I have been wondering for the last few weeks whether or not my '08 TRD Prerunner needed the rear leaf TSB. Today was the first time I really had enough weight in the bed to really test out the suspension and from what I could tell, even though it is only a three leaf set up, I had no bottoming out. I have tried to find out if they beefed up the metal by making it with a more rigid alloy but haven't been able to find any information. The part numbers are slightly different (the '08 ends with a F) so this could be the case. It really doesn't make much sense to me to just leave that 'flaw' in the newer model year.
Any body have any thoughts on this?