[Christ]

Ok, so I basically want some input on what anybody has been using for lubes that has the same/similar parts on their vehicle.

I'm only using non-petroleum fluids, so no dino recommendations, please.

Engine - 4.9L I6 300ci - 5w30 recommended
Transmission - M5R2 (Mazda OD) - ATF recommended
8.8" rear differential - 75W90 w/ Ford brand Friction Modifier
Dana 44 front differential - 75W90 w/ Ford brand Friction Modifier

Of course, I'll be using the truck to tow occasionally.

My question is, since I'm interested in getting the best fuel economy I can with this truck, are there any suggestions other than the mfg's suggestions for fluid, or are these about as good as it gets?

I know for engine oil I can use 0w30, and I'll probably even go as low as 0/5W20, if I can find it. Brand isn't really important as much as it being non-petroleum.

Transmission - Is ATF really the best way to go here? If it is, I can get synthetic ATF pretty cheaply at Wally World.

75W90. There was a TSB at some point detailing the use of SYN 75W140 w/ 4oz friciton modifier, but I don't really see myself going to a heavier weight oil, especially when I've seen trucks run for their entire life without a diff oil change. I suppose I'm asking if I can go lighter than this, even though I'm going to haul/tow with it? Also - is the friction modifier necessary?

Greases... is it going to make much of a difference if I wash the bearings and re-pack them with synthetic grease? I'm sure it's never been done... What syn grease should I be using to keep rolling resistance to a minimum?

I'm not sure what I'm supposed to use the t-case, either... but I assume it's an extra 2qt of ATF.

Anyone?