ABS light issue
 

I've got a 2000 silverado with the 5.3 and 4wd.

After taking it through some light 4wheel driving, the abs light has been coming on.


After ~3 miles the abs light comes on in the dash, and as soon as it comes on the e-brake light flashes at random times and the speedo needle gets shaky. But only when the abs light comes on, otherwise it acts fine.

Bad wheel speed sensor?

My e-brake light on the dash also started flashing "randomly," or so I thought. It was actually flashing a trouble code (DTC). It is "13" I think. The brakes still work. I haven't investigated it yet. I only have ABS in the rear.

The shaky speedo needle is odd. Haven't heard of that one before.

UPDATE:

I got an abs diagnostic ran, I don't have the exact codes at my desk but it returned 5 or so codes ALL having to do with the left front and rear speed sensor.

Seems strange to me that all these things are happening at once, makes me think its a bad wire/ground. I guess at worse I'll replace a sensor and see if it clears some codes.

Any other ideas?

I replaced the rear speed sensor just now, drove it around the the transmission is still super eratic (downshifting when it doesn't need to)

Do I need to get the abs codes cleared for it to take affect?

This issue is making no sense to me.

Either clear it or a several key cycles and it should turn off.