JKOwners Forum banner

Installing JL axles onto a JK

39323 Views 49 Replies 19 Participants Last post by  thedirtman
Long story short, I ended up installing 2018 Sahara JL axles on my 2016 Sport JKU.

JL axles are a bit wider, given I've got adjustable control arms, track bars, the geometry is pretty much spot on. However I ran into a few issues:

- Rear JL axle shock mounting brackets needed to be angle-adjusted, since JL shocks are mounted onto the inside of the frame. Easy fix - cut ant weld the brackets back on.
- Rear diff drive shaft flange is slightly different, but Adams Driveshafts made me a set of driveshafts that work perfectly, I needed new ones anyway.

- Now is a more complex issue and I hope people can help me to figure it out. It seems that JL wheel speed sensors work differently, because I get almost double speed shown on the dashboard, i.e. 40mph instead of 20mph. I did count the number of tone ring teeth which seems to be 52, same as JK. I did program correct axle gear ratio, tire size, etc.

Wrong speed measurement is annoying, but what's more annoying is the fact that my traction control is playing up, it tends to kick in hard when I am making turns at slow speeds. The light flashes and brakes are kicking in. No error codes are shown that the wheel speed sensors are bad or malfunctioning.

So I am puzzled here. I do have a way to debug the hell out of my jeep, so any tips and help is much appreciated.
  • Like
Reactions: 1
1 - 1 of 50 Posts
So I have some good news.

I swapped the front wheel speed sensor, used the JK one, which fits right in perfectly. The JL one has a green rubber ring.

Then I went on to check whether the wheel with JK sensor in, is reporting half the speed compared to the other wheels. BINGO - it does.

I had a spare JK rear wheel sensor, so tried to swap that, but apparently JL and JK rear wheel sensors are quite different, JK one is a lot bigger. But I figured it wouldn't be so hard to make the hole that the sensor is pushed through a bit bigger, since the rear wheel sensors are exposed anyway, unlike the front ones.

Here are some pictures how the look and where they mount into the axle.

I just ordered 4 new JK sensors and I will install them. I think this is going to be it. It makes total sense now why my traction control and transmission was going mental. Will keep you posted.

Hey, I am currently doing this swap and I ran into the rear speed sensor problem. I drilled a bigger hole for the sensors but it is still throwing my jeep into limp mode because of the rear speed sensors. Do you by any chance have any pictures of how your wheel speed sensor is sitting by the tone ring? Or a picture of how big of a hole you drilled? Maybe I'm doing something wrong but from what I read on this forum I did everything correctly.
1 - 1 of 50 Posts