[trooper Tdiesel]

bingo, gear venders that's the perfect thing for keeping it above 7 mpg and doing nothing else
3.20 gear is just right...
striped out im thinking it still something like 6,000lbs or so but that's just a gess...being a 1 ton chasse, your not going to get super light.

are you using a trailer for the cargo, or is it all in the RV

the 318 is just fine in my mind, it was a common gas saver 3/4, 1ton engine tell the 90s

in a way having the 360 is a good thing, even though i personly dont like them, the trans housing is the same as a 318.
where if it was a 440 you would need a trans swap or housing change.
so should you want to do that it would not be as hard as if it was a 440

i have no science to prove it. but i think with big aro mods, you can have the drag you had stock at 45mph at 60mph with a much better aro shape.


are delivery truck was a 460 and C6 i know all about a screamer engine and ""galleons per mile"" in the city WOW.
we swapped it out for a 300/6 and a early ZF 5speed truck does little freeway driving so we stayed with the 4.10 gear

is it fast, NO
loaded to 14K can it go faster then 70 at WOT on a flat road, NO
did it make the mpg of the auto 100% better YES
do the brakes last twice as long with the manual trans to help slow on hills YES
can it move the same loads it did with the 460 YES just a little slower.

granted we modded the engine for air flow so the engine could breathe much better. the old 4.9L I-6 had some really restricted air flow, and a EGR that was flat silly to even be there since it was just a pipe.
but did not do a cam change or drastically over sized carb


any way, sounds like your off to a real good start