Changed the brake booster. The brake pedal now doesn’t return . It doesn’t stay on the floor. Staying in the middle. The truck stops good. But the pedal has the be lifted to hit the brake light off. Could it be air in the lines? Or a vacuum leak? The brake booster doesn’t have a seal on the pedal side. You can hear air every time you press the pedal. Anyone have pictures of what the brake booster looks like going in to the firewall and the pedal?

 

Maybe the pushrod to the master cylinder is too short? did you compare the old booster to the new one?