Wow, just woke up and already tons of great information! I'll have to tackle these one at a time...
@rmay635703:
Unfortunately the only similarity between the trucks and vans is the powertrain... You didn't mention if yours was 2WD or 4WD, and that obviously has an impact on weight differences. We both seem to get the same mileage, but aerodynamics is my focus at the moment, and our vehicles are too different in that regard
It's been running Mobil-1 Truck/SUV oil for a while, but a lot of people are suggesting I switch to Valvoline, which I plan on soon. I've done some little things just to make the engine breathe better (Dynomax exhaust, modified the intake manifold, 180° t-stat)
As far as overall powertrain health... the engine was replaced with a warranted 80,000 mile engine a couple months ago, transmission was rebuilt 2 years ago, and the axle was serviced and swapped to limited-slip months ago... so everything should be good.
The old engine had a heater but it didn't help much. Maybe I need a bigger one?
@Andyman:
Tires are simply too expensive for me to keep two sets, plus getting ahold of another set of four chrome factory rims is a challenge. There's also few options for LRR truck tires... that flying brick weighs 5,000 pounds, so it needs strong tires. Thermostat is good, heat is enough to make me sweat in below-zero outdoor temps... It's OBD-II and my check engine light is off. If I use a code reader I only occasionally get a "Transmission Temperature Out Of Range" (too cold, not enough to trigger a CEL)
@rmay635703 (Again. Didn't see the last post):
Right now I have my rear tires at 45psi, front at 42. They're rated for 55 max cold. Also, you work near Oshkosh? I'm just south of Fond du Lac, and I drove up to Oshkosh every day for work! I've noticed the engine "feels" more efficient giving it some gas, not just babying it. I installed a tach to keep track of engine speed and I usually have it at 2000rpm (±100) when accelerating until it hits overdrive. At 2,000 those engines put out 105hp and 275ft-lbf of torque, so they definitely have some power available!
I'll at least try smoothing out airflow leading up to the control arms, and I will definently have to try the wavering. A good portion of my drive is up or down a large hill, so neutral coasting sounds like it could be helpful. I wonder if the wavering at a stop improvements has to do with the low idle speed... mine idles at 500rpm, but wavering the gas would bump it up to 1,000 before trying to move the car. I'd imagine if you don't waver the pedal, trying to accelerate from 500rpm is just wasting gas.
Hard to discourage me when I've got nothing to lose trying