5 Auto Tools Mechanics Say Are Not Worth Buying

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As a DIY mechanic, it’s easy to get sold on auto tools. That’s because the industry knows you want to have something in your toolkit for almost every problem that might come up so it tries to push as many tools as you have to have. And in the meantime, it often sounds like a good idea. But after collecting a bunch of these tools, you start to realize that you rarely have access to some of them, which is a shame, because many of these special tools are not cheap.

Sometimes, you already have a tool for the job. Sometimes, they’re not as flexible as you’d expect, and you might be better off with something for more purposes. In some cases, these tools come from a professional shop and have no business in a home garage. That’s why it’s important to know where to spend when building a toolkit.

So we’ve searched to see what mechanics and enthusiasts have bought, tested, shelved, and finally taken out of their tool kits. If any of these are tools you’re considering right now, you might want to think twice about adding them to cart. Because they are more likely to waste money. If you are ever in a situation where you really need some of these tools, your car probably needs to be serviced by a professional mechanic. Ultimately, that’s money that would be better spent using useful tools that you’ll reach for over and over again.

Engine parts in modern cars are tight, tight spaces, and a standard wrench may not have the necessary clearance to do its job. Moon wrenches, also called half-moon or S-wrenches, were designed with that problem in mind. Its curved shape is meant to reach awkward angles and confined spaces where a straight wrench won’t fit. However, mechanics do not find their use.

First of all, socket wrenches struggle to deliver the kind of grip and power you really need when working with a fastener. This can be frustrating because it causes you to constantly slip while operating the wrench. This has led people to find other ways if they need to access those tight spaces inside the engine. That alternative usually involves more unpacking. This means removing the surrounding parts to create the access required by a conventional wrench, which takes more time but proves more reliable.

To be fair, moon wrenches are useless. In really tight engine bays, a moon wrench can occasionally speed things up. The key word here, however, is “occasionally.” Some people admit that they rarely reach theirs. If you’re building your tool kit and working on a budget, wrenches are the type of purchase you can skip right now. A good set of torque adapters will work best for you in a wide range of situations, and a few standard wrenches will cover most of what a moon wrench does. Like most tools on this list, the moon wrench isn’t a bad product. It rarely finds its place in the everyday DIY toolkit.

Plasma cutters are top tools for automotive work. They are used to cut thick metal and steel, and reach tight angles that other cutting tools cannot manage. However, unless you are doing a lot of construction work, or plan to do a full body repair on your car, this should not be on your shopping list for several reasons. The first thing that often catches people off guard is the setup. Unlike an angle grinder, which you can pick up and start working with in seconds, a plasma cutter requires a proper power source, air compressor, hoses, and connectors before your first cut. That process takes time, and it’s not always accurate, especially if you’re new to the tool.

Then there are the costs. A decent 45-amp plasma cutter will set you back about $800, and that’s when you include the air compressor and necessary accessories. Leave the 60-amp unit, and you’re looking at $1,000. You can find cheaper options, but mechanics will always warn you that cheapness on a plasma cutter is something that many people end up regretting.

Besides cost, there is the matter of space. A plasma cutter is not a compact tool that you put in the cupboard when you are done. The machine itself is large, and a full setup takes up a certain amount of space in your garage. For the working professional who uses the tool every day, that trade-off makes perfect sense. With a DIYer weekend that may reach two or three times a year, it’s a lot of space to devote to something that sits idle.

Spark plug testers are tools you can use to test each of your spark plugs to see which ones are faulty, so you don’t have to replace the whole set. But the thing is, they only tell you that the spark plug produces the spark and nothing about the entire ignition system. It won’t tell you if the ignition coil is failing or if the fuel system is working properly. You can run all the plugs through the tester, get a clean result from all of them, and still have no real idea why your engine is malfunctioning.

Conversely, a good OBD-II scanner will point you directly to the opaque cylinder, giving you a very useful starting point. From there, you can inspect the spark plug yourself and check for corrosion or unusual wear. This way, you can tell if you have a bad spark plug.

There is also the point of cost. For most everyday vehicles, especially four-cylinder engines, a full set of spark plugs is not expensive. If your car is already approaching the mileage at which you need to change the spark plugs, the smart move is to take the whole place and be done with it. The idea of ​​checking each plug to save the cost of one or two replacements starts to look more economical when you measure the time it takes, and less so if you pay the mechanic by the hour. At that point, the labor costs of inspecting and selectively replacing the plugs will likely exceed what it would have cost to replace them all in the first place.

There’s a good chance you’ve come across an advertisement for a universal socket; are widely sold. A pitch is a single socket that holds any fastener, any size, any shape, replacing the need for your entire socket set. The way they work is that inside the socket, a set of small spring-loaded pins compress and mold themselves to whatever fixture you place on it. In the right conditions, and for small, simple fasteners, it works. But the gap between what it does in the right situations and what it is advertised to do is very wide.

The first problem is balance. A standard socket sits well on the ratchet and rotates well because it is designed for that particular shape. A universal socket, on the other hand, does not always lock into the exact center of the connector. The result is a shaky fit that makes the tool feel wobbly and unable to turn. Another thing is its inconsistency. The pins find their way around the fastener, but they don’t lock into place with the same rigidity as a solid, purpose-built socket. When you introduce any real power, the socket can slide around the fuse rather than turning it.

Take the Gator Grip universal socket, for example. It works well on smaller heads, but on larger, tighter bolts that need real torque applied to them, owners complain that they aren’t built to absorb that kind of pressure. To make matters worse, if you try to use too much force, you risk breaking the tool completely. Admittedly, this tool has its use cases. If you’re working on something as simple as a bicycle, a universal socket may be sufficient. But this is one tool you will never find in a pro mechanic’s garage.

Texas Twister is one of those tools that tries to solve a problem you didn’t even know you had. The idea behind it is that, rather than buying a dedicated slide hammer, you simply attach this adapter to the air hammer you already have, and it gives you the power to pull the parts instead of just pushing them. With one adapter and one tool on hand, you suddenly have an air slide hammer. The problem, mechanically, is that it’s not a practical tool.

Out of the box, the kit includes a CV axle popper, a selection of buckets, a hook, and a set of extension bars designed to extend your reach into tight or awkward areas. However, those extensions do more harm than good. The air hammer works by delivering a series of rapid impacts to one area, and it works best when that energy can travel in a clear path. The minute you introduce expansion bars into the setup, that changes. The bars absorb most of the vibrations produced by the hammer, reducing the amount of energy available for work.

Also, the lock nuts that secure the various heads in place have a tendency to loosen during use, and this happens no matter how carefully you tighten them beforehand. Due to a combination of these reasons, this product simply does not produce the traction needed to get the job done. If you find yourself in need of a similar, versatile tool, you may want to consider looking for a nine-way slide hammer.

The automotive tool industry is a multi-billion dollar market, with new products coming out almost every week. These tools are often advertised as essential, leading many DIY mechanics to believe that the more tools they own, the better technicians they will be. We wanted to put together a collection of tools that professionals themselves have actually bought, used in real repair jobs, and formed honest opinions about. So, we went straight to the source. After scouring YouTube and dedicated automotive forums, we’ve found testimonials from working professionals and seasoned DIYers who describe their most unwanted tools, and where they did or didn’t deliver.

We’ve also made a deliberate decision to focus on tools you’re likely to see. There was no point in building a list around obscure, specialized items that might resonate with a few mechanics. Every tool here is something the average DIYer or home mechanic might consider buying. We’ve looked specifically at consumer forums like Reddit where people have even asked for reviews of some of these tools, so here’s a targeted look at everything you need to know about whether these tools are actually worth your money.