Jumper cables are also known as booster cables. It is important not to buy cheap, low quality jumper cables because it could potentially be dangerous for some car batteries. The main difference between cheap jumper cables and good quality jumper cables is the resistance. Good cables will be thick with the least resistance possible. The more resistance there is in a cable, the more heat that is generated and less energy is transferred which might not start the car, especially in colder conditions.
Cheaper, poorer quality jumper cables will add resistance that might prevent you from jumping your vehicle properly. They are also likely to be shorter which may cause it to be difficult to connect your battery to another vehicle’s battery. Extended poor quality jumper cables will also increase your chance of failure and add more resistance to the connection. Another big no-no is to connect two jumper cables together so that they will connect the batteries.
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What happens when your battery dies?
Very few people actually know and understand how their car batteries work and what happens when we jumpstart the battery. We must first begin with the basics. Car batteries consist of 6 lead acid batteries with each providing a standard charge of 2.1 volts. This means that the total voltage of your car battery is about 12.6 volts or higher.
When the vehicle is running the alternator will raise the voltage between about 13.5 volts to 14.5 volts which will charge your car battery. Depending on the age and size of your car battery, if the charge drops below 12 volts you’ll have problems starting your vehicle. When your vehicle dies and won’t start, you use jumper cables to connect to another vehicle’s alternator to boost your voltage high enough to charge the battery.
Depending on the quality of jumper cable you use, the amount of resistance between your power source and your vehicle’s dead battery will vary substantially. If a car battery has become deeply discharged it will be more difficult to jumpstart. A higher quality cable with less resistance will increase your chances of success. A battery becomes more deeply discharged the colder the weather and the longer it has sat unused. This is especially a problem if you leave your car lights on which can drain your battery very quickly.
What we look for in jumper cables
Gauge: This is a number that specifically relates to the diameter and thickness of the wires inside. A standard set will have a wire gauge of 6. The lower the number, the greater the diameter and thickness of the cables which will provide a faster charge. This means a lower gauge rating generally indicates better quality and durability. Jumper cables with a gauge rating of 8 will still be able to jumpstart most vehicles, but it is better to have at least a 6. Larger vehicles and larger batteries will require more power and will usually need cables with a gauge rating of 6, 4 or even 2.
Thickness: A thicker cable is more durable but it will be heavier. Most brands will label their jumper cables as ‘heavy-duty’ and you’ll occasionally see some that say ‘light-duty’. It is always better to check the actual thickness and wire gauge before purchasing.
Material: The majority of jumper cables are constructed of copper clad aluminum (CCA). Pure copper is the best. Aluminum is about half as conductive as copper.
Clamps: These are attached directly to the batteries of the vehicles involved. It is important that the teeth are strong enough to stay attached to the battery terminals and have comfortable rubber handles for safety. Good clamps will be pure copper have well-insulated grips. The crimp should also be high quality as it is anothe
r resistance point.
Length: Jumper cables won’t work if they can’t reach the battery of another car. Make sure the cables provide enough length to reach another car. We suggest a minimum of 12 feet. Avoid buying really long cheap cables because this will add a lot of resistance to the connection.
Insulation: Most brands have heavy-duty insulation within their jumper cables. This helps reduce energy loss (heat) and lowers resistance. Poor quality cables will have less insulation and increase resistance. The next time you are jumpstarting a vehicle, try touching the outside of the cables and you’ll most likely feel a radiating heat, which is wasted energy.
Price: More expensive jumper cables provide more peace of mind, its as simple as that. You’ll have a higher success of boosting larger vehicles in harsher and colder weather. A good quality set of cables will last forever and make those times when your battery is dead, less of a headache. Cheaper jumper cables are also more likely to be smaller, shorter and lighter.
Best 6 gauge jumper cables
For any standard passenger vehicle, we recommend the 6 gauge Iron Forge Tools 20 foot jumper cables. These are 400 AMP, 6 gauge, high quality, all-weather jumper cables that provide the best value for the price. Most people will not need better jumper cables than this unless you’re dealing with very cold weather or large trucks. We prefer the 20 foot length because most cars are on average about 15 feet. The generous 20 foot length allows for a car to park behind and still let you reach both car batteries. You never know when you’ll need that extra length. We also really liked these cables because of how strong and sturdy they are. The clamps are provide a powerful grip and the cables are thick. The provided carrying case also helps the cables stay neat in your trunk or wherever you choose to store them.
One of the most popular jumper cables on the market is the Cartman 6 gauge booster cables. However we had issue with these jumper cables because they feel more like 8 gauge. We found very little actual copper and the resistance to be too high for the claimed wire gauge. Quality control also appears to be a big problem and these jumper cables have been found to fail far too often. This is surprising due to how many good reviews for this product out there, but this is likely because many people probably haven’t actually used the jumper cables yet. These cables are quite cheap and the quality control reflects that.
Best 4 gauge jumper cables
For trucks, vans and SUVs that have larger batteries (still works great for normal cars) we would go with the 4 gauge Performance Tool (W1673) jumper cable. These are heavy duty 600 AMP, 20 foot jumper cables that really impress for the price. We really liked this pair because of the strong copper clamps, high quality construction, true 4 gauge cable internal cable diameter and tough, durable cable sheathing. These are a little more expensive than the 6 gauge but are a great long-term investment for any truck or larger vehicle. They are absolutely worth for any vehicle with a larger battery and if you will be dealing with cold-weather conditions regularly. The 20 foot length also lets you park behind most vehicles and still reach the batteries. The cables are flexible and long so you shouldn’t have any problems.
There are a couple 4 gauge alternatives such as the OxGord 4 gauge jumper cable and the Cartman 4 Gauge jumper cable which are both decent, but again we have seen quality control and reliability issues. There are also concerns that the internal wire diameter is actually 6 gauge from both brands and not the claimed 4 gauge. Still these are the best alternatives we found to our top pick and you’ll likely be happy with these, we just don’t have faith in a consistent high quality product from them.
Best 2 gauge jumper cables
We found the best heavy duty, 2 gauge jumper cables to be the Energizer 2-gauge 800 AMP ENB-220. These are part of the Energizer professional series for all types of vehicles including full size trucks, SUVs, tractors, buses and RVs. We absolutely love the heavy duty well-insulated copper clamps. They have a strong, tight grip and are designed so that the clamps will never spark each other if they touch. This also helps reduce the chance of an accident happening with the engine. The cables have a true 2 gauge internal wire diameter with copper clad aluminum. The tangle-free booster cables are also still flexible and functional even down to -40°C temperatures and are suitable for both top and side posts. For the price these cables are unbeatable for commercial level quality. These are the pair of jumper cables you wish you’ll have had during the next blizzard or storm.
The Performance Tool (W1669) 20 foot 2-gauge jumper cable is a fantastic alternative to the Energizer heavy duty jumper cables. These are similar commercial duty, all-weather cables that are comparable in terms of quality and thickness. The cables have a nice rubber feel and strong, tight clamps with the same parrot clamp style design. You’ll be very happy with these.
For the sake of completeness, another alternative is the ABN 2 gauge commercial grade jumper cables. These are decent quality, heavy duty cables but they are cheaper for a reason. The sheathing feels more like plastic than rubber with a slicker feeling. These are also 600 AMP, not 800 AMP compared to other 2 gauge commercial jumpers. Our biggest problem however is that the clamps while appearing heavy duty, there is not nearly enough spring tension. This is a problem because weak clamps will result in less power being transferred during usage. Therefore we consider these unsuitable and too inconsistent for commercial use.
Best 1 gauge jumper cables
As with the 2 gauge version, the Energizer 1-Gauge 800A heavy duty jumper cables are part of the Energizer professional series for all types of vehicles including full size trucks, SUVs, tractors, buses and RVs. These will power up your dead batteries faster and are tougher than any other jumper cables we could find, and they are the only way to go if you have a V8 or diesel. For commercial, heavy duty hardware, these have exceptional quality and will withstand daily cold-weather conditions and heavy abuse. They are also 25 feet, 5 feet longer than the 2 gauge version which is already long. This is particularly important for full size trucks and RVs when there can be issues with getting up close. The only concern with these cables is that the copper clamps might be a little too strong, but at least you’ll never be worried about them detaching. For normal passenger vehicles these are definitely overkill, but for any commercial vehicle these are the best jumper cables you can buy and are certainly buy-it-for-life.
Best motorcycle jumper cables
For a motorcycle you need a pair of jumper cables that are lighter and shorter but still thick and durable enough to deal with all-weather conditions and regular use. We recommend going with the 8 gauge, 8 foot Yuasa YUA00ACC07 jumper cables. These are tough enough to withstand freezing temperatures and light and compact enough to take on long trips. They also have smaller clamps that are easier to connect to your battery terminals in tight spots or weird angles. Afterwards they wrap up nice and small into the bag that it comes with. Highly recommended and great for fast and easy jumpstarts.
How to use jumper cables
Jumping a car battery is a rather simple set of steps:
Line up two cars so that the hood (front) is close enough for the jumper cables to connect. Make sure the vehicles are not touching each other and both car engines are turned off.
Open the hoods and prop it open.
Clamp one jumper cable (red or black) to to the positive (+) terminal of the dead car battery.
Clamp the other end of the SAME color jumper cable (the same color in step 3) to the positive (+) terminal of the working car battery.
Clamp the remaining jumper cable (opposite color used in steps 3 and 4) to the negative (-) terminal on the dead car battery.
Clamp the other end of the same color and cable to the negative (-) terminal on the working car battery.
Confirm that the jumper cables are only touching the battery terminals and nothing else.
Start the engine of the vehicle.
Start the engine of the dead vehicle and keep it running to charge the battery.
Disconnect the jumper cables.
Bonus jumper cable tips
If you are still having trouble boosting the vehicle especially in very cold weather try these tips:
Clean the battery terminals of any acid.
Leave the working vehicle connected and run its engine for several minutes before trying to start the dead vehicle. For difficult cases leave the engine running for up to ten minutes. Patience is important here.
Let the car being jumped stay running for a while to make sure the its battery properly charges so you don’t have to jump it again the next time you shut it off (should be common sense).
Turn off all electronics in the dead vehicle including the radio, headlights, AC/heater and anything in the cigarette lighter or USB connections.
If you are still having issues, rev the engine of the working vehicle while it’s connected with jumper cables (make sure the vehicle is in park with the handbrake on). This will allow the alternator to provide a full current and reduce charging time. You can also try revving the engine of the working vehicle while turning the key in the dead vehicle.