Dave, yes, that does apply to your truck, and yes, it is a reflash. A dealer should be able to run the VIN to see if it has been done. I had mine done in October 2004. Mind you, prior to the TSB, my overhead was accurate to within 0. 2 mpg of hand-calculated. I did not have the white smoke issue, I just wanted it done to see if it would help my mileage. Here's what it did for me:
1. Computer-calculated mileage went up by almost 2 mpg. Actual hand-calculated did nothing. In other words, all it did was make my computer inaccurate.
2. Really tightened up the shifting of the 48RE, especially Overdrive. No more whoooommmmppppp..... going into OD. Much cleaner.
I think it was worth it for the improved shifting, but if you're looking for better mileage, forget it. Get it done, it can't hurt.
Scott
P. S. - My mileage is the the crapper at the moment, also. (In the 11s, where I'm normally in the 12s). The combination of the very cold weather and winter blend fuel does it. How much did you lose on your PSD with winter fuel. I lost almost 2 mpg on mine (the PSD).