In the past month or so, I have noticed my brake lights staying illuminated after shutting-down and exiting the truck.

Typically, if I go back inside and pump the brake pedal a few times, they go out.

This is a Spartan Chassis with Air Brakes.

Is there some-sort of "plunger switch" right-at the pedal or what actually actuates the brake-lights that would have the appearence of "sticking" and not "releasing" when necessary???

Or ...is there another reason that my brake-lights would be staying-on??? Seems-as-if it is directly something that is connected to the brake pedal.

Any help would be great!

Go outside and step lightly on the brakes and then look at your brake lights.

Pull up the brake pedal. The pedal may be sticking inside of it's pivot mount. I have also seen carpet or a floor mat go under the pedal and not allowing the pedal to fully release.

Another thing is the plunger that is built into the brake pedal housing. These will stick and need to be removed to lubricate.

If this is what's doing it then you have been riding around with your brakes partially applied. Have them readjusted.

The other item of course would be a bad brake light switch. They normally mount these to the brake valve under the pedal below the floorboard.

Thanks for the information Bill N.Y.

After making a few attempts of lubricating the [now known] Treadle Valve and still experiencing the intermittent condition of brake-lights "hanging-on", I finally broke-down and took-it to the shop.

I was able to get the brake-lights to "shut-off", if I would depress and release the brake pedal rather agressively.

Apparently, the actual Treadle Valve was not operating properly, causing the brake-lights to stay-on at times. The problem really had nothing to do with the brake-lights ...the brake-lights "staying-on" was only an indication that there was something wrong with the Treadle Valve; either not being able to expell air properly or maintain a proper pressure.

Treadle Valves are an expensive part.

Anyway... Everything is working GREAT and the brake pedal is so "tight" it nearly puts-you thru the windshield. It's good to know my brake system is working fine and the brakes can stop a 13 ton vehicle on-a-dime.

Thanks for the help!