Flare Nut Wrenches Vs. Crowsfoot Wrenches

It can be difficult deciding between buying flare nut wrenches or crowsfoot wrenches for removing brake and hydraulic lines on your car. Both are great tools, and I highly recommend having both, but if you’re on a budget which is the best bang for your buck? I did a little research and asked a couple of professional mechanics and a group of thousands of mechanics on a Facebook group and here is what I found.

Flare nut wrenches are like a regular open ended wrench, except that they are typically built sturdier and include an extra part so that they can grab the fastener tighter. Crowsfoot wrenches are basically if you cut off the end of a flare nut wrench and made it so you can drive it with an extension and socket wrench. Most mechanics agree, first buy a flare nut wrench set, then buy the crowsfoot wrench set when you can afford it. Both are designed to prevent rounding off of flare nuts on cars and trucks by grabbing the fastener tighter.

Both crowsfoot wrenches and flare nut wrenches are awesome tools. If you can afford high-quality sets in both that is ideal.

Quick Warning: Neither crowsfoot or flare nut wrenches are a tool that you want to buy the cheapest one. I highly recommend only using high-quality flare nut wrenches or crowsfoot. Cheaper wrenches typically have lower clearances, meaning more likelihood of rounding off fasteners. If you round off a fastener that is going to brake lines or a clutch line you are in for some serious trouble. However, if you cannot afford to buy high-quality in both, spend your money on a flare nut wrench set first. Then save up for a crowsfoot set later on.

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Flare Nut Wrenches VS. Flare Nut Crowfoot Wrenches: What’s the Difference?

Flare nut wrenches are simply a regular wrench with one or both ends having a flare nut side which is designed for better grip and safer removal of flare nut fittings, whereas, flare nut crowsfeet are a special tool designed to be used with ratchets and extensions to remove flare nut fittings safely. Check the photo below to see the difference.

Difference Between Crowsfoot Wrenches VS. Flare Nut Crowsfoot Wrenches:

Tools are crazy, there are so many different kinds and names. It is important we understand one difference moving forward that will make it easier for discussion.

There are basically two different types of crowsfoot, or crowsfeet wrenches, flare nut crowsfoot or just simply crowsfoot wrenches. Both need an extension and a ratchet in order to loosen fasteners, and both work extremely well in tight clearances. However, the flare nut style of crowsfoot are better at removing brake lines, fuel lines, and hydraulic lines without rounding off the fasteners. You can see the difference in the photo below, the flare nut crowsfoot wrenches have that extra bit that helps grab one more edge of a fastener. Whereas, the regular crowsfoot wrenches look like your typical open ended wrench.

Why are both called “Flare Nut Wrenches”?

flare-nut-crowsfoot-torque-wrench — A big reason flare nut crowsfoot wrenches exist is so you can use a torque wrench on them. Flare nut wrenches must be torqued by feel. Crowsfoot wrenches allow the use of a torque wrench, and you fill them used by many aircraft mechanics (everything gets torqued to spec on an aircraft).

When we talk about a tool being “flare nut” this means that it has slightly more area holding onto the fastener. They are designed so that they will round off fewer nuts and bolts, and yet unlike a fully enclosed box head wrench, it allows you to fit over a brake line or clutch line. That is also why you cannot use a regular socket on brake flare nut lines or clutch hydraulic lines, as you need to slip the tool over the hard line to get it over the fastener. They typically are a little heavier duty and thicker steel to discourage flexing when loosening fasteners as well. They are a just a more sturdy wrench with a bit of extra grab on the edges.

For a video on the difference between a flare nut wrench and a regular combination wrench watch here:

Flare Nut Wrenches VS Flare Nut Crowsfoot: What’s the Better Buy?

flare-nut-wrenches-vs-crowsfoot — Pattern wrenches = flare nut wrenches

You may be asking yourself which is the better tool to buy first. Well, someone posted a poll on a facebook group full of tool people and mechanics. Pretty much everyone agreed, ideally you have both. There are times when a flare nut wrench won’t fit, and also times when a Crowsfoot flare nut wrench won’t fit. However, if you’re just going to be buying one set then stick with the flare nut wrenches to start.

You will use them more often than the crowsfoot, and they will make bleeding brakes and clutch lines a breeze. Plus, if you use an adjustable wrench or another wrench that is cheap/not made for removing flare nut lines then you will at some point round one off. The second you round off a flare nut you need to replace the entire line. Do it on a customers car and you can be certain you will be losing money on the repair.

Best Bang for Your Buck Flare Nut Wrench Set:

I highly recommend starting out with just sticking to metric flare nut wrenches that come in a set. I typically find myself only using my metric sizes (10mm,11mm,12mm,14mm,17mm,19mm), but I mostly own and work on foreign cars. If you plan on working on GM and domestic cars you should have an SAE set (common sizes 3/8, 7/16, 1/2, 5/8) as well. The most common sizes I end up using are my 10mm and 12mm flare nut wrenches for bleeders on brake calipers and clutch slave cylinders.

Please though, do not buy cheap flare nut wrenches. There is a HUGE difference in quality between cheap flare nut wrenches and a high-quality brand. That difference may be what allows you to get a brake line fitting loose, or cause you to round off the fastener leading to a huge safety hazard down the road.

I asked some professional mechanics for some recommendations and here is what they recommended. I found these sets for an awesome price on Amazon.

Best Flare Nut Wrench Sets for Your Buck (From Highest Quality Down):

I personally have found SK tools to be the absolute best bang for your buck for a lot of different tools. They are professional grade tools, so if you don’t want to top of the line the Gearwrench and Dewalt set also are great. All of these sets are PERFECT for the beginner or DIYer mechanic, don’t get stuck wishing you had these for brake and clutch work.

Best Flare Nut Crowsfoot Wrenches:

The best flare nut crowsfoot wrenches will be high quality and will come in a set that includes a nice case. These are an easy tool to loose in your toolbox. The biggest drawback to crowsfoot wrenches vs flare nut wrenches is that you need to use an extension or at least at ratchet with them. Sometimes, this is the only way to reach a fastener, other times you won’t be able to get the crowsfoot to work and a flare nut wrench works better. That is why tool companies have created both, and why both are awesome tools to have. However, most bleeders are relatively easy to get to and the flare nut wrenches offer the fastest solution to the task.

My favorite metric flare nut crowsfoot wrench set is this one on Amazon for an amazing price. At less than $50, it has super good reviews and comes with all the sizes you will need over time. You can also use crowsfoot wrenches to break any fasteners loose that are in weird hard-to-reach areas.

The best SAE flare nut crowsfoot wrench set I found was this one on Amazon. It also is an amazing deal, and if you work on domestic cars you will find you need SAE sizes. I would just personally always choose metric sets first, but that is all a personal preference on what I tend to work on.

Conclusions:

There are some tools it is okay to buy the cheapest one you can get. It usually won’t come back and bite you in the butt, you just may break a lot of tools overtime. That being said, the last tool you want to cheap out on is anything designed to remove flare nut or hydraulic lines. The first time you round off a fastener, you are in for a much more expensive and dangerous situation than if you had just used the right tool the first time.

Professional mechanics agree, you may not use your flare nut wrenches all the time, but they are an invaluable tool in your box. If you don’t have a set and are going to bleeding brakes or clutch lines, just be sure to use a 6 point socket to first brake the bleeder lose then use a combination wrench to loosen and tighten for bleeding. Never brake any flare nut lines lose with an open-ended combination wrench first, you will be bound to round one off!