Radiator shutters . . and you're gonna eliminate those heavy batteries by adding air start? (Would be cool for the sound you have to admit).
I'd want an over-ride or backup on the radiator shutter, and it's a great idea. My initial thoughts towards one were to use a vernier-control cab-mounted item.
Being able to eliminate the use of a winter front and control rad-temp (and to an extent, inlet air temp) is an obvious answer. I haven't searched for an example on a light duty pickup but will now (as I'm also interested).
I read somewhere that in re belly work that a "skin" from body sheetmetal lower edge to frame rails accomplishes much (for little, thus my remembrance . . and skill level).
An exhaust brake is also effective in cold start work. And ir-replaceable in towing, IMO (I'm an RV'er and lately again a truck driver doing oil field hotshot in 1T and big trucks). Our loads with a C&C 3500 and 40' gooseneck rarely exceed 15k on the trailer, but that makes the GCWR somewhere around 30k. The exhaust brake is a huge help in smooth deceleration. Truck drivers and RV'ers have the same problem of learning to use every foot of roadway effectively. The DODGE C&C Manual recommends the exhaust brake for any trailer of 10k and above (I'd say 8k).
Some further thoughts:
KENWORTH in their famous White Paper on fuel economy (and CUMMINS) note that further refinements include the number of steering corrections per 10 or 100 miles, and brake applications as parameters to monitor in fleet applications. A note, in other words, that steering play should be eliminated, and the BEST brake controller for the trailer be used (MAXBRAKE at present, IMO) as well as drum adjustments [and electrical continuity]; caliper actions, alignment on both vehicles. etc, be checked.
I like to think of highway economy -- and especially towing economy -- as being able to remain
lane centered with the least or lowest effort despite all external conditions of road, load, traffic or rig. A light touch is all that is needed. If not, then more work is needed on applicable components or systems. Establish the best possible mechanical baseline, then the aero will be clear as to benefits.
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