So I'm tossing around the idea of throwing a 4L80 in the Malibu to try and squeeze a bit more MPGs out of my 454 (I know, I know, I'm the only guy trying to get efficiency out of a big block,) and am wondering if there is anything I'm overlooking here. With my 2.28's, I cruise at about 2100 rpm at 70mph. With the 4L80, that should come down to about 1600rpm, before the converter locks up. Not sure how much more it will drop with the converter locked. Should I be worried about anything here? Only thing that crosses my mind would be proper oiling on my hour long commute to work. Would a high volume oil pump be the answer for that? Do I really need to worry about sucking the stock pan dry with a high volume pump? Any other issues with cruising at such a low RPM? Anyone know how many more RPMs I'll drop with the lockup?