What Size Winch for Car Trailer? – Complete and Thorough Guide

New to the world of winches? These seemingly simple yet versatile devices are not just hooked cables for pulling and lifting; they encompass much more. Essentially, a winch serves as a hoisting or hauling apparatus, featuring a rope or chain wound around a horizontally rotating drum. Its power source lies in a motor connected to a gearbox, driving a crankshaft linked to the rotating drum.

For those venturing into the realm of car trailer winches, the array of options may be overwhelming. As a crucial gadget to have on hand, selecting the right winch size is pivotal. The challenge arises from the diverse market offerings and the varying weights and sizes of vehicles.

In this exploration, we unravel the mysteries surrounding winch sizes, guiding you towards making an informed decision. Stick around for insights that will steer you in the right direction on your quest for the perfect winch.

Best Car Tailers Winch

Types of winches for Car Trailers

Car trailer winches are mainly categorized in two groups, hydraulic winches and electric winches. Primarily both of the types perform the same function but the mechanism of doing that is different, in terms of their running durations, capacities and also fueling and power supply.

1. Hydraulic Winches

 A hydraulic winch is a manually propelled device which uses a power steering pump to operate. It enables you to pull heavy objects, or more importantly your vehicle against forces of friction and gravity, by multiplying your strength. More importantly, hydraulic winches are equipped with a ratchet that holds the object being pulled at any point on your trailer.

It has the benefit of running for longer periods of time without any signs of heating up. It enables a normal person to carry out heavy duty pulling with simple crank and gear train mechanisms, however it has the disadvantage of being more expensive compared to the electric winches.

2. Electric Winches

Electric winches make use of DC motors powered by the tow car’s battery system, as they don’t have their own power systems. Due to being low priced, electric winches are more common amongst users, but they are not as useful as hydraulic winches when it comes to handling heavy loads. However, some of the models make use of a pulley to increase their pulling power. Operating electric winches for extended periods of time can lead to issues such as overheating, therefore, they are appropriate to be used for medium level loads like pulling cars rather than trucks and SUVs.

The best winch size for a Car Trailer?

The capacity and pulling power of a winch depends a lot upon its size. Larger winches are likely to be more powerful than smaller ones, so they can generate greater amounts of torque to pull heavy vehicles like trucks. However, going for the biggest winches regardless of your trailer size is not a good idea as most of the times trailers do not support winches of all sizes. On the contrary, getting a smaller winch wouldn’t work out either as it would be prone to break and would not be as reliable as you need for emergency situations.

The size of the winch should henceforth be compatible with your vehicle for proper utility. The two main factors you will need to consider in this regard are the gross weight of the car you pull and the rated capacity of the winch. The GVW or the gross vehicle weight takes in account the curb weight of the vehicle as well as the load in the vehicle due to luggage or passengers stuck.

After you determine the gross weight of your vehicle, you calculate the rolling load. It is usually just 25% of the gross weight because when you are pulling on tractors, cars or trucks on to the trailer bed, they have wheels which make the amount of pulling force required less than the weight of vehicle. Therefore, your winch can pull a lot more gross weight than its rated pull line capacity.

The winch rated capacity is the maximum amount of load a winch can haul, depending upon the size of the winch. It should be at least 1.5 times the rolling load or the gross weight (if you are pulling against gravity), for safe use. So for instance you want to pull a car out of a deep ditch on to a trailer bed, which weighs about 5000 lbs, then the pulling capacity of the winch should be minimum 7500 lbs. This will allow the winch to comfortably handle the weight of the car even if it has to endure all of it. It also accounts for any extra load on the car, so you won’t need to worry about unloading the car first.

Other factors to look for in your Winch?

There are some other factors that you should take in consideration for sure before buying a winch for your car trailer. Keep a budget in mind first and look for options within that, but remember if you buy a very cheap one, it will eventually cost you more in the future. Therefore, if you want to buy a reliable one which lasts long, you shouldn’t be worried about spending some extra bucks.

Installation of the winch should be easy, as if you get a complex one, it will get you frustrated and then you’ll have to spend money to hire a professional installer. So look for and buy an easy to install winch, which you can mount and dismount from your trailer at any time.   


Selecting the ideal winch size for your car trailer will surely be a tough decision to make. Therefore, it is necessary to spend enough time to determine the perfect size according to your needs. We hope that this article would have helped you a lot in this regard.

Frequently Asked Questions

  1. How do you calculate winch pulling power?

Operating winches at higher speeds requires greater amount of power. This can be calculated by using the formula Power (kW) = Force (N) x Velocity (m/min)/1020×60.  

  1. How strong is quarter inch winch cable?

A 1/4” winch cable of the WSC 7×19 galvanized type has a rated breaking strength of approximately 7000 lbs.

  1. Can you use a winch on an incline?

Winches can surely be used on inclined surfaces, however as the angle of incline increases, the pull line capacity of the winch reduces as gravity has increased effect at greater incline angles.

Leave a Comment