Rock,
I just don't trust the filter minders. But just opening up the airbox did show that there's a airflow restriction because of the fender.

MikeyB

 

I am running a homemade torque tube and a drop in AFE PG7 and when pulling our trailer I can pull the filter minder down about 1/3. I would like to drill a few holes in the stock airbox but I do not want to increase the noise inside the cab. Will drilling a few holes in the filter box increase the noise level much or will it be about the same as it is now? Thanks

 

After I drilled the holes, normal driving noise is not increased but my exhaust brake noise is now louder and sounds great! I am not sure if my egts are lower yet, still hitting just over 600 post turbo empty on hills in 6th. I am pulling the 5er this weekend so I will have a better idea on lower egts after the tow. I am also planning on experimenting with 5th versus 6th on hills also.

 

After action report. I pulled the 5er to the lake and back this weekend. Yes, the egt seems to be lower. I never went over 850 degrees post turbo. I did try and use 5th up some hills, the rpm was about 2400 when I did it and the egt went up significantly. If I left it in 6th I would loose a couple mph but the egts stayed lower then downshifing. I did have a side/head wind going out so the truck had to work pretty hard. Coming home there was only a slight breaze and the truck pulled all the hills without loosing speed in 6th, never went over 800 on the egt cruising at 65 or so. Thanks for convincing me to drill the holes guys, your advice is well taken. Now, staight pipe or better flowing muffler?

 

Hunter11,
I did mine and did notice a slight increase in noise. I did it before removing the silencer ring and intake baffle.

MikeyB