How To Choose Winch Size For Car Trailer: A Simple Guide

It's hard to imagine a more powerful and versatile device than a car trailer winch. It can manage a lot of different difficult tasks that might seem daunting or even impossible without it. Whether you want to rescue a heavy vehicle from the clutches of thick mud or navigate through rugged terrains without fear, you should definitely have a trusty winch by your side. 

Key Takeaways:

  • Choosing the right size for a car trailer winch, defined primarily by its load capacity, is essential for safety, operational efficiency, and the device's longevity. 
  • With a car trailer winch, the term "size" predominantly denotes its load capacity or pulling strength. 
  • An excessively large winch can introduce additional weight, consume more power, and dent your pocket. 
  • A winch that's too small poses risks as it may not meet task demands, potentially leading to accidents or equipment damage.

Don't let its simplicity fool you, though. If you think that the bigger the winch, the better, it's not always true. Choosing the correct size of a car trailer winch strongly depends on what weight you're going to pull with that winch.

It really matters because, with a well-suited winch, you can successfully tow or pull almost anything you want and even lift heavy loads onto the trailer. This potential makes it an essential tool for both occasional outdoor activities and for professional work as well.

The possibilities are nearly endless. Once you realize that you need a winch in your vehicle and install one, you will find more and more different things you can do with it. It's a useful tool that can be a good solution to many problems, even the least expected ones.

What Is A Car Trailer Winch?


In its essence, a car trailer winch is a simple mechanical device that consists of a cable wrapped around a drum. The cable itself is equipped with a hook at the end to make it easier to secure whatever it needs to be. Both the drum and the cable are powered by a small motor that works efficiently and steadily while you pull or lift things onto the trailer.

The winch is typically mounted either on the bumper of the vehicle or directly onto the ramp of a trailer. In the case of a trailer winch, it's obviously secured on the ramp. This positioning is ideal for tasks like rescue, recovery, loading, and unloading.

The main reason trailer winches exist is to make these tasks as simple and manageable as possible. They also allow for improved safety while loading and unloading cargo on and off the trailer.

What Does Winch Size Mean?


Car trailer winches are usually divided into categories based on their load capacity and power ratio. Usually, when talking about sizes, we expect to see physical dimensions like length, width, and height. But car winches are different in this respect, and their size usually refers to how powerful they are.

When you're being asked what size winch you need, people want to know how much the winch should be able to pull. Ideally, a good trailer winch should be able to pull the gross weight of cargo multiplied by 1.5. So, if you want to pull a 5,000-pound boat onto the trailer, you will need a winch with a 7,500-pound load capacity.

5,000 lbs x 1.5 = 7,500 lbs

Load capacity is arguably the most critical aspect of winch size. It determines which tasks and loads your winch can handle safely. But even though a winch with a 5,000 lbs capacity is designed to pull 5,000 lbs, I do not recommend using it at full capacity.

Why Size Matters For A Car Trailer Winch?


The size of a car trailer winch is crucial for its effectiveness, safety, and your own comfort. A properly sized winch can perform its tasks more efficiently. Remember that an oversized winch also consumes more power to compensate for its size and weight.

That's not ideal, but undersizing is much more detrimental to both your winch and the tasks it's meant to perform. An undersized winch can lead to very costly mistakes. For instance, if you try to pull a 6,000 lbs load with a winch rated for 5,000 lbs, it can snap, releasing the cargo.

An overloaded winch can burn out, snap, and potentially injure people standing nearby. It's not safe to play with the load capacity of your winch, so please pay attention when choosing the right size. Such failures can pose a serious risk to property and individuals nearby.

The same goes for using your trailer winch at full load capacity. If you frequently pull at its limit, the components of your trailer winch will wear out quickly. It's recommended to choose a winch with a size (or load capacity) that comfortably exceeds your expected needs.

3 Tips To Choose The Right Size Winch For A Car Trailer

Choosing the right size winch for your car trailer requires practical considerations and foresight about the loads you expect to haul. Here are the three most important things to consider: 

  1. You should determine your maximum load. Calculate the heaviest load you anticipate hauling or lifting onto the trailer. 
  2. Follow the simple and trusty 1.5 rule. As a general guideline, your winch should be rated at least 1.5 times the maximum single load you expect to pull. You can go a little more than that, just in case. If, in the future, you can see yourself hauling something heavier or hauling more often, it's worth it. 
  3. Look into winches that come with additional performance accessories. These extra parts, like snatch blocks, for instance, can effectively double the pulling power if your winch can handle that much extra strain. Protective covers and mounting hardware can increase the service life of your winch.

What Size Winch Do I Need For My Car Trailer?


Determining the correct size of a car trailer winch is not rocket science. All you need are just a few tips on what to look for.

First, you need to consider the heaviest load you anticipate pulling with the trailer winch. Take that number, round it up, and then multiply by 1.5. That's the approximate load capacity for your ideal winch.

Of course, pulling at full capacity is not a good idea. So you should add just a little extra weight for the future. But don't add too much, as it will decrease performance.

Another interesting thing to consider is how your winch actually works and how it impacts capacity and performance. Winches pull the most weight when there's only one layer of rope around the drum. As more layers of rope are wound onto the drum, the pulling power decreases.

This is when drum size and rope width and length begin to matter. Up until now, we were only talking about load capacity in terms of size. But the actual physical size of the winch itself also matters in this context.

Can You Have A Winch On A Car Trailer?

When the topic of winches is brought up, it usually revolves around off-roading, trucks, and vehicle recovery. However, a trailer winch can be a very useful tool for loading and unloading vehicles like boats, snowmobiles, jet skis, and so on. It is also excellent for getting different heavy cargo on and off the trailer.

Depending on where you decide to mount the winch, it can perform various tasks. If you install it at the front of your car, it serves as a powerful means of vehicle recovery. But if you mount it onto the trailer, it can assist with pulling whatever you want onto the trailer and unloading it in a safer and hassle-free manner.

What's The Best Winch For A Car Trailer?

The best winch for your vehicle will depend on your needs. Remember that size indicates how much you can pull with the winch. If one of the popular winch models meets your load capacity requirements, it might be a good place to start your search.

5 Best Trailer Winches



Load capacity


Warn Zeon 10-S

Synthetic rope for safety

Corrosion-resistant finish

Renowned for reliability and build quality

10,000 lb

$1 450,00

Superwinch Terra Series

Compact design and versatile

Suitable for utility tasks and ATV/UTV

2,500 to 4,500 lbs


Smittybilt X2O

Waterproof winch with wireless remote

Suited for various trailers

10,000 to 17,500 lbs


Mile Marker SEC8 (ES)


Electric and waterproof

8,000 lb


Badland ZXR12000

Affordable without sacrificing power 

Wired remote control and automatic load-holding brake

12,000 lb


How Do I Choose A Trailer Winch?

If you're looking for something that can help you with vehicle recovery, the load capacity will depend on the GVWR of the vehicle. Such winches are extremely powerful and durable, but they also have downsides.

The sheer size and weight of components for a winch that can handle recovering a Jeep out of a maze of thick mud can impress anyone. But this demonstration of strength also comes with a major drawback: the winch requires a lot more power to work properly.

It also makes your vehicle heavier at the front. This may throw off the weight balance a bit. And it also makes your vehicle heavier in general.

Car trailer winches, on the other hand, are smaller but are no less impressive. Their main purpose is to load cargo or RVs onto the trailer. Their size will depend on the weight you expect to pull or lift with the winch.

How Do You Calculate Winch Size?

To calculate the size of your winch, you should first find out the Gross Vehicle Weight Rating (GVWR) of the vehicle you want to pull with the winch. GVWR is the vehicle's total weight, including all cargo, equipment, the winch itself, passengers, fuel, etc.

If it's not the vehicle but cargo instead, aim for the heaviest cargo you expect to pull or lift.

As you already know, the next step is multiplying the weight by 1.5. This will give you the approximate load rating of the winch you are looking for. A safe bet would be to get a winch with a higher load capacity, just don't overdo it

For example, if your vehicle has a GVWR of 4,000 lbs:

Required Winch Capacity = 4,000 lbs (GVWR) × 1.5 = 6,000 lbs

You should buy a winch with at least 6,000 lbs load capacity. Ideally, a little more than that, like 6,500 lbs or 7,500 lbs.

What Diameter Is A Winch For A Car Trailer?


The diameter usually references one of two parts of a winch. The first one is the drum. Its diameter is typically connected to the pulling capacity.

High-capacity winches usually have larger drum diameters. This is because larger drums can accommodate thicker cables. They are sturdier and also provide enough space for the cable to wrap around the drum without forming a second layer, which would decrease performance.

For example, smaller winches designed for ATVs might have drum diameters around 2 inches, while larger winches designed for trucks or trailers might have drum diameters of 2.5 to 3.5 inches or more.

The cable or rope thickness is also very important to consider. Essentially, the bigger the load capacity, the thicker the cables. It's unavoidable because the rope will have to withstand tremendous strain from the load.

Can You Have Too Big Of A Winch?

Yes, a winch can be too big for what you plan to do with it. It's not necessarily bad for you, but there are a few issues that can be avoided with the correct size of a winch.

First of all, bigger winches are heavier. The weight influences the careful balance of weight distribution throughout the trailer.

And secondly, they consume too much power for simpler tasks like lifting significantly smaller loads than they are designed for.

And they also cost a lot more. So, why pay more?

Can You Have Too Small Of A Winch?

Unfortunately, a winch can be too small. If you don’t apply the 1.5 rule or apply it incorrectly, you can end up with insufficient load capacity.

Don’t pull at full capacity, and certainly never overload your winch. It’s too dangerous for both cargo and people around. The rope can snap from strain or wear at any moment.

The best way to avoid this problem is to choose a winch that can pull slightly more than you think you need. An extra 500 or 1,000 pounds can make a significant difference, but not in the price of a winch.

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