Hello Thank for reading. I have a 2013 Ford f150 2 wheel dr V-6 all was well until I had the rear diff seal changed.They said it would require a change of oil to replace seal.Now that is done I have a noise and light shake upon acceleration.It does not happen once moving and only at take off. it really shows up when I back out of the driveway in morning and place in drive it always seems to do it then.My question is what could the dealer have done in exchange the front seal on the diff where the drive shaft enters the diff.Is there a lash type adjustment or similar. Worked on many mechanical items but never diff work. I have owned this since new and it only has 22k miles and it surely showed up after the seal change. Any ideas? I really don't want to return to dealer but I don't know what to tell another shop of what to look at in case they can't hear the noise. Thanks for the help

 

I would be worried that they over torqued the pinion nut. If they over torqued the pinion nut the pinion bearings will have too much preload. I'd take it back to the dealer that did the work.