6 Ways to Measure a Sway Bar
Whether you’re replacing your old sway bar bushings, or just trying to determine what size sway bar you want to upgrade to, measuring the diameter of your current sway bar is vitally important. Thankfully, measuring your sway bar can be done easily and in this article we’ll show you 6 methods to do so.
If you’re more of a visual learner or just don’t like to read, hit play on the video below. Otherwise, keep scrolling.
Locating your Sway Bar
Your sway bar is a long bar of metal between the wheels stretching between the driver side and passenger side on your vehicle. Typically there is a front sway bar and a rear sway bar, although there are some vehicles that don’t have a rear sway bar. The sway bar is usually attached to the vehicle at each end of the bar and at two places near the center of the bar. End links are used to attach the ends of the sway bar to usually the control arm (the end link point of attachment can vary from vehicle to vehicle). Sway bar bushings are used to attach the middle of the bar to the frame of the vehicle. There are other parts near the sway bar that are rod shaped, like tie rod ends or the axle, but if you can find the rod shaped thing attached to the end link you’ve found the sway bar.
Finding the Right Spot to Measure
Once you have located the sway bar, find the spot where the sway bar bushing mounts to the frame. The point where you take your measurement is critical. You want to measure just next to the sway bar bushing in order to get the most accurate diameter for your bar. DO NOT measure on the bend of the bar, as the diameter can be skewed giving you a measurement larger or smaller than the actual bar size.
The Actual Measuring Processes
There are six solid methods to measure a sway bar. Most of them can be done with tools you already have around the house. Other tools can be bought. One tool can be printed for free!
Method One: the Caliper method
By far the most preferred and accurate method is to use a digital caliper. At DST we’re particular to this one that you can find on Amazon because it’s capable of showing fractions.
Method Two: the Free Print-out Tool method
Printout this free Sway Bar measuring tool that we at DST created. All of the calculations have already been done. Make sure that there is NO SCALING when you print out the tool. Otherwise the measurements will be off. Once you print out the tool, take a pair of scissors and cut out the tool. Wrap the tool around the bar and match the starting line with the size line. The measurement on the right of the line will be your sway bar size. You can printout our free sway bar measuring tool here.
Method Three: the Full Set of Wrenches method
Grab a set of wrenches and see which one fits snugly over the sway bar. If the fit is too loose or doesn’t fit all the way over it’s not the right size. If the wrench fits the sway bar perfectly, then take a look at the size of the wrench – that’s your sway bar diameter!
Method Four: the Crescent Wrench method
Grab a crescent wrench and tighten it over the bar. Then grab a ruler or tape measure and measure the distance between the jaws. That measurement is the diameter of your sway bar.
Method Five: the Tape method
Take a roll of tape, and wrap it all the way around the bar one time. Use a razor blade to cut the tape so that the ends match perfectly and pull the tape off the bar. Use a ruler to measure the tape. DO NOT STOP HERE! This will give you the CIRCUMFERENCE of your bar not the DIAMETER. To get the diameter of your sway bar, take your circumference and divide it by π (that’s pi or 3.14159). The result of this calculation is the diameter of your bar.
Method Six: the Sewing Tape method
Maybe you’re just not the kind of guy who has his own tools. If that’s the case, even your Grandma will have the tools necessary to measure a sway bar diameter. If you can raid her sewing closet and come away with a cloth measuring tape, you’ve got what you need. Wrap the cloth measuring tape around the outside of the sway bar to find the circumference of the bar and then, you guessed it, divide by pi.
Now that you have the Diameter
Now that you have the diameter of your sway bar you can replace the failed bushings with either OE replacements or upgraded polyurethane. Polyurethane sway bar bushings give your sway bar the performance of an even larger bar. You’ll not only get a boost in your handling, but you’ll have the durability of a material that is much better suited to suspension bushings.
If you’re having trouble locating replacement sway bar bushings, you can always check to see if any of these universal sway bar bushings will work for you.