7.3 Ford fan swap

[Jslay]

Hey guys, just curious about this fan swap. I live in East Texas and summer is brutal here. I'm having problems keeping normal driving temps below 210. I have 2 10" pusher fans on condenser, 180° thermo, fresh rad juice and flushed. I also replaced condenser 2 aluminum ac lines and orifice tube, dryer. And vent temps are 67°. I don't hear fan clutch kick on and it has been replaced as well last month. My question is, is mechanical fan worth it? What about winter months trying to heat up ?

 

[AH64ID]

Specs on the truck?

 

[Jslay]

Specs on the truck?

04 2500 4x4 300k

 

[AH64ID]

That generation truck came with a 190° thermostat and the fan is programmed around that.

The thermostat cracks at 190°, goes full open at 207°, and usually runs 215-217° when pulling hard on hot days. The fan starts to really ramp up around 215°.

I would swap the 180° thermostat out for a genuine Cummins 190° thermostat and see how it runs with the other new stuff.

The problem with the 180° thermostat in this truck is that its max allowable temp, per Cummins, is 212° so you are above that by the time the fan kicks in. You can reprogram the fan, but unless you already have custom tuning it’s cheaper to run what it’s designed for.

What brand fan clutch did you get?

How old is the radiator?

Do you hear the fan with the A/C?

What are you using to see exact coolant temp numbers?


As for the mechanical conversion, no I wouldn’t recommend it. It’s an antiquated design that isn’t used anymore for a reason.

 

[Ozymandias]

I second this, it's no sense to try to keep the engine at a lower temperature then it is designed for to run all day long.

If it runs away above 220° you might need anew fan clutch as it ages like the old style ones and the rpm come down somewhat.
If the gap between demand and actual fan speed gets to big ut will set a fault code and lite the CEL.

 

[Jslay]

Haven't replaced radiator. I got this truck a year ago and don't know much about it before that. Clutch is the second one in a year from AutoZone. I don't hear it when ac is on.

 

[Jslay]

I flushed and did Thermo to get it down to 210 but before that it would get to 216. I use my generic code reader to read live data for temp.

 

[Ozymandias]

....and the fan clutch doesn't "kick on" at all, it comes on softly to the speed the ECM demands and fads out smooth if command that way, most of the time you don't hear it at all. It needs to be really hot that the fan goes to 100% speed.

 

[Jslay]

So throw a radiator and 190 Thermo at it and good or works out?

 

[Ozymandias]

216 is great! That's what it is built for.
You spent a ton of money for nothing.

The newer the engine the hotter they run, this isn't like previous engine generations. The emissions demand a hot engine, if you run it at 180° the ECM tries hard to get it up to 190°, still in cold start mode, wasting fuel trying to get the engine to operating temperature.

 

[Jslay]

My local mechanic was telling me it shouldn't get over 200 unless towing heavy loads

 

[Ozymandias]

Coming to the AC, you say 67° at the center vents, fan at 3/4.
In Recirc mode after 15 minutes driving time?

 

[Ozymandias]

My local mechanic was telling me it shouldn't get over 200 unless towing heavy loads

He is wrong if it comes to this truck and model year. Sorry
A couple years, or decades by now, he was right, but that's a long time ago.

 

[Jslay]

Coming to the AC, you say 67° at the center vents, fan at 3/4.
In Recirc mode after 15 minutes driving time?

Yes. I filled according to pressure and temp. 100° outside, 55 low side and 260 high side. About 40-42oz

 

[AH64ID]

Ditch the autozone clutch for a mopar one.

Get a new radiator and 190° thermostat.

Fan should be roaring at 216°.

My local mechanic was telling me it shouldn't get over 200 unless towing heavy loads

He doesn’t know much about these trucks. The OE thermostat isn’t even fully open until 207°.

 

[Ozymandias]

Yes. I filled according to pressure and temp. 100° outside, 55 low side and 260 high side. About 40-42oz

Greatly overfilled, it takes about 18.5oz or 1.14lbs for the factory fill.

That's the next, you can not fill that AC by pressures.
No one knows why but the low side is always really "low" on a fully functional system.
You see number like 25/300 on your vehicle.

Fill it strictly by weight and you'll see 45F and lower from the dash vents.

 

[Jslay]

Well thanks guys. Now I get to convince my wife I need more parts. Any suggestions on rad brands. I have mishimoto for my imports but they are expensive.

 

[Jslay]

Greatly overfilled, it takes about 18.5oz or 1.14lbs for the factory fill.

That's the next, you can not fill that AC by pressures.
No one knows why but the low side is always really "low" on a fully functional system.
You see number like 25/300 on your vehicle.

Fill it strictly by weight and you'll see 45F and lower from the dash vents.

I'll try that tomorrow after work. That's seems pretty low but I have plenty of 134 in shop.

 

[NIsaacs]

Well thanks guys. Now I get to convince my wife I need more parts. Any suggestions on rad brands. I have mishimoto for my imports but they are expensive.

Any of the local auto parts would be fine for a stock unit. If you want more, this link has several to choose from.

https://www.radiatorexpress.com/part-lookup/radiator/dodge/2004/ram 2500/base/59l-l6#

Fan clutch.

https://www.genosgarage.com/product/52028879af/fan-clutch

Thermostat.

https://www.genosgarage.com/product/ram-cummins-thermostat-5292744/thermostat

 

[Ozymandias]

Factory radiator is just fine and good for all situations.
W8th aftermarkt check for the thickness. More then often they are thinner.