S-10 ABS light

Heres my latest problem that I hope someone out there can point me in the right direction.
I have a 2000 S-10 2.2 auto 2wd. At about 55 mile per hour the ABS light will come on and the speedometer will start moving erraticly,5-7mph. Also the brake light will come on and off with no frequency at all. There is no loss of braking and the fluid level is fine. Any suggestions whats causing it, and could I easily fix this. I do have mechanical skills and I am not affraid to attempt anything. Please reply back here or at my address of [email protected].
Thanks!
Chris

Your electrically controlled speedometer cluster is probably not recieving proper speed signal data from speed sensors. When this occurs, your ABS system goes into default by design because it doesn't know when to engage ABS. This will cause ABS light and Brake lite on dash cluster to come on. Probably related to vehicle speed sensors.