Vibrating/shaking from box (yr 2005)
I have a 2005 F150 and I was wondering if anyone else has problems with their box vibrating/shaking, where you can see the back of the box shake while you drive and that you can feel it. It starts shaking at 55 to 60 miles per hour. I put new shocks, new front struts, new tires and rims and they balanced twice. I still don't know what is wrong with it and if it is just common among F150s.
It sounds like it is either a driveline vibration or the park brake is partially engaged. The 04-08 F-150 have a common issue with the park brake becoming partially engaged, if you search "TSB 08-11-1" it will give you the actual Technical Service Bulletin and steps on how to diagnose and repair the problem. "TSB 07-10-9" has information for a driveline vibration.
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