How To Choose The Correct Electric Winch For A Boat Trailer

Question:

Im confused! I thought the lb rating on winches was to determine appropriate pulling rate. For example, if my pontoon boat not including trailer weighs 2,500 lbs, I should look for an electric winch with at least 3,000 lb line weight. I also read that winches strength is most important for the last 3 ft of boat loading. So, am I overkilling with with a 4,500 lb rated electric winch?

asked by: Nicki K

Helpful Expert Reply:

You are correct in that an electric winch listed weight capacity refers to it's line pull strength. A common ratio for determining your winch load capacity is 2:1. For example, a 2,000-lb boat would require a 1,100-lb winch. There are extenuating factors, however, that will determine the appropriate winch size for your purposes.
The ratio can be stretched to 3:1 in instances when the trailer in use has high-quality rollers and is most commonly used on ramps where boats float most of the way onto the trailer.

In contrast, using a boat trailer that has wooden bunks, lacks self-alignment capabilities, and is most commonly used on ramps where the boat must be winched most of the way onto the trailer reduces the ratio to 1:1.

To calculate your winch's rolling load capacity - the amount of weight it can pull up an incline - you must multiply the winch capacity by a factor determined by the degree of the incline.

The multiplication factor shown includes a 10 percent rolling friction factor. Note: A 5 percent - or 3 degree - incline is a 1/2' rise in 10'. Follow the chart to determine your winch's rolling load capacity which I have attached for you.

Overkill in regards to winches is somewhat of a moot point. Choosing a weight capacity beyond your needs will cause far less stress to be placed on the winch which will in turn improve wear life and longevity.

For a electric winch capable of pulling a 2,500 boat, I recommend using the Dutton-Lainson StrongArm Electric Winch part # DL24870 for a 1:1 ratio and part # DL25532 for both a 2:1 and 3:1 ratio.