Last Updated: 10.12.2020

The spark plug is an essential component in the engine of a gas engine. And when the time comes to replace the existing/faulty ones with new plugs, it can be a dilemma — whether to stick to the same ones as before or upgrade. And if you choose the latter, will the upgrade actually be an upgrade in terms of how the vehicle performs? Are there any specific things you must be looking for when switching brands? In essence, how to choose the right spark plugs for your car or truck. We try to find relevant answers in this feature here.

Know the Spec

First of all, it’s imperative that you find the exact specifications of the spark plugs in your car/truck. Since you’ll need to refer to official documents for this, we’d suggest sticking to the manufacturer-supplied user’s manual for the same. If you can’t get hold of that, try checking with the official dealer about the specs. Auto-part stores can also help with the specs, but the most trustworthy source will always be the manufacturer-sourced info. 

In the user’s manual, you’ll find information like hex size, seat, thread size, and even thread reach. Then you’ll find some more specs of the ideal spark plug that can be fitted to your vehicle. For example, apart from the aforementioned, it will also have details on the electrode gap (as specified by the carmaker), and also the recommended brand and make of the spark plug. With these, it becomes easy to find the set of plugs that perfectly fit your vehicle — and help the engine work optimally.

Which Brand?

Talking about brands, do you stick to the one recommended by the manufacturer, or do you move away from that? There are two ways of handling this conundrum. If you want the same performance and longevity as the plugs that came with your car or truck (that’s assuming the vehicle was supplied with the same ones as recommended), then you can go this route. This could for a lot of users be the safe choice, but the point is as long as you’re sticking close to the manufacturer recommendations (in terms of specs), most reputed plugs are going to be alright.

And that’s why you should look at the other alternatives out there. Apart from a different brand, you must wonder if there’s any other difference. That’s a fair point to contemplate because there’s a lot that you can benefit from. Here are a few ways in which you can upgrade from the standard set of plugs. 

The type of electrode, for instance, is one such area where spark plugs have evolved. Some spark plugs can come with multiple ground electrodes. Manufacturers claim that with this, the plug is bound to be more durable than the vanilla choices. You can take a look at the various types of spark plugs available for Chevrolet Silverado 5.3 in our guide here.

Tip Material

Another aspect that you must look at when upgrading your vehicle’s spark plugs is the tip material. A lot of good brands also offer spark plugs with Platinum or Iridium tips. These make it easier on the electrical system to cause the combustion (since platinum requires less effort for ignition — and iridium less so). But more importantly, these are said to be much more durable than the conventional spark plugs. So these are bound to last much longer — iridium theoretically should last the longest.

This should make sense to those who have high-performance engines or want to save up on the labor cost that changing plugs more frequently can incur. Or even if they do it all by themselves, if the plug location is difficult to reach and is thus a time-consuming process, owners can opt for platinum or iridium plugs that offer a longer overall life. This does come with a downside, as both platinum and iridium plugs are more expensive — iridium ones are the most expensive among these. Despite that, the savings you’re going to make over labor costs will be substantial. Some owners do suggest sticking to the conventional/nickel ones in older engines in case they burn oil. Because while the nickel ones can stand oil, these more expensive ones might not be able to handle that.

Hot or Cold?

And lastly, which plug should you buy: hot or cold? What’s that, you may ask. That’s another way of differentiating standard plugs from those required in ultra-high-performance vehicles. A hot plug is what most vehicles get in their standard spec. It’s made in a way that the center electrode stays hot and burns off residue — and thus minimizes the chances of misfires. A high-performance vehicle requires a cold plug. These will dissipate heat quickly — which is necessary especially in the case of engines that are working extra hard. Sticking close to the manufacturer-recommended heat range is a great choice for stock engines. For highly modified ones, cold plugs are recommended.

It’s best to stick with popular brands, not just for the overall quality alone but also for the warranty and overall after-sales service. NGK and Bosch are two of the highly trusted brands — and these offer a variety of plugs. From standard ones, intermediate platinum plugs, to the iridium plugs, there’s something for everyone. Some strong stock replacement ones come from ACDelco and NGK. You can check these out as well, especially if you want to stick to the ones that are recommended by the manufacturer.

Our Last Tip

If you’re planning to pick these from an online marketplace like Amazon, refrain from picking individual packs. These turn out to be costlier, and if a plug turns out to be faulty, it might be difficult to return, because depending on your car or truck, you would’ve ordered multiple of these. A single pack of four, six, eight, or ten might make more sense. Do keep an eye on warranty and whether the plugs are pre-gapped. Because the spark plug gap is as important as the plug itself.