What would be really interesting would be to keep track of your MPG difference with and without it. You would have to try to run a few tanks with it and then a few tanks without it in the same type of weather and driving conditions to begin to even try and be scientific about it.

 

Make sure you keep the fan upright too (same orientation as it would be mounted in the engine), if you lay it down it can damage the viscous clutch.

 

Yeah, I just kept mine standing up on the floor in between the back of the drivers seat and the back seat. I rarely had passengers in the back of the extended cab and when I did they sat on the passenger side so I didn't have to scoot my seat forward too far while driving.

 

You are correct; but According to the butt o meter HP difference is hardly noticeable.. engaged your gonna feel the drag with out it you wont..

Equate to significant MPG gain? Probably not anything more than a .0x gain or so.. depending on how you drive; if you drive like me putting your foot in to it when the clutch is engaged then you might see a better difference... (Or rather that of winter driving slightly) not having it drag the engine when other wise normally engaged.. you might see half a mile difference or so? Thats about what it felt like but that was minimal at best... (At least for me)

Honestly the key points for me..
-less strain on the engine means a little quicker responce from a stop.
-AC works better WOOT WOOT and more consistant instead of nice cold one moment and luzl luke cool another..
-Maybe some better mpg but minimal but over time would add up...

 

You are absolutely right.. using just the AUX fan the majority say it works fine.. I know most cars and trucks have them for their HD cooling and also it was meant if the clutch fan fails it has to be able to keep the engine from overheating.. and the backup.. as well as for the AC part..

Out side of that .. you just have to experiment most modern cars and trucks running on the roads have electric fans; retro fitting any car or truck is simply getting a fan that will pull enough air and having a good shroud to create the proper vacuum effect to get max efficiency out of the fan as possible.

Thats my next project other then basic upkeep is building me an actual custom shroud for my liberty fan and then putting a controller on it.

 

90s 3.8L taurus fans work really well too. They're dual speed and pull a ton of air through. I've been sitting in traffic on 110°+ and humid days, and still have cold a/c and a water temp no higher than ~195°.