A winch is a basic mechanical tool to lift weights conveniently without putting in much physical labor and effort.
A trailer vehicle is incomplete without mounting a winch. Some main applications include loading and unloading the vehicle onto a trailer, pulling out the vehicles from difficult terrain.
The winch pull capacities depend upon the weight of your vehicle and the slope you are pulling it up to.
Let’s discuss the factors that affect the pulling capacity of a winch.
How Much Weight Can a Winch Pull?
We can divide the use case of winches into two case scenarios. Firstly, vehicle recovery. Secondly, loading and unloading off trailers.
1. Vehicle Recovery and Winch Capacity
In the first scenario, if you want to recover a vehicle stuck in different terrain, then, in that case, the suitable winch capacity is totally dependent on the gross weight of the vehicle.
Gross weight means the curb weight of the vehicle plus the weight of accessories and passengers on it.
In this case, the required winch should be rated 1.5 times the gross weight of the vehicle.
Recommended Winch = 1.5 x Gross Weight of the vehicle
For instance, let’s say the gross weight of your vehicle is 3,000 lbs. Then to pull it out, you need a winch of rating 4,500 lbs. (1.5 x 3,000 = 4,500 lbs.).
Another quite important factor is that the rated capacity mentioned on the winch is only applicable for the first two layers of the rope.
The first layer means when all of the winch cables are off the drum except the first layer.
At the first or second layer, the winch can operate at its rated capacity, let’s say if that is 3000 lbs.
But if two or three layers are wrapped around the drum, the winch capacity drops significantly, about 10 to 12%. For instance, the pulling capacity of 3000 lbs. winch reduces to 2430 lbs. if three layers are wound around the drum.
2. Trailer Winch Capacity
Another case scenario is the use of a winch to pull a vehicle on a trailer. Since in this case, the vehicle moves on its wheels, this kind of vehicle is termed as the rolling load.
In comparison to the static loads, as discussed in the first case, the rolling loads are much easier to pull. In this scenario, the winch can pull much higher than its rated capacity but this capacity is dependent on the slope of the trailer.
To determine the capacity of the winch required, you need to know the slope and gross weight of the vehicle.
Then, using the following table, you can determine the Rate Line Pull (RLP) of the winch. RLP is the maximum weight winch can pull perpendicular to the ground.
Following table gives you an overview of how big of a winch you need when pulling up car on a trailer:
|Rated Line Pull
|10 %||20 %||40 %||60 %||80 %||100 %|
|1000 lbs.||5025 lbs.||3401 lbs.||2155 lbs.||1664 lbs.||1422 lbs.||1285 lbs.|
|1500 lbs.||7538 lbs.||5102 lbs.||3233 lbs.||2496 lbs.||2134 lbs.||1928 lbs.|
|2000 lbs.||10050 lbs.||6803 lbs.||4308 lbs.||3331 lbs.||2845 lbs.||2175 lbs.|
|2500 lbs.||12563 lbs.||8503 lbs.||5388 lbs.||4160 lbs.||3556 lbs.||3213 lbs.|
|3000 lbs.||15075 lbs.||10251 lbs.||6428 lbs.||4991 lbs.||4268 lbs.||3854 lbs.|
|3500 lbs.||17588 lbs.||11905 lbs.||7543 lbs.||5824 lbs.||4979 lbs.||4499 lbs.|
|4000 lbs.||20100 lbs.||13597 lbs.||8643 lbs.||6655 lbs.||5690 lbs.||5138 lbs.|
|4500 lbs.||22613 lbs.||15306 lbs.||9698 lbs.||7488 lbs.||6401 lbs.||5784 lbs.|
|5000 lbs.||25126 lbs.||17009 lbs.||10776 lbs.||8320 lbs.||7112 lbs.||6427 lbs.|
In the table, first, look in the slope column and find the gross weight in that column. Corresponding to that weight, you can determine the rated line pull. You can use the winch of this rated capacity for your vehicle. Slope percentage means the height of the slope divided by its length.
Recommended: How to wire a winch without a solenoid?
Will a 2500 lbs. winch pull a car on a trailer?
The simple answer is yes, a winch with a rated capacity of 2500 lbs. can pull a rolling load of 12,563 lbs at 10% inclination. An average car weighs around 4,146 lbs. So that means, you can easily pull up a car on a trailer using this winch.
A 2500 lb. winch cannot pull a car stuck in mud or any difficult situation, because the gross weight of an average car is much higher than 2500 lb. In that case, it can only pull around 1250 to 1500 lbs. Check out the best winches specifically for car trailers!
On the other hand, the same winch can safely pull up a car weighing up to 12,000 lbs. on a trailer with a slope ranging from 10% to 40%. Beyond that slope, you will need a higher-rated winch.
Now, the difference in both cases of the static load and rolling load. In the first case, the car is stuck, and it needs a lot of power to pull. In comparison, while pulling over the rolling load is quite easier to pull since the is on its wheels. That is why a winch can pull a rolling load more than its rated capacity.
Despite the mathematical calculations, it suggested for safety concerns that you buy a winch which slightly (1.5 times) the rated line pull.
Will 3000 lbs. winch pull a car on a trailer?
A winch with rated capacity of 3000 lbs. can easily pull a rolling load of 15075 lbs. at 10% inclination. Even at 100% inclination it can pull ~4500 lbs which is more than the weight of an average car which is around 4200 lbs.
Since the 2500 lbs. can safely pull up a car, then probably the 3000 lbs. winch can also do the same job.
Remember that if the car is stuck in some difficult terrain or mud, this winch cannot pull it out. For that, you will need a winch that is rated 1.5 times the gross weight of the vehicle that is to be pulled.
How we can enhance the pulling capacity of the winch?
You can enhance the pulling capacity of a winch by adding a pulley block which can almost double the winch pulling capacity. The pulley block lets you add more layers of the winch which significantly makes the winch to work at higher capacities.
Now, if you face a situation during off-roading when your car stucks in mud or pit. And you need a high-rated winch that is not present at the moment. Then, adding an attachment can also increase the pulling capacity of the winch.
I hope that your query regarding the pulling capacity has been resolved and you have understood how you can determine which winch is suitable for your trailer.