I recently purchased a 1986 1/2 ton lb scottsdale w/ 41000 original miles. It need new front pads so I changed them out with no trouble, but now that I have put the new pads on the caliper is not seated tightly. When I push on the brakes it won't move but just driving around when I hit a bump or a little rough spot in the road I get an awful vibration/sound coming from the front. How do I get them to fit snuggly??????