2010 F150. I can start the truck up cold run it for a 15 to 20 miles coming to several stops. After this, after I brake to a stop and then give it gas I can hear a metal sound, almost rotational from the rear of the truck. If I coast down a small slope after braking I can hear it until I give it gas and speed up. Once in awhile I can hear it at around 20 mph, anything faster and road noise cancels it, or its not there. Truck has 220,000 miles on it. Had the rear end replaced at 214,000 with a good used rear end that had a 140,000 miles on it. Any help is greatly appreciated.
The best I can suggest is to jack up the rear and start taking things apart looking for wear marks that should not be there. First wiggle the driveshaft and pinion first to check for bad U joints and loose pinion. Then look at the brakes. But this seems like a failing U joint or driveshaft support bearing if you have a 2 piece shaft.
Thank you, that gives me a place to start. It is a one piece shaft so no support bearing. I wiggled the shaft, LOL a few weeks and it was solid, but of course that was then. I do know that when the replacement rear end came in the dust shields where not straight and smooth, they were kind of banged up.
Scraping sounds makes me think of some problem w/ the rear brakes as most likely culprit. Could take rear wheels off, inspect the brakes, maybe disassemble them. But I think the best approach is to ask shop to put truck on lift, supported at frame (not wheels) somebody inside “driving” puts in gear to get rear wheels rotating, then steps on brakes, somebody underneath listens for where the sound is coming from.
Do you have rear disc brakes, or rear drum brakes?
Maybe the often overlooked park brake shoes?