Since I've been here, there has been this never ending debate over belt driven fans and electric fans (or efans). This video just came out from from Enginemasters which irrevocably proves how much horsepower and torque each type uses (efans were inferred as they used the no fan baseline for efans). However, I remember a truck show on the now defunct Speed Network where they did some mods to a Dodge truck where they were checking rear wheel horsepower changes as they were going and switching from a clutch fan to efans only gained just under 1 HP. My own personal experiences with efans were mixed. Although I did find I had HP and MPG gains, cooling was marginal and A/C performance was degraded at idle. Once I put back a thermal clutch fan, no issues but MPG did suffer a bit (no hard numbers, sorry). We have to realize that GM engineers went cheap on us by giving our platform a marginal radiator and compensated with a big clutch driven fan instead of efans that all the other truck platforms got. I have seen that there is a Dodge car based aluminum radiator that fits to allow efan use. But that, the efans and controller starts making the setup expensive. And. because there is no constant A/C power that doesn't cycle with the clutch, controlling the fans with A/C use is problematic as you don't want the fans cycling on/off with the clutch. Maybe adding a delay circuit on the feed from the A/C clutch might work. I can say when I had the efans, all that space was fantastic. Made replacing the radiator and alternator just a trivial thing and just opened up the engine bay. Here's my original thread on my install at the time: My efan setup (Montana/Venture efans) Now after seeing that video, I MIGHT revisit efans. I have a set from an SV6/Uplander which seem to pull more air compared to the older Montana/Venture fans and may actually fit a little better. I can reuse the controller I had in my old EXT but have to replace the sensor as the wire is quite flimsy and broke right at the sensor. So what's your take on efans? Is it worth the trouble and expense? Should be used only on performance builds?