@Blu3Z3rg, I think the belly panels are definitely worth the effort. The largest pain in the backside is figuring out how to get them mounted securely and so they fit together and don't flap around. I had one small glitch a month ago where I hit a big dip in the road @0230 and sent the truck airborne. That was okay in itself (except for scaring my sleeping passenger to death), but my bracket rubbed a ring on the driveshaft, because I didn't clearance it enough. My current panel kit is rudimentary, but it does show improvement over the OEM configuration (none). Once I get things smoothed out, and cover the entire belly, I figure I'll see another mpg or maybe two.
The grill block helps, I think, but I've not done some before/after. I am contemplating blocking about 90%, reinstalling the clutch fan for regular airflow through the radiator, and testing to see if FE would improve. I could probably use the e-fan in the winter, but not summer. I'm sure the e-fan has helped, although I'm not convinced it's as significant as I'd hoped. I still use it to avoid the noise of the clutch fan on start up.
Were the cams worth it? Unsure on the mileage right now. Although, I did notice on the drive to OKC this weekend, going 74 mph the whole way, the truck never downshifted from 5th on any of the hills. That was the first time I recall no downshifts. So, I think the average driver would see some FE improvement... Hope I can go testing this week.
@slowmover, I am with you. Several folks I know have pulled the overload springs, and I am really hesitant to do that. I'm still thinking about lowering it 2 inches. I am a little unsure about changing to 45 series from 60 series...'cuz I do drive it like a truck sometimes, to my wife's chagrin.
@NHRABill, I usually see the tranny lock (I think) as I watch the eng rpms drop slightly going down the road, after it shifts. However, I am curious now if it is really locking up fully... I can add a resistor to bridge a pair of wires going to the tranny that will give a lower tranny pressure signal...hence telling the computer to up the tranny pressure. I might have to get a gauge and monitor that.
@FrankLee, I hear you, as I worked on a farm for years with straight-piped John Deere tractors. I figure I'll wrap the exhaust pipe in insulation, cut the end of the pipe at about a 45* angle, and see if it is still loud in the cab. Hmm, a straight pipe should weigh less than a muffler too!
