rear weight distribution ratio, even though the actual front weight may be less than the front GAWR, and the total vehicle weight is less than the gross vehicle weight rating (GVWR). Maintaining a proper front and rear weight distribution ratio is necessary to provide proper braking performance.

Question:

What is total vehicle reserve capacity?

Answer:

This is the difference between your GVWR and the weight of your truck with full fuel and passengers. It is the amount of weight you can add to your vehicle before reaching your GVWR. Keep in mind that reserve capacity numbers are intended as a guide when selecting the amount of equipment or cargo your truck can carry. If you are unsure of your vehicle's front, rear, or total weight, go to a weigh station and weigh your vehicle. Your dealer can also help you with this.

The total vehicle reserve capacity for your vehicle can be found in the lower right corner of the Certification/Tire label as shown previously.

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

Emergency Roof Lamp Provisions

Vehicles with the RPO VYU snow plow prep package also have an emergency roof lamp provision package, RPO TRW. Wiring for the emergency roof lamp is provided in the B-pillar as shown. See Auxiliary Roof Mounted Lamp for switch location.


Object Number: 1552322  Size: B4
  1. Body Side Inner Panel

  2. Emergency Roof Lamp Harness