my little sister just bought herself a decent little 97 4x4 S series blazer with 140,000 miles on it...her front brake pads and rotors were well over due to be changed..so we got some wagner pads and rotors and swapped them on..(during this time i noticed the front ABS relucter ring was caked in very old mud, so i cleaned it some)..at first everything seemed to be ok after the test run...she left and got on the highway and at about 60mph she heard a sound that she described as an airplane under the hood....this happened about 3 miles from my shop...i go to where she is and test drive it for myself....at first all is just fine, good pedal feel, no dragging or anything...then at about 70mph i hear the ABS pump kick on (didnt know what it was at that time), and she was right, it sounded like a friggin airplane..by the time we got it back to the shop the front wheels were smoking hot...literally smoking...i put it on the lift and pulled the wheels...the brand new rotors now have a blue tint...so i figured the old rusty calipers were dragging, so with it on the lift i put it in 4 wheel and throw it in drive to watch the rotors and calipers....it seemed like they were dragging some, so i put new ones on and bled the system...now the ABS kicks in at lower speeds on the lift without even touching the pedal...my next step when i get back to the shop is to take it all apart and clean the sensors better....im on here asking if there is anything else i need to address while im in there...i found the link on here to the bulletin for checking the sensors with a DVM and will be doing that as well...any help is appreciated..

 

Back ttt. Anyone??

 

Sounds like the ABS system is losing pressure. Master Cylinder seal failing?

I was going to suggest the TSB checks though, see what that comes back with.

 

Could be failing WSS's (wheel speed sensors).