[bkreigsr]

My '05 Touareg (TowRig) with 83,000 miles is transmitting a lot of road noise into the cabin. Granted it could use new tires, but before I throw $1K after new rubber, I wanted bounce this off the brain trust.
Some facts:
Of the 40,000 miles I have put on it, 85% of the miles have been towing my trailer and track car (4,300 lbs. combined)
I had the dealer replace the driveline (center bearing failure @ 73,000) and drain, flush and fill all the driveline gear.
This is when the excess road noise got worse. I know the upgraded drive line for the Touareg/Cayenne has a heavier duty bearing, maybe transmitting more noise?
Is it possible that they skipped the flexplate alignment on either end?
Also, if I replaced the fluids with a heavier viscosity fluid that the noise would be reduced?
We just got back from Cape Cod and the wife said it was like driving with an outboard motor humming in the rear seat.
Thanks in advance.
Bill K

(after reading through my own question - looks like the mostly suspects are wheel bearings? - are these usually done on all 4 corners at once?)