What are some things I can do to a Yukon to add police package?
GM/ACDELCO Parts can I use
Isn't there a bay for extra battery is that something that is use as well?
I recall on my escalade I added Police ACDELCO Rotors and break pads
What about intake?
There's no benefit to a performance intake until you have a big cubic inch, high revving motor.
The PPV is obviously low optioned and optimized for the job. Suspension wise, it is near the same as the XFE models from 2009-2010. They do have different spec rotors and pads for heat dissipation. The shocks on the XFE will be more for comfort than cornering. PPVs also run a shorter, high performance tire made for high speeds.
GMT900 SUVs have their main battery up near the cowl on the passenger side. There is space for an additional battery at the opposite corner, behind the driver's headlight. Look up TP2 option for one way to tire it up.
Cooling wise, I believe that the PPVs have the larger radiator, 700 watt cooling fans, external transmission cooler (KNP) and radiator mounted engine oil cooler (KC4) like the HD Tow Package called K5L.