"2007 Chateau with Chevy V10"
Is it a Chevy Workhorse chassis - would have a V8...
Or a Ford chassis (F350/F450) with a V10...
I'm sure some will mention the Five Star Tuning... an after market product that can adjust performance - a bit pricey...
Custom Dynomometer Chassis Tuning Products and Services - 5 Star Tuning
My experience is with the Ford chassis - can't comment much on the Chevy Workhorse - but I'm sure others will chime in.