Socket Set for Car Repairs and the Sizes You Actually Use

You are standing in a tool aisle looking at a 216 piece kit for 120 dollars next to a 40 piece set for 45, and you have no idea which sockets you will actually reach for. Buy wrong and you end up with a heavy case full of sizes you never use and still no 10 mm deep socket when the battery clamp needs it. This guide covers how to choose a socket set for car repairs based on the jobs a home mechanic really does.

I have worked on cars for over twenty years, and the sockets that are worn smooth in my drawer are a short list. Start there, and spend the rest of your budget on quality rather than piece count.

The sizes a socket set for car repairs must cover

Almost every car built in the last 30 years uses metric fasteners, including American brands. Unless you work on classic British or older American vehicles, you can ignore imperial sizes for now.

These are the sizes I use on nearly every job, from oil changes to brake work:

Check your own wheel nuts before you buy. If they are 21 mm or 22 mm, many smaller sets will not include them, and you will need a separate impact rated socket anyway.

Drive size and why 3/8 inch does the most work

The drive size is the square hole that fits on the ratchet. Even metric sets use imperial drive sizes, which confuses everyone the first time.

• 1/4 inch drive covers roughly 4 mm to 14 mm. Ideal for small fasteners in tight spaces, like interior trim and fuel injector clips.
• 3/8 inch drive covers roughly 8 mm to 22 mm. This is the workhorse for 80 percent of engine bay and brake jobs.
• 1/2 inch drive covers roughly 10 mm to 32 mm. You need it for wheel nuts, suspension bolts, axle nuts and crank pulley bolts.

If you can only afford one drive, choose 3/8 inch and buy a single 1/2 inch breaker bar with a few large sockets for wheel nuts. That combination handles almost everything a beginner should attempt.

Six point, twelve point and deep sockets

A six point socket grips the flat sides of a bolt head. A twelve point socket grips the corners. Six point sockets are much less likely to round off a stubborn, rusty bolt, which is the single most frustrating thing that can happen in a driveway repair.

Twelve point sockets are only worth having for specific fasteners designed for them, such as some exhaust and engine bolts on older cars. For a first set, insist on six point.

Deep sockets matter more than most kits suggest. They reach nuts on long studs, such as shock absorber tops, exhaust flanges and some battery clamps. You want deep versions at least for 10, 12, 13, 14 and 17 mm. Cheap kits often include deep sockets only for the small sizes nobody needs.

Extensions and a universal joint

A good set includes a 75 mm, 150 mm and 250 mm extension in 3/8 inch drive. A wobble extension or a universal joint gets you to bolts at an angle, like the top starter motor bolt. If your kit lacks these, add them for about 20 dollars.

Why a bigger kit is not a better kit

The usual advice is to buy the biggest set you can afford because you will "grow into it." I think that is backwards. Big kits pad their piece count with bits, hex keys, tiny 4 mm sockets and duplicate adapters. A 216 piece box might contain only 40 sockets you will use, and the case is so tightly packed that every tool has one place it fits and you lose time hunting for it.

A mid sized set of about 90 to 130 pieces from a known brand usually has better ratchets, cleaner chrome and a lifetime warranty. Spend the difference on what kits leave out. In my experience that is a proper breaker bar, a torque wrench and a set of impact sockets. Our list of garage tools worth buying first puts those in order.

Ratchet quality is the other hidden factor. Look for 72 teeth or more, which means a 5 degree swing arc. In a cramped engine bay where you can move the handle only a few centimetres, a 36 tooth ratchet simply will not click over.

What to spend and which tier to buy

Prices change, but the tiers stay roughly the same:

• Budget, 40 to 70 dollars. Fine for occasional jobs. Ratchets wear quickly, sockets may crack under a breaker bar.
• Mid range, 90 to 200 dollars. Brands like Tekton, GearWrench and Icon. Six point sockets, 72 to 90 tooth ratchets, usually a lifetime warranty. The best value for a home mechanic.
• Professional, 400 dollars and up. Snap-on, Wera and similar. Beautiful tools, but you are paying for a level of daily use most driveway mechanics never reach.

One firm rule: never use chrome hand sockets on an impact gun. Chrome sockets are hard and brittle and can shatter. If you own a cordless impact wrench, read our impact wrench buying guide and pair it with black impact rated sockets.

Looking after the set so it lasts

Wipe off oil and brake fluid after each job and put every socket back in its place. Store the case off a damp concrete floor. Once a year, put a few drops of light oil into each ratchet head and work it in both directions. When a bolt needs a specific torque, finish it with a calibrated tool, not the ratchet. Our guide on using a torque wrench correctly explains why.

Frequently asked questions

What size socket set do I need for basic car maintenance?

A metric 3/8 inch drive set from 8 mm to 19 mm, with six point shallow and deep sockets, covers most maintenance. Add a 1/2 inch breaker bar and the correct socket for your wheel nuts. That handles oil changes, brakes, batteries and belts.

Are cheap socket sets good enough for car repairs?

For occasional light jobs, yes. The weak points are the ratchets, which wear or slip, and thin sockets that can crack on stuck bolts. If you plan to do brakes or suspension, a mid range set with a lifetime warranty saves money in the long run.

Do I need both metric and imperial sockets?

Not for most modern cars, which use metric fasteners throughout. Buy imperial sockets only if you work on classic cars, older American trucks or some aftermarket parts. You can add a small imperial set later if a job demands it.