Took my daughter to the park tonight and when we were leaving, the way i parked required me to back up about 100ft. at about 25ft i hear a nasty crunchy sound come from under the truck, didnt think anything but maybe a can i ran over, but shortley after i hear it again. Slowed to a stop and then continued to reverse and nothing at a light throttle but when i push it faster the crunch comes back. Not exactly sure where the sound is coming from. you guys got any ideas. Ill probably have my wife drive in reverse tomoorow while im outside so i can see if i can pinpoint where its coming from. Only happens in reverse.