Hey everybody,

I have a 99 F-150 SuperCab 4x4. I am having issues with my ABS system. A few months ago the ABS would engage violently, the brake pedal would be stiff, and the ABS light would come on. After it came on the brakes were fine. This would happen on the first drive in the morning or after work. At first I replaced my right front wheel bearing with the speed sensor, it didn't work. So I did my research and I replaced the rear differential speed sensor and every thing was good to go for a month or so. Well... it's coming back. This time a bit differently. It is now happening randomly.

What is happening is I will get a soft ABS engagement at slow speeds. Like just leaving in the morning at the first stop sign it will engage the ABS very faintly, once I get going the ABS light comes on. It's not flashing and when I shut the truck off at work it clears the light. So I pulled the rear speed sensor, it had a little metal flake but nothing serious. The next morning it did it and again just leaving work. Then this morning no issues. But I was almost home after stop and go traffic the whole way for about 20 mins, it happened again. A soft ABS engagement coming to a stop then pulling away the ABS light came on.

Could it be the front left speed sensor? The rear speed sensor again? Is there a way to pull the code with out the special $400 code reader? I have a really good scan tool but I can't get a code for the ABS. Plus, once I shut the truck off the light clears. I'm stumped any ideas would be great!