a new water pump won't give you better fuel efficiency...if the bearing is fried then you have bigger problems then fuel effeciency.

I used a brand new GMB water pump but im sorry I don't have the part number for it. and it is DIFFERENT than the 2.3 4D55 water pump. I guess you can adapt the 2.3 water pump to the 2.5 with the 2.3 water pipe, they must be different.