When comparing the diesels to the gassers, the diesels have the same set-up for cooling, condenser, tranny cooler, radaitor, but the diesels have an additional unit to pass air through, the precooler (can't think of the proper name right now). The other thing to think about is the static pressure of the fan. The electric fans are designed for the standard set-up, no a diesel set-up. a 5500 cfm rating could be rated at a static pressure designed around just a thin radaitor, when you add condensors, the static pressure rises, add a tranny cooler, the static pressure rises, add a pre-cooler for the turbo the static pressure rises even more. The higher the static pressure, the less air that moves if the static pressure rating of the fan is small. Air flow ratings are kinda like HP ratings, think of the cfm rating as HP, and the static pressure rating as RPM. When rating them, they take the optimal results they get, that is why HP is always at different RPM's.

So what does this mean? The fans may not pull enough air when going through the cooling set-up of a turbo diesel.

 

Thanks for all the advice. MC, I believe you mean the intercooler. I had thought about how thick all of the heat exchangers are on the front of the engine. After talking with some folks and all the input you all have given me, I think I'll just replace the stock fan clutch and add an auxillary electric fan behind the a/c condenser. This option should still only cost about $150 with parts from O'Reilly that I've looked at. Once again, thanks for your attention and advice.

 

intercooler, yeah. I remembered that yesterday afternoon when I was in the speed shop picking up things for my Chevy. I would probably use a pusher fan in front of the radaitor pack and mount a switch in the cab to control it. Good luck, let me know how it works out, I am thinking of a pusher myself, mine has been getting a little hot latley, but then we had the hottest august in our recorded history.

 

another option is the (expensive) Hayden controllable clutch:

http://www.haydenauto.com/index.htm

fans on commercial diesel vehicles are almost never electric
but you can get the slight fuel economy improvement with a Hayden clutch

take any cfm rating you see on an aftermarket elec fan with a HUGE grain of salt, because they are falsely rating them in free air when they should be rated attached to a radiator that is offering resistance.

the biggest elec fan seems to be the Lincoln factory unit:

http://www.geocities.com/smithmonte/...rkVIII_Fan.htm

 

I bought the 12" electric Hayden and a Hayden thermal clutch yesterday, and a relay to switch the fan on when the a/c is turned on, all for $135.00 at O'Reilly. I should be installing this stuff tonight, so I'll post in a couple days and let y'all know how it went. I'm hoping that the electric fan behind the a/c condenser will also help the intercooler cool more and give a slight gain in power. It probably won't be enough to notice, but it might do a little bit. If all of this works well, I may decide to put another electric fan behind the transmission cooler with a thermostat to keep it cool under heavy loads. I can do that for about $90 or less depending on the thermostat I get.

 

Well, the install went pretty well. The hardest part was getting the fan shoud loosened up to get the fan out and then getting it back in place. I had to mount the fan as a pusher in front of the a/c condenser. It's tight, but the hood does close. The air gets cool faster than it used to, but I still have a problem somewhere else in the system. The compressor cycles on for about 10 secs, then off for a couple seconds, then back on while idling. I can't tell if it does it at road speed since I can't hear it. I'm going to check the pressure to see if it's too high or too low, then decide what to do from there.

 

that sounds like normal compressor operation to me... my wifes dak did it, and both my rams do it that way... so you have the aux fan infront of the condenser and the stock fan still in place?

 

Yes, the stock fan is still there and the electric fan is in front of the condenser, right behind the hood. So the compressor is supposed to operate this way? I'll have to listen to my brother's truck and see if his does it too. I thought it should stay on longer than a few seconds and then off longer than a second. It does seem to be cooling pretty good, even is city driving. The guy at tried to sell me a $35 installation kit with a thermostat to kick the fan on, but the relay was only $3 and works just fine. If any of y'all are interested in doing a project like this, I think it was the blue wire on the compressor that switched the relay on. My friend did the electrical hookups, so I can't tell you everything about it. After seeing how much air the electric fans actually move, I'm glad I only used it as an auxillary and not primary cooling. Thanks for all the help, guys!

 

if possible could you give me the part numbers for what you did.. i have been thinking about doing this too for aux air .. if you have pictures that could help too..thanks

 

x2.

I would love to know parts used and see some pics. Does anyone know if the space between the grill and the condensor is the same for second gens and third gens?