so i have a 91 f150 4x4 with the 5.0 and it seems that my "rear antilock" and my emergency "brake" lights are both on even when the e-brake is off, then this morning they turned off again they just seem to come on and off whenever they feel like it. but they always light up together, never one without the other. does this mean i have a bad rear antilock brake valve? if it does where is it and how much are they to replace? if they are easy to get to i might just replace it myself. thanks for any help ford til i die!

 

It means there's air in the system or the fluid is low.

 

Yea low brake fluid will cause lights to come on. But if it is your rear abs valve (RABS Valve), then it is located under the drivers seat on the frame rail. It will be on the slanted part of the frame on the inside. Three 13mm nuts on the outside of the frame. Not to difficult to replace. Brand new they can be pretty expensive. $175 maybe, But you can always go to a salvage yard and pick one up for maybe $30-$40.

 

The "antilock" light automatically comes on when the "brake" light is on, unless the brake light is on because the parking brake is set.

 

awesome thanks for the help ill get on that. anything we can do to keep these old work horses on the road.