Motor Vehicle Maintenance & Repair Stack Exchange is a question and answer site for mechanics and DIY enthusiast owners of cars, trucks, and motorcycles. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I recently bought a used car, and it didn't come with any jumper cables, so I'm going to buy some. I briefly looked around at a store and online, and there seems to be a wide variety of prices and specifications. These are the particular specs I've seen variation in:

  • Length of cables
  • Gauge (thickness) of wire
  • Material of clip
  • Type of insulation

Are there any significant practical differences between different materials used in jumper cables? How can I determine what gauge wire I need? Is there anything else I should consider when selecting a set?

Note: I'm not looking for specific recommendations, I'm just trying to get a sense for what types of specs I should look at and how I can determine what specs are needed for a particular vehicle.

share|improve this question
    
This helps slot. I was going to get one of the cigerette lighter deals. I noticed that they are saying it would take a long time to help. That's because its not jumping it, its charging it. So its not what I want. Thanks!! – user12151 Sep 10 '15 at 14:41

The biggest thing to look at for me is the gauge of the wire. The reason I bring this up is, the higher the gauge (numerically) the thinner the wire. Thinner wire will require your jump-start procedure to take more time, as it takes a while to charge the battery before you'll have enough juice to get it running. Thinner wire cannot pass enough amperage to start a vehicle. You'll find when trying to jump another car, the wire can get warm during the attempt. This is because it's trying to pass more juice than the wire can handle. With thicker wires you can actually start the vehicle directly from the running vehicle with little to no wait time.

You will also find that the larger gauge (lower number numerically) will have longer cable lengths, which will allow you to go battery-to-battery more easily in more and varied situations. I bought a set of 2-gauge cables over 20 years ago which continue to service me today. They are about 20' long, which gets me from battery-to-battery very easily.

While the cost of cables goes up as the wire gets thicker, you'll also notice the quality of clamps get better as well. Cheap wires have cheap clamps, which are a pain-in-the-butt to use as well as they are less likely to stand up to time. Cheap clamps are copper plated. Better clamps will be solid copper, which will transmit electricity much better. After utilizing a plated set a few time, the copper can be worn off down to the steel substrate, which does not transmit the electricity nearly as well, meaning your cables won't work very well.

Insulation is no different as to the gauge of wire. The thicker wire, the better the insulation. If you live in a cold climate, cheaper insulation will usually crack very easily. Better insulation will retain its pliability while you uncoil and recoil it during/after use. Cheap insulation will not want to straighten out, making them very hard to use.

Needless to say, jumper cables are one of those purchases where you get what you pay for ... don't skimp out on them and you will never regret it.

share|improve this answer
    
Thanks for the advice. I'm seeing cables ranging from 2 - 12 gauge... would you always go with a 2-gauge cable regardless of the vehicle? – nhinkle Jun 11 '14 at 17:35
    
@nhinkle ... That's what I use and carry all the time. It is my opinion that you should go large or go home. I am an impatient person. I hate to wait while the dead battery is charging before I can start the vehicle. With 2-gauge cables you are always in good shape. As long as your clamps can get good connectivity, you can most of the time do a straight jump and get the opposite vehicle going with little or no wait time. You cannot do this with 12-gauge jumpers. – Pᴀᴜʟsᴛᴇʀ2 Jun 11 '14 at 18:09
    
So I'm finally getting around to actually figuring out which ones to buy, and I'm finding that a lot of jumper cables seem to be "copper plated aluminum" instead of plain copper, even on some that seem (to me) to be pretty expensive. Am I correct in inferring that I should avoid aluminum cables and try to find some that are actual copper? – nhinkle Jul 12 '14 at 18:10
    
@nhinkle ... get what you can afford. You want copper wire. You may not be able to find anything but copper coated aluminum clamps, so get what you can get. If you look at them, you'll be able to tell flimsy clamps from sturdy ones. The sturdy ones usually come on the wires which have a larger gauge wire (remember, the lower the number, the higher the gauge, ie: 2-gauge is larger than 6-gauge). – Pᴀᴜʟsᴛᴇʀ2 Jul 12 '14 at 18:13

As someone who up until recently was relying quite heavily on Jumper cables due to a bad battery and lack of funds to replace it, I have to emphasise the following:

Length:

The jumper cables were cheapo specials I bought in a supermarket, and were only just long enough for me to get the battery connected to the "jump" car if they were literally bumper to bumper. Longer ones are better, simply because you don't need to do this. Pushing a dead car off the drive in freezing rain is no fun, particularly if you then have to spend a further 5-10 mins in the rain fiddling with the connections to make them work!

Gauge:

As already noted by others, the lower the gauge, the less time you'll spend waiting for your battery to be ready. Vital in winter. Might save whoever you're having to jump off a little petrol and time too.

Safety Grips:

If, like me, you're constantly having to jump the car, or conversely you're doing it for the first time having had little sleep and in the dark, you may accidentally do what I did one cold morning and cross the cables.

This is not advised for several reasons, least of which is the speed at which the metal clamps heat up. Thankfully I was protected from a major shock by the rapidly melting insulation on the actual clamps.

Additionally, as it was just a borrowed oversized battery I was jumping off I didn't risk anyone or anything else other than myself and my car with my idiocy.

Unfortunately, as the insulation was melting, I still got a shock and additionally a very nasty burn to my hand for my trouble. I'd definitely recommend completely skipping anything with shrink-wrap style insulation and go for something with a fully plastic handle surrounding the clamps, or something with very thick insulation on the handles. You'll thank me if you ever do something stupid with them, like I did.

share|improve this answer

Remember, you usually use jumper cables at the most INAPPROPRIATE times, in the freezing cold, at night, or in the rain. Dont skimp on this important piece of safety equipment. Dont go less than 4 gauge. The last thing you want to be doing is waiting in these conditions for the battery to charge up enough to start. Dont ask me how i know!

share|improve this answer
    
Good call. It's also worth noting that the higher the gauge, the lower the number will be numerically (2 gauge is greater than 4 gauge ... for the uninitiated). – Pᴀᴜʟsᴛᴇʀ2 Jun 10 '15 at 1:34

It doesn't really matter all that much. The more expensive cables will probably last longer, but unless you plan on keeping the car for more than 10 years, I'd just go with the second cheapest set. My own personal rule of thumb being that the second-cheapest option of anything is usually the best value for money. The cheapest one will break and the most expensive one will not be so much better that it justifies the extra money.

share|improve this answer
1  
...and this applies to everything in life – Murtaza Mandvi Mar 10 at 20:39

I know this post has been around a while, so I will just add some useful info for anyone that is thinking about getting some jumper cables.

first, what I recommend is at lease 4 gauge, 20 foot, or better jumper cables. If you have the money, try to get all copper wire jumper cables. If you don't have the money for all copper, then get at least 2 gauge cables. The reason I say this, most jumper cables sold now, especially the cheaper ones, ane what they call copper clad. What that means is, the jumper cables are made out of an aluminum cable/wire, with a very thin, copper coating on the outside. More then 99% of the wire is aluminum. Because of this, a 4 gauge all copper wire will give about the same amps as a 2 gauge copper clad aluminum wire.

The other reason why the all copper wires are better is because the all copper ones are more durable then the copper clad versions. While I am in no way saying that the copper clad version is not durable at all, the aluminum in it can corrode over time, where this is less likely to happen with the all copper ones.

The reasons that I say to get at least 4 gauge is this. Once a vehicle is started, the alternator should produce enough power to keep the vehicle running, no matter what kind of condition the battery is in. If you get a vehicle that the battery is just about completely dead, or does not hold much of a charge, the 4 gauge ones should be able to get that vehicle started with no problem, and then the alternator should continue to charge the battery, along with keep the vehicle running. But if you use some cheap 10 or 12 gauge cables, you will have to wait a while for the battery to charge up enough to start the vehicle, before it will start. Those thin jumper cables will add very little power to what is in the vehicle, so you have to have the power charged up in the battery to get it started. If that battery does not hold a charge, then the thin, cheap, 10 or 12 gauge ones, will never be able to get the other vehicle started because they can not transfer enough amps to get it started. So you will want something that will be able to get the vehicle started, no matter the condition of the battery.

And as other have stated, the 20 foot length should give you plenty of length to get to the battery on both vehicles. You never want to be stuck in a position where you have to push a vehicle, and move it, just so you can get another vehicle close enough to jump it. This can especially be problematic if you are on a hill, or in the snow, etc.

As for any of those jumper boxes that plug into your cigarette lighter. Those will only be good if you have a slightly low battery, and have plenty of time to wait for the power to be transferred from the box to the battery. Also, dont forget, if you have to turn your ignition key to the on position to get that socket to work, that also means that you are going to waste a lot of that power, to power the stuff in the car when the switch is turned on. Those type of jumpers, while good for a slightly low battery, and if have the time (which can be a good 20 minutes or more). But, if your battery is, say half dead, or more, then those types will never give your battery enough power to get it started.

Think of it this way. Most regular jump starters, whether it be one that you connect straight to the battery, or though the cigarette lighter socket in the car, all have what they call SLA batteries in them. What this is, is basically, the same exact type of battery that is in your car, but in a spill proof container. SLA stands for, sealed lead acid. Now take into consideration that the battery is also in a carrying case with lots of plastic around it too, plus any circuitry, etc. Now compare that to the size of your battery in the vehicle. It (the jumper) is many times smaller, which just goes to show you, just how little they have in power. If you need numbers, some of those jumpers can hold as little as 7ah of power.. while a small car battery will start at around 50ah of power. The higher the number, the more power it can store. That means, a vehicles car battery can be 7 times more powerful, and can around as much as 14 times more powerful for larger vehicle. This is why they can be useful, but also is very limited too.

This is also the reason why, you can not rely on them, if your car battery is too dead too. This is a good reason why, you will not be able to replace a good set of jumper cables with a cheap jumper box. and with jumper cables, as long as you have a vehicle there that is running, you have an, almost, unlimited source of power. But jumper boxes.. Once the battery is dead, it is useless until you spend a few hours recharging it. Not to mention, because it is a battery in it, the jumper boxes, are only good as long as the battery is good too. You accidentally hit the button and turn the light on.. Don't notice it.. guess what.. When you go to use it, that jumper box is going to be dead.

In the end, while jumper boxes do have their uses, as do cheap/thin jumper cables, you really can not replace a good set of jumper cables with either of them. At the least, you should have a good set.. and if you still want the jumper box, get that in addition to the jumper cables.

share|improve this answer

protected by Community Dec 6 '15 at 22:16

Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.