Under the driverside CAb of the truck, there is a point where the Emergency brake has an adjuster. Basically three cables comming to one point with a metal cage. In the cage you should see a threaded rod on one cable with a nut on it. This is the adjustment. tighten it up. My Haynes manual says three clicks of the parking brake pedal is the point where the brakes should start to catch. This is assuming the rear brakes were done correctly. Make sure they are adjusted correctly and the Ebrake cables are attatched, and not broken! if one cable is broken you will not be able to adjust the cable at all. Hope that helps.
