I already drive it quite conservativly, and have done the timing / tune up. Need a new air filter, just haven't ordered one yet. The sythetic trans and rear end lube sounds like a good idea, I forgot about that. didn't think of the elctric fan either.

Right now, it's pretty much bone stock. I don't plan to really do any mods to it, since I'm not really a performance guy.

On lowering the rpms, what's the sweet spot with the engines? I'm a diesel guy, so I feel like I want the rpms down to about 1500 at cruise, but I think that may be too low and would be lugging it. A couple of things I'm considering would be a rear exle swap to something with a higher ratio, (think I've got a 3.91, try to find a 3.54 or 3.31) which would give me 10-15%, or to try mounting a j-type od box behing the aw71. (harder, but I think still workable) This would put another 30% or so reduction in, but would it be too much?

On the rear axle swap - will a 740/760 axle (solid, not the irs) fit under a 240? How about a later 240 axle?

One of my other pet projects is to try adding an abs system off a later 240 onto this thing, so I need to change the rear end for that anyway.
~John