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.