Leave the lid off the filter....you'll be pleased with the sound. Yes, you'll be sucking in some "warmer" engine air when you're not driving, but the sound is pleasant to the ears...:sweet
I experienced an improvement in the fuel economy on my 2006 6.0L after approx. 15,000 miles where it improved from 15.5 mpg to 18.5 mpg very consistent on the highway. I kept the truck through 50,000 miles and didn't see an improvement any further.
I'm hoping the 6.4L will react the same...
Need more info....
Can you determine where it's coming from (ahead, behind, beside, above, below) ? Is it resonating through the entire vehicle ?
Can you always make it come-n-go at 40mph by coming on/off the throttle ?
I typically plug in 35F and below. Short drive to work for me where I won't start getting warm cabin air until I'm 1/2 way there if I don't use it.
Program for 2-3 hours before you need to leave. Much smoother start on the engine and helps oil get to the hard-to-reach area of the engine...
I think the "Trailer Prep Package" which includes the 7-pin wiring, the Tow Command, the Telescoping mirrors, etc...., is what this gentlemen was referencing.
A few fella's have already hit some key points. The other things I like about the 2008 over my past 2006:
1. PTC heater - cold in Michigan and kicks heat immediately. Set in auto, remote start and you'll be happy.
2. Trailer tow mirrors
3. Audiophile system (impresses everyone who has...
Gotta wonder if removing cold air intake (aka: snow collector on Northern trucks), and routing directly to the side vent wouldn't net a helluva lot of intake whistle ? :sweet
Who's gonna try it ?:stir
Ran a powerpoint to the backseat. No longer have to route a cable over my wife to power the kids 12volt power needs (DVD, Computer, etc...). It was warm in Michigan today (58f) a far cry from the (4f) last week - balmy ;)
https://www.fleet.ford.com/TRUCKBBAS/non-html/Q117.pdf
For 2008 there has a change to the wiring colors. Open this PDF file and mid-way through you'll find the colors for the 2008. Good Luck.
My current uses:
1. Air Horns
2. On Board Air Compressor
3. High Idle
4. Remove Start...