I put mine on Thursday and did some town driving. I did a 2 hr drive yesterday with the ambient temps in the low 20's, all the shutters closed, about 50 gallons of fuel in my transfer tank, and had 3 passes with about 1500' of elevation change each. I had cleaned my MAP and MAF sensors and was trying to maintain RPM's in the 2200 range for the whole trip. The highest I saw the ECT get was 208 and that was only for a moment. I did go into a regen that took about 30 minutes. FWIW, my overall impression is this might be a very slight improvement to the regen issue, but I seriously don't believe FCA is going to figure this one out to anyone's satisfaction.