I have a 05 F150 4x4 SCAB 43K miles I have the Ford ESP. Just starting making a popping noise when going over bumps. It seems to get louder as you drive more ( warmed upped ) It also seems to be coming from the rear but not positive.

I took it to Pensacola, FL World Ford and they had it for two days. I even drove with the tech and he heard it... He told me it may be the axle in the back shifting back and forth???

Now they just called and told me nothing is wrong and that is normal...

Help...