My ABS light comes on pretty much all the time (and nearly ALWAYS after hitting a bump in the road). How do I know whether it's the front or back sensor that needs to be replaced? Also, is this "easy" to do?

 

Get your codes read. It may be something as simple as to much of an air gap or dirt on your sensor.

 

How badly do you want ABS?
Each sensor is $450.
It may not be a bad sensor, it could just be loose. Find each one at the wheels and gently tap them bad down into their holders.

 

Oh, believe me - I don't WANT them. In fact, being that the truck is worth $2K (tops), I'd rather never put another penny into it!!! Are the ABS sensors easy to locate? Honestly, I probably wouldn't even know where to begin to look, or even know what I was looking at if I saw them.

 

http://roverparts.com/Parts/STC1749.cfm

This is what they look like, and the price has come down alot.
There will be one at each front wheel and one on the passenger? rear wheel. (there are ony 3 on a DI)
From the front of the truck they are pretty easy to find, look at the hub and you will see the only thing with a wire coming out of it.
If you do a search for "DI ABS" or the like you can find lots of info on DI ABS systems.

 

Thats why you want to get the codes read, maybe remove and clean then make sure they are installed in to the proper depth.