I Posted a question concerning this a while back. Someone said that Ford posted a TSB about pulling the driveshaft and greasing (special grease) on the spline to eliminate this thud when taking off from a standstill. The dealers I have talked to said they do not know anything about this. Any assistance is greatly appreciated.

 

Here's how to DIY.

 

Go take a look at post " thud problem solved!!! " it talks all about this.