I need to buy new axles, since one of mine is bent to crap. There is an option for ABS, which I'm pretty sure I have. But I can get either 3 channel ABS, or 4 channel ABS. I have no idea what they mean or which one I need. My car is a 99 Z28 w/ traction control(ASL). I think there is a light that says "ABS INOP" on the dash, so I should have ABS. On the stock axle there is that gear looking thing with the magnetic sensor right next to it which is bolted to the backing plate.

Anyone wanna tell me whether I need 3 or 4 channel ABS, or just explain what they mean?

Thanks a lot!

 

Since you have TC (ASR), you've got 4 channel...controls each wheel/brake individually (LF, RF, LR, RR).

With 3 channel, it's just LF, RF and the rear two as one.

 

If you have traction control, which you do, you have 4 channel. It is nothing more than the number of sensors on the ABS system. In your case, there is a sensor at each wheel. If you don't have TCS, then you just have a single sensor on the center of the rear-end housing on top of the chunk. This makes it 3 channel, or 3 sensors.