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Looking on EBay for a new radiator I see the three row radiators are about $600 and the two rows going for around $200, is there much difference between the two? And which kind is my original a Dodge radiator? Thanks
 

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A 2 row will cool better than a 3 provided the rows are 1.25. The more rows, the smaller they are.
 

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Thanks, I was about to start asking the stores about total thickness. My old Chevy two ton has one that’s at least 3” thick and it stays super cool on the hottest days going uphill.
 

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Oem was a real 3 row copper n brass 45lb unit .
I just pulled one out , very heavy .

If you tow , get the three row .
I just put in a 185$ China cheapie don't know the rows ,,, this 94 is around 450 hp and just a bomber truck . Never the less with the ac on and full throttle runs , temp never goes up .

Hope this helps , choice is yours .
 
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2 beats 3 doesn't really calculate out mathematically to me. Because the distance the fluid travels while in the radiator 1/3rd again as long and the amount of air traveling thru the fins remains constant between both then it makes sense that the liquid would cool to a lower temperature before exiting the radiator. Not sure how bigger fins would help cool things more, please school me.
 

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When a 2 row radiator is used, the incoming air hits the first set of tubes, cools the liquid, as it passes it takes the radiant heat, and then hits the 2nd row of tubes, picks up more radiant heat and then passes out of the radiator.

Now add the 3rd of tubes, the air is hotter and exits past the radiator.


I just copied the one above to show how/why 2 rows (hence larger tubes) cool better, there’s plenty more.
 

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I’d rather have a radiator that’s a 2 core of 1.25” than a 3, 4 or 5 row radiator because they will have smaller fines for the same thickness of the core and slow down in coming air.
 

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I have been schooled! I didn't even think about the tubes being larger in the 2 vs 3 situation. It does also make sense that if the fins are smaller and more condensed then there could be air flow restriction thru the radiator. Thanks for taking the time to teach me something. 65 years old and learning new things still!(y)
 
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Don’t sweat it, I damn sure DON’T know everything. I’m about 20 years younger than you and still call my dad when I can’t figure something out, always learning.
 

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Discussion Starter #11
Oem was a real 3 row copper n brass 45lb unit .
I just pulled one out , very heavy .

If you tow , get the three row .
I just put in a 185$ China cheapie don't know the rows ,,, this 94 is around 450 hp and just a bomber truck . Never the less with the ac on and full throttle runs , temp never goes up .

Hope this helps , choice is yours .
24hrsparky, my shop manual says the two bigger engines, like the 10 valve, came with copper radiators while all the others including my 5.9 Cummins came aluminum. Doesn’t mention number of tubes. I don’t know if mine is original Dodge but it’s 2 1/4” thick and that’s what the one I just ordered was, it was 185 including shipping and 2 hoses, I’ll let you know in a couple of weeks if it’s working good. Thanks everybody for all the great thoughts
 

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A 2 row will out cool a 3 row. The more rows, the less efficient the last row(s) are.
Uh.......no. When my original 3 row started leaking I bought an OEM replacement. Dodge had changed to a 2 row radiator, which was also a different metal composite. It did not cool even as close to well that the 3 row did. I tried an internet aluminum 2 row. It wasn't any better. I bought an Ice box 4 row. I don't have any issues now with cooling with the heaviest of trailers, in any environment or in the mountains. I put it to the test yesterday on Hwy 97C between Kelowna and Merritt, B.C pulling an 8000 pound TT. That highway is 20+ miles of 7 to 8% climb. With the AC on, 80f outside temp I never exceeded 190 at 50 mph. Your theory doesn't hold water.
 

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Uh, yes it will! What size was the tubes? If they are smaller than what’s in a 3 row, then no it won’t.

I’ve built a few BB Mopars and always use a 2 core aluminum radiator with minimum 1.125 tubes, better is 1.25 tubes, also NO Chinese radiators, Griffin, BeCool etc.

Brass/copper will cool better than aluminum, but they are a softer alloy and so the tubes can’t be made as big as aluminum.

Find out for yourself, read what ya find and you’ll be surprised at what works. Not trying to be a$$, just trying to show you what I’m talking about.
 
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A 2 row will out cool a 3 row. The more rows, the less efficient the last row(s) are.

It's not that simple..

A 2 row rad with 2x 1/2" tubes will absolutely NOT outcool a 3 row rad with 3x 1" tubes.
You have to take the core thickness into account.

The brass/copper rads are superior to aluminum rads but they are much heavier and more expensive to manufacture than aluminum.
Hence why all OEM rads are aluminum these days.
 
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Find a 3 row 1inch tube radiator that is not custom built that’ll be a direct fit to replace the factory radiator. You won’t cause you have 3 inches just for the tubes alone.

And by the time air hits the 3rd row, it’s really not doing anything cause the air is hot.

Read what i wrote, then do your research. We are talking about the SAME size tubes, not smaller and less tubes to larger more tubes.
 

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I can attest to the better cooling of a bigger tubed 2 row Radiator
at first i was skeptical since i knew my OE was a 3 row I live in Arizona where 118* ambient air temp is not uncommon
and on the road the radiated heat can be 150 + deg
well the newer 2 row Radiators have way bigger tubes in them they Dimensonally are the same size as the OE
in addition they are made from aluminum they cool extremely well as opposed to the OE Copper and brass ones
1 800 radiators here in Tucson has them for 155 bucks
 

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I just copied the one above to show how/why 2 rows (hence larger tubes) cool better, there’s plenty more.
I read the link and it makes sense to a point. What it doesn't take into consideration is total coolant volume. If the 3 row has more coolant than the 2 row it will flow slower and have more time to cool. Fin count also plays a part. The more fin contact per row the better, up to a point. You don't want them so thick air flow starts to suffer.

Part of our 2nd gen cooling issues are related to the bumper design. The license plate holder blocks the flow. I would like to do a 4th gen bumper, way more air flow at that location. I have been dealing with overheating for the past 5 years, since the Edge Juice install. So I read most of the overheating threads trying to get answers. I do realize the system is too small for 400hp/900tq, towing at 26k gcw and not Dodges fault.

My next mod is a early 2nd gen fan clutch, they match the oem 180 t-stat. I do run a 180* but my '01 oem fan clutch is matched to the oem 190*. It engages too slow, about 200-210 depending on how quick the temp goes up. My '91 comes on at about 190* so I ordered one.
 
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Discussion Starter #18
Where did you order your early fan clutch from? That sounds like a winner. I didn’t know about the bumper either. The fin count being not too high makes sense too.
I’ve read a few opinions here about increasing or decreasing flow rate being good but it seems to me that the flow rate should be whatever the thermostat puts it at, and no farther restriction by the radiator is desirable. A radiator with more flow can’t increase the flow rate that the thermostat restriction gives. So therefore it can’t hurt to have high flow in the rad., just done want it any less than what’s at the thermostst
 

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Where did you order your early fan clutch from? That sounds like a winner. I didn’t know about the bumper either. The fin count being not too high makes sense too.
I’ve read a few opinions here about increasing or decreasing flow rate being good but it seems to me that the flow rate should be whatever the thermostat puts it at, and no farther restriction by the radiator is desirable. A radiator with more flow can’t increase the flow rate that the thermostat restriction gives. So therefore it can’t hurt to have high flow in the rad., just done want it any less than what’s at the thermostst
I assume you have a 12 valve? If so, you have the 180* stat and fan clutch. I think the 190* system started in 2000.
 
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