So, on newer trucks, like my '97 K2500HD 6.5Diesel, which has Hydroboost, and my buddies '02 3500 Duramax, they have power steering coolers. If I look at a late 90's 2500HD with gas engine and no hydroboost, they do not have a power steering cooler. So, for those with hydroboost & power steering, are you running a power steering cooler? I would guess those with Ram assist and hydraulic winches and such, they would definitely require the cooler, but with just the Hydroboost and power steering, is a cooler nessesary? Apparently GM thought so, at least on the newer stuff, but I don't think any of our era trucks had a PS cooler on the hydroboost trucks.