Hy Casey_58, a few questions, is your truck a single axle or tandem, does it have a GVW tag on it somewhere, what engine is in it is there a tag or part number on the booster? We need to know some more facts before we can suggest what part number brake booster you should order. If you could post a picture of your booster that would help a lot, there were two different booster manufacturers being used at that time