2004 Dakota Sport Plus Quad Cab AWD 4.7 Auto
Originally equipped with "Heavy Duty Engine Cooling".
According to Dodge it came with 55056518AA, which is discontinued.
Parts guy at dealership couldn't tell me whether this radiator came with internal trans oil cooler or not. He recommended OSC 13337 as equivalent replacement. This does have internal trans cooler.

Current (leaky) radiator does not have internal trans oil cooler. There is an external cooler in front of radiator. The cooler and lines setup looks very original--it doesn't appear to be an aftermarket add-on. I don't know if truck came this way, or if someone modified it (likely with parts from Dakota model that did have external cooler as it looks so "native"). But... this truck had about every option available added (I'll attach build sheet)--wouldn't an external cooler have been considered an upgrade over an internal one?

I can't find a "heavy duty" radiator (ie core thicker than standard 1.25") online that clearly doesn't have an internal cooler--either they indicate they have cooler, or there is no mention of it. Does anyone know of such a beast (thicker than 1.25" core that doesn't have internal cooler)?

To further complicate matters, the current radiator is only 1.25" core. So this beggars the question: do the HD rads (thick core) mount the same as 1.25 core ones? Seems if I'm replacing radiator I might as well get HD one, but if they are only available WITH internal trans cooler should I proceed? Should/can I just ignore the internal cooler and continue using external, or should I do what's necessary to use internal?

Apologies for being so wordy, but I'm likely going to have to order this online so I won't be able to inspect it first, and it will cost a lot to return it, so trying to do as much as I can to choose right part.
Thanks

 

Trans cooler is likely part of the Towing group option package. If your trans cooling isn't plumbed thru the radiator now, then there likely isn't a need for the additional cooler when you replace the radiator either. So, if you find one you like, that has the internal cooler, you can just ignore that particular aspect of it. If you can, see if you can find an all-metal radiator. (no plastic tanks....) They tend to be more efficient.

 

https://dodgeforum.com/forum/2nd-gen...-radiator.html

 

The only all-metal ones I could find were the "3 row core" ones that are all over Amazon. Anyone have experience with those? I've read that 3 rows isn't necessarily better than 2, can be worse, but core is thicker than the other exact fitment HD options, so thinking it might still cool better? I'm a bit skeptical, but I can at least return it for free if it looks like junk after receiving, or if it looks like mods required to fit are more thanI want to tackle.

 

That actually looks pretty good. Good fin density, welds don't look too bad.... You can use the internal trans cooler, or not. Up to you.

 

I've read others advise that the internal trans cooler should be used in addition to an external because trans fluid might be over-cooled by external cooler, ie running trans fluid through radiator will raise it to appropriately high running temp in very cold weather. I'm not sure I buy that. It might help the fluid initially get to warmer temp sooner, but does an auto trans benefit from that?

 

Theoretically, too cold is almost as bad as too hot...... Or, so I have read. But, isn't there a thermostatic valve on your cooler lines somewhere????? I thought the 'newer' trucks had one...

 

Yes, that's exactly why the internal "cooler" is there. It's actually a warmer which bring the fluid up to temp fast on cold starts. The external cooler does the cooling.

 

The mopar parts manual shows only 2 options for the cooler lines. These are presumably for external cooler or internal cooler. Image search for part #s confirms they are long, trans to cooler lines. If the external cooler were run in conjunction with an internal cooler from the factory there would be a short line that ran from internal to external cooler listed--there is none. Furthermore, an examination of my current lines shows what appears to be prefabricated lines that go directly from trans to external cooler. Both lines are different, with different prefab bends and length, and both fit precisely. Neither of the lines would properly mount to either port of the internal cooler. IOW, these lines were designed to take fluid from trans to ext cooler and back with no provision for routing to internal cooler. It appears at least 2004 models were designed to run either internal or external coolers, not both. I suppose it's possible that the parts manual is not completely inclusive and some were shipped with both coolers utilized, but it certainly doesn't appear to be the norm.

 

No valve. And I strongly suspect this was designed to run ext cooler only (see my response above). Has 230k and still running strong (knock on wood), and I rarely run in temps far below freezing, so think I'll just leave it as is.