How to Measure for a Custom Drive Shaft

This video will walk you through the steps showing how to take measurements for almost any type of drive shaft.

Why do I need to measure?

Let me explain.

Over the years, we have built well over 10,000 drive shafts for the Jeep Wrangler JK alone. We have built countless more for just about any other type of Jeep, Toyota, Ford, Chevy, Land Rover; all of it. We know that there are often consistently standard lengths for some vehicles, but we also know that some vehicles have wild variations in drive shaft lengths. Rather than get into all the details of all the different vehicles, I will address the low hanging fruit, the Jeep Wrangler JK.

Different lifts.

Take a look at all the different lift kits available for a Jeep JK. The amount of options is dizzying. 3” is 3” though, right? It shouldn’t matter whose 3” lift you install, the length will end up being the same, right? Wrong. I believe the biggest factor here is control arms. Control arms are basically the pivot arms that horizontally attach your axle to the frame. Some lifts come with new control arms, some do not. Some come with fixed control arms, some come with adjustable length control arms. So, if one 3” lift uses the stock control arms but another comes with control arms that are 1” longer than stock, that second kit is going to require a longer drive shaft. It gets even more complicated when they come with adjustable control arms, these are variable length and it is up to the installer to decide how long or short to adjust them. Because there are so many different lifts and different lift manufacturers, it is impossible for us to keep track of all these variables.

Anomalies.

Here is an example of something we have encountered before. One of our vendors, they do a lot of installations of lift kits. They were doing a lot of the exact same lift on the exact same type of Jeep. Whenever they would order, they would just order the same length shafts they ordered the time before. This was fine, it got them the correct fit shafts for half a dozen vehicles. Until one day the front shaft didn’t fit, it was 2 inches different than all the other times. On paper it was the exact same build but for whatever reason it wasn’t the same length. No one could figure out why, but why didn’t matter, what mattered is that it didn’t fit. Stories like this are not common, but they do happen. We have all been there, we go to the local parts store and the part we get doesn’t fit our vehicle correctly. It is supposed to fit, but it doesn’t.

Complexity of different builds.

Sometimes it is straight forward, 3”- 4” lift on a JK. But sometimes people will do motor swaps, axle swaps, or other things that affect the length of the shafts. This can get real complicated and difficult to keep straight.

What does it mean for a drive shaft to fit?

Just because you can get a drive shaft installed, does not mean it fits. Drive shafts do compress and extend, but a common misconception is that they compress and extend to allow them to be a bit of a one size fits all. This is not the case. The reason they do is basically the same reason your shocks compress and extend. Because as you go down the road and your axle moves up and down they need to get longer and shorter. There is some leeway for fitment but not a lot. For most shafts, anything more than 1” off from fitting correctly could spell disaster.

One reason we request measurements when others don’t is because we care.

We want to make sure that whatever you buy from us is going to be the right thing and is going to work well for you. We could send out more “universal fit” shafts and just figure that it is your problem if it doesn’t fit. But that’s not who we are.

Measuring is easy.

It doesn’t matter if the drive shaft is installed or removed. You simply measure the distance from your transfer case yoke (or flange) to your axle yoke (or flange). It doesn’t have to be perfectly accurate; the nearest quarter inch is fine. It takes less than a minute and can be done in your driveway.

It doesn’t affect the price or the delivery time. We don’t charge more or take longer to build custom shafts. You might as well get a perfect tailored fit.

All that being said…if you can’t measure, or just plain don’t want to there are standard lengths that we can go off. If you are getting shafts for a JK we won’t require measurements, just recommend it. For other vehicles however there are enough different length possibilities that we will require a length measurement. It is quick, it is easy, and it could save you from getting the wrong drive shaft.

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