Hey, I'm running a '96 Ram B2500 with the 5.2L and 46RE.

What are the real-world benefits I'd see from switching to an electric fan? How difficult is it? How would I handle the extra slack in the belt?

Thanks

 

I would not go electric there are too many things that can go wrong on the raod. If you are having an overheating issue I would address that first. I'd also highly recommened a FlowCooler water pump, These pumps come with an anti-cavitation plate and will keep you water temps at exactly the thermostats temp regardless of ambient air tempor load on your engine when towing.

 

I haven't been having a fan-related overheating issue. I had a 'I'm losing an alarming amount of coolant' problem... but that ended up being a freeze plug. Well, five freeze plugs.

Some people say electric fans have a little less power loss because they aren't belt-driving, while many point out the parasitic draw on the alternator that an electric causes. I just don't know how much of an impact an electric would have on the Magnum 5.2

 

I am a member of a Toyota Supra Forum this efan thing has been hashed out for years, one thing they all agree on now is there is no gain on the dyno or other wise form an efan, In fact its shown they cannot cool as much as your stock fan. Remember those most championing them are usually the ones selling them. Think of all the the problems that can arise, for instance lets just say it locks up, you best notice quick before you overheat on the side of the road. Then there's the sensor's that go bad, etc etc.

 

Many of the Dodge Trucks have switched over to an eFan for fuel economy reasons. The mod pays for itself in less time than four oil changes burning up the fuel during that time.

The clutch driven fan puts too much load on the engine and runs all the time. The eFan comes on when it's needed and is quiet enough to hear the engine actually running.

One of the popular types is the Flex-a-lite Black Magic Extreme 180. It's an aftermarket kit. And like Suprageezer mentioned, things could happen.


However, there is an OEM Chrysler Viper eFan used on the Magnum engine V10. It's a literal bolt on for the V10 Dodge Trucks too. The Dodge Trucks and Vans are Magnum engines as well. So, going OEM will greatly reduce any problems one would face doing this modification. Viper E-Fan (P/N P5007266) & DCC FK-35 controller. (dccontrol.com) If you make the change, make sure to use a pigtail connection (P/N 5014007AA) for any service needed to the radiator or other parts.

The FK-35 is automatic, it works using pulse width modulation (PWM control) so no relays are needed that could go bad, it has a temp sensor wire as well. Basically you wire it to the high speed side of the fan and it supplies power to the fan ranging from 0%-100% based on the cooling needs via the sensor place on the radiator fluid inlet side ... This is best using a PWM controller, unlike the relay method "all on 100% or nothing at all."

Connecting the blue wire from the controller runs the E-Fan @ 50% when the A/C is turned on. It's something to get use to since the temp gauge will move up and down frequently unless you opt for the small secondary fan like the 3rd Gen Dodge Trucks have for the AC condenser core.

The Viper eFan uses a Forward Swept blade technology that is found in many of the better CFM flowing fans of todays vehicles vs. the Flex-a-Lite brands. One issue to keep in mind is the 40amp power draw the motor has to cool down our large radiator cores. Make sure the Ram Van/Wagon has the higher map alternator, battery and cables. Usually, the 1998 and newer Ram Vans are set to go with the higher electrical hardware and the towing package became standard equipment after 2000.

Where to get a Viper eFan? http://www.newmoparparts.com If the site is down, call the number.

If you do a google of " viper-efan " you will find a link showing all of the install steps and pictures.

The best overall performance and cost eFan for the vans is the Ford Taurus dual fan setup. If draws a little less amps, works just as good as the Viper and you can run one fan while running the AC. This has been done in the past as well.

If fuel reaches over $4.xx per gallon this summer, I'll have no choice but to go with the Viper eFan. A friend of mine Dave has already done the eFan mod. He has towed a loaded utility trailer and loaded Ram Van from southern CA to mid- Texas during last summer averaging 19MPG easily. His Ram Van has a V8.

 

Here's an old post about the 'no fan' MPG experiment I ran on a 1995 5.9V8 46RH short bed Clubcab Ram pickup:
=====
April 27, 2001
Following up on the air dam on/off MPG tests I did on Monday the 23rd,
today I did a MPG test run at a cruise-controlled 70 mph over the same stretch
of Interstate 40 without my radiator fan.

I filled up at the same gas station, set the air conditioning the same, and
the weather was nearly the same - 70-79 degrees. Today there was a 10-15 mph
wind coming from the west (more on that later).

The truck was about 4 lbs heavier because I was carrying the big 1 7/16 inch
wrench, hammer, and small 1/2 inch flare wrench I used to remove the fan
bolts.

By the Exxon gas pump I used 11.105 gallons of 87 octane.
By my (corrected) truck's odometer I went 218.5 miles.

MPG at 70 mph without the radiator fan was 19.68
Compared to 18.94 MPG on Monday's test with fan,
this represents about a 3.8% gain.

The Oztrip meter results from measuring fuel injector on-time were similar,
showing a consumption of 11.6 gallons over 218.7 miles
for a fan-less mpg of 19.34
On Monday with the fan the Oztrip had showed 18.86 mpg, or a gain of 2.5%

When I first started this test run at about 10 am, the Oztrip meter showed
surprisingly good MPG - about 20 - so I had high hopes for what fan removal
was going to do.

Unfortunately, I found that part of the gain on the southeast bound leg of the
trip was due to the 10-15 mph winds at my back.

When I turned around at Wilmington NC and headed back, the average mpg
steadily dropped as I now drove against a head wind. Looking at the Oztrip
trip computer numbers it seems I averaged 19.96 on the southeast bound drive
with the favorable tailwind, and 18.7 driving northwest with the unfavorable
headwind. This was the 1st time I had bothered to watch for what winds do to
mpg. Looks like they can raise/lower mpg by 1.6 even at a "calm" 10-15 mph
level.

As to the temperature of the coolant without the fan - it stayed very steady
at 180 degrees during the MPG test run even with the air conditioner on.

When I slowed to a stop at the end of the trip while turning back into the gas
station, the temp gauge indicated a momentary rise to about 195.

I actually took the fan off late yesterday afternoon and drove around without
it to experiment. As long as the truck kept moving the temp gauge stayed at
180. I parked the truck and let it idle for about 10 minutes. This raised
the temp gauge to about 210-220. I then put on the heater full blast to see
if this would lower the temperature back to 180. It did not - the temp stayed
the same and neither fell nor raised any more. I then drove the truck again.
Within 1 mile the temp had dropped to 200 and within another mile it was back
at 180 degrees F.

The fan on a 5.9V8 Magnum is kind of funky looking. It has 5 blades, but 2 of
them are bunched together and the other 3 are spaced out normally. There is a
stiffening wire embedded in the blades. It takes less than 15 minutes to take
this fan off, but if the fan had been made in two parts that split - you would
not have to take the big nut off the fan clutch - and the fan could be removed
in 5 minutes.

Instead of buying a 36 mm wrench {1.417 inches}, I cut two strips of metal
from a tin can. These strips turned out to be 0.010 inches thick. I taped
two such home-made 'shims' to the inside faces of my 1 7/16 wrench {1.4375}
which closed the opening up to 1.4375 - 0.020 = 1.4175 This worked fine to
loosen the clutch-to-waterpump nut. Make the shims 'fish hook' shaped and you
can tape them in place from the backside.

I may try to drive without the fan in city driving a bit to see what happens,
but I am carrying it with me just in case I have trouble.

I still have the Evan Cooling 'waterless' NPG coolant in my engine. This
won't boil over until 370 degrees so I have some safety factor that a normal
antifreeze would not have.

=========
: John_Neff writes:

>Hank,
>I found better results when I installed the electric fan on my Dakota. Mag
>whereas you have the 5.9. My fan is of different configuration that yours
too. >Instead of the 7 blade fan you have, or the 5 blade fan shown in the
Dodge >ad's. I have a monstrous fan with 9 equally spaced blades. It must
weigh 15 >lbs including the clutch. My mileage went from 14.8 to 16.4, not
cruise >controlled, My highway mileage change equates to a 9.2% increase
without >the fan. John

John,
It makes sense to me that a Dakota might have a bigger gain from not using the
fan.

If a Ram uses 60-70 horsepower to cruise at 70 mph, a smaller, lighter Dakota
might use only 45-55 hp. Since the fan wastes about the same same in either
case, the Dakota mpg would go up more.

It is interesting to hear of your bigger 9 blade/heavy fan. Would this be a
'towing package' option that we have not noticed before ?

How much horsepower does the stock fan waste ?
Here's a ballpark guess -

The gaspump said I saved .425 gallons.
The Oztrip meter said I saved .28 gal
The average is .35 gallons.

This .35 gallons was saved over about a 3.1 hour trip,
or about .35/3.1 = .11 gallons per hour.

A gallon of Exxon 87 octane weighs 6.16 lbs per gallon.
So I saved .11 gal x 6.16 lbs/gal = .70 lbs gasoline per hour

A rough rule of thumb is that on average a engine will use between 0.40 and
0.65 pounds of gasoline for each horsepower that is generates per hour it
runs. This is called by engineers the "Brake Specific Fuel Consumption", or
BSFC.

Picking 0.55 lbs fuel/hp-hr as a part-throttle average -

.70 lbs fuel/hr divided by 0.55 lbs fuel/hp-hr = 1.2 horsepower for the fan
======
"Jeff T" writes about:

>It would seem to me that the greatest benefit would be seen in "city" driving
>where all the cooling is achieved via fan operation. In fact, I would
estimate >that a good 70-80 percent of a fans "work" is performed at speeds
under >50mph. opinions on it.......?

Jeff, I have only done one quick test in the city.
On a drive I do every morning of 11.3 miles from a dead cold engine start, I
usually get 13.8 to 14.3 MPG.

On Saturday morning I recorded the Oztrip computer readout of miles and
gallons, then went on the 11.3 mile trip. I got 15.4 MPG according to the
Oztrip.
--------
if I were to re-do this test today in 2008
I would try to do it with two vehicles following one another 'convoy' style
similar to the Goodyear test below, because the gain from the fan is so small only a very careful test will correctly measure it.

The right way to do it
Goodyear goes by the book with Fuel Max test
When Goodyear introduced its new Unisteel tires with Fuel Max technology last year, and claimed that they were more fuel-efficient than its older designs, the company invited the press to come to its San Angelo Proving Grounds in Texas and observe an SAE/TMC Type II fuel consumption test, pitting old against new.

In this case, two identical tractor-trailers — a control rig and a test rig with the same powertrain, mileage, horsepower, GCW, tires, pressure, etc. — were fitted with removable, portable fuel tanks, which were weighed before and after identical runs of at least 28 miles at the exact same highway speed. Fuel consumption was measured by tank weight, and the two rigs were compared as a baseline. Three runs, which must produce results within 2 percent of each other, were made. In this case, the two rigs’ fuel consumption figures were consistently within 1 percent of each other.

Next, the test was repeated, with the control rig unchanged, and the test truck fitted with the component to be tested — in this case, the new tires. Over the course of three runs, with results within 2 percent of each other, the test truck had consumed about 7.5 percent less fuel per run.

Claim made, point proved, case closed.

 

That's all fine and dandy if my vehicle was a Dodge Truck and not a Dodge Van. The Dodge Van has many disadvantages for air flow in and around the engine bay.

For starters, the van engine sits in a "dog-house" with very little air circulation around it. The "dog-house" is lined with a thick all around heat shield too. The only real air flow is under the engine. That's one reason why the full size vans sit so high off of the ground. So, driving through town or in the country would really raise the temperature gauge over any Dodge Truck readings. The Dodge Trucks manage engine compartment air for cooling in a totally different way.

One advantage the Dodge vans have over the Dodge trucks is the distance of the radiator to the fan is greater. Having an eFan increases this space for better cooling around the engine since heat really builds up fast under that "dog-house." If the plenum were better adapt on the Dodge Vans, heat would be pushed pull up and off the top of the engine. However, above 35mph, the air flow is opposite that direction. Some people have modd'ed the side body panels above the wheel wells to allow the heat to escape on these vans. Ford has been doing this for years.

Next, the Dodge Vans do not have any real air-dam on the hood. The Dodge Vans have this slim access hood that basically allows access to the dip stick, battery and some fuses.

Jumping a mere 18.86mpg to 19.68mpg doing 70mph is not all that great. Besides, driving a full size Dodge Passenger Van at 70mph is crazy due to the center of gravity being too high. I know, I have a 12-passenger B2500. The gear ratio of the 3.92 rear has a fuel economy sweet spot between 48mph to 56mph.

Dave who has a Dodge Ram Van went from the 16.x-mpg to the upper 19.x-mpg after making the switch to an eFan doing a cross country trip fully loaded while towing.

My van barely breaks 14-mpg on mixed driving and hits 11-13mpg while towing the RV camper.

Just switching to synthetic 5W30 and doing the crank-case breather mod helped the engine work less and breath better. It gave almost a full 1-mpg increase according to my fuel log. The Yokohama Geolander G051 low resistance tires put my fuel economy up to reaching 16mpg on good days.

The rear axle fluid still looks and feels good. I use an eye-dropper to extract that oil for comparison. Chrysler mentions to use 75W90 in that rear for improved mileage.

One thing for these vans is to repack the bearings yearly to keep the friction loses down. The B2500 HD and B3500 HD axles really need this maintenance to ensure smooth rolling.

So, will an eFan help a Dodge Ram Van? In all practical purposes it should. And I do agree, not running a fan while traveling down the road is ideal. Ram-air into the condenser and radiator above 35mph works just fine if no towing is involved. For city driving, an eFan is a must.

The best mileage is a cool engine, warm tranny, cold fuel and a large exhaust.

 

I am getting ready to put an e-fan on my 94 Van.I'm sure it will help.Did the 88 Town Car several years ago and couldn't be happier.Not that the van is a gas hog. I get 19.5 mpg at 70 mph with A/c on and 17.5 mpg pulling a car trailer with an S-10 pick Up on it .I run Amsoil in the engine and figure that with the electric fan and Amsoil in the trans and differential I should be up around 22-23mpg highway.This van has 208,000 miles on it. Motor or trans have never been apart. I did some research on the gas mileage figures that were on the window stickers when these vans were new.The V-6 mileage is the worst.The 5.2 is about 1mpg better and the 5.9 is about 1 mpg better than the 5.2. It actually makes sense because the V8's can pull the van thru the wind alot easier than the V6.And when you get the most power and the best mileage in the same package,it doesn't get any better than that.

 

for those who do wish to experiment without spending too much money
this fan

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

or the electric fans from some Audi's
are good donors to look for
from the salvage yard

 

Actually through some durability testing at an OEM company that benchmarked CFM, Delta-P and flow resistance relative to the heat transfer of eFans, the older style (mid-90's) Ford Taurus twin fan setup provided the best results. I believe the eFan motors for the Taurus were the higher performance Bosch types. Of course this test was done back in 2001, so the Viper setup may be a good choice too and more up-to-date. However, if you can pull a working Taurus unit out of a good bone-yard, you'll be further ahead in cost over the Viper eFan. The Viper eFan though should do well on it's sibling Magnum engines.