THe only thing I could think of is that the hood and fenders needed to be a few inches taller so when the wipers parked they were below the lip of the hood. Probably what really killed it was that the taller hood and fenders were creating a broader leading edge on the front of the truck, and that must have been worse aerodynamically than just having the wipers park on the glass, in the airstream. By my calcualtions, decreasing the height of the hood and fenders by a couple of inches lowered the surface area of the leading edge of the truck by almost 2 square feet. That body ran from model years 1973 through 1987, and was continued for about 2 years later on the suburbans and the 3500 model trucks. The redesign where the wiper cowl was removed was introduced in 1981. Probably taken off in the gas crisis of the late 70's.
I have also heard that the wipers that bow out that give even pressure across your windshield are more aerodynamic. I can't remember what they are called but they cost about twice as much as the conventional ones.
There's a few different manufacturers making similar wipers. My VW came stock with that type of wiper.
1. It's very efficient, relative to the 4.8 and the V6. It varies by year and model, but usually it's rated the same or better.
2. The most important part about making a more efficient model is that people have to buy and drive it. People want the 5.3.
I, for one, don't want a V8 in my next truck. I've always been interested in range and fuel economy, most particularly when I go off road in northern Maine. Full size off-road vehicles are a joke. The Chevy Z71 pkg sucks fuel so badly that I would never buy it as my hunting vehicle. I'd have to drive out every 3 days to gas up.
As for V6's, it's still a mystery to me why GM still uses the antediluvian 4.3 liter V6 engine as the base truck engine, when its 3.9 V6 with Displacement on Demand and variable cam timing is sitting in the parts bin. This engine, coupled to the new 6 speed automatic and 3.23 axles would give good fuel economy in a decent 4x4. Where is my 25 mpg truck?
I am willing to pay V8 prices for a V6 with economy. I'm even willing to pay diesel prices for a gas V6 with economy. WAKE UP, GM, FORD, DODGE!
Capitalism: The cream rises. Socialism: The scum rises.
My step had a 1500 Chevy 350 diesel back around 1980. Just after that they had a bunch of small 4 cyl diesel options in the mini trucks. I almost bought a 1980-something Chevy Luv 4x4 diesel a couple years ago. I kept thinking how hard it would be to get parts for the engine.
I'd like to see the small and mid size trucks get small 4 cyl diesels. And see the full size 1/2 tons get small V-6 or small V-8 diesels in the 200-250hp and 350-400lb/ft range. Even a large displacement (4.0L or higher) inline or V-6 diesel in a half ton would do it for me.