2010 Buick LaCrosse Owner's Manual - Page 278

8-58 Driving and Operating It depends on how the rig is used. For example, speed, altitude, road grades, outside temperature and how much the vehicle is used to pull a trailer are all important. It can depend on any special equipment on the vehicle, and the amount of tongue weight the vehicle can carry. See "Weight of the Trailer Tongue" later in this section for more information. Maximum trailer weight is calculated assuming only the driver is in the tow vehicle and it has all the required trailering equipment. The weight of additional optional equipment, passengers and cargo in the tow vehicle must be subtracted from the maximum trailer weight. Ask your dealer/retailer for trailering information or advice, or write us at our Customer Assistance Offices. See Customer Assistance Offices (US, Can) on page 12‑3 for more information. Trailer Towing (2.4L L4 Engine) Vehicles with a four cylinder engine are neither designed nor intended to tow a trailer. Weight of the Trailer Tongue The tongue load (A) of any trailer is an important weight to measure because it affects the total gross weight of the vehicle. The Gross Vehicle Weight (GVW) includes the curb weight of the vehicle, any cargo carried in it, and the people who will be riding in the vehicle. If there are a lot of options, equipment, passengers or cargo in the vehicle, it will reduce the tongue weight the vehicle can carry, which will also reduce the trailer weight the vehicle can tow. If towing a trailer, the tongue load must be added to the GVW because the vehicle will be carrying that weight, too. See Vehicle Load Limits on page 8‑12 for more information. Trailer Towing (3.0L and 3.6L V6 Engines) Before pulling a trailer, there are three important considerations that have to do with weight: ... The weight of the trailer. The weight of the trailer tongue. The total weight on your vehicle's tires. Weight of the Trailer How heavy can a trailer safely be? For a vehicle with a V6 engine, it should never weigh more than 454 kg (1,000 lbs). But even that can be too heavy.