Couple of months ago I bought a 2004 Dodge Dakota SLT V8 with 155k miles from a crappy little used car dealership. The stock ( I think) transmission cooler was leaking because the guy said he pushed another vehicle with the Dak and it bent in the grill and bumper and also messed up the cooler. Before this purchase I was driving an 02 Dak 3.9.

I bought an aftermarket universal cooler from Napa and installed it. I noticed that unlike my 02 3.9, the 04 4.7 had a separate cooler, and the cooler lines did not go in or out of the coolant radiator, even though the 2 rads are 100% the same. There are 2 stoppers screwed into the 04 rad where the lines go in and out of the 02 rad.

The vehicle specific trans cooler was $200+ from Napa, and had the installation bracket with it. I simply just installed the new universal cooler on the front of the ac cooler.

My question is.. In the 04, is the coolant rad avoided by design from Dodge? Should I have run it through the coolant rad first, then to the universal one? Also, I purchased a new trans cooler with an electric fan.. Should I link this one in or should I replace my universal from Napa, and should I run it through the coolant rad or not?

Thanks in advance for any help. I searched the forums but if I missed an answer in this my apologies.

 

I've got the 03 SLT with tow package. Yours must have the tow package as that includes the external cooler. I replaced the radiator 7 years ago and I don't recall any tranny lines going to it. Just to the cooler, I believe. Can look tomorrow and let you know. Here is a pic of the external cooler.

 

Thanks for your response! The one you have pictured is the one that was leaking, and priced around $200 at local brick and mortar auto places. I took it out completely, and installed a universal one.

I'll take pics of the universal I installed, tomorrow morning. My SLT has the tow package as well. I'm curious, what tow electrical connector came with yours? Mine has a round one, I'll again check in morning which one exactly.

 

On my 2000 a line goes into the radiator cooler, out to the external cooler then back to the trans

 

 

all factory tow package are 7-way round.

 

Thanks, but I wasn't sure if it was factory or if prior owner put it in, because there's also a Hayes Lemmerz trailer brake controller installed under the dash.

Anyway here's what I'm thinking, please let me know if it doesn't sound like a good idea. I live in northern New Hampshire, where it gets pretty cold for months at a time. The current setup avoids the coolant radiator, but from what I've read, when the trans fluid travels through the ("heat exchanger"?)... that actually helps to get the trans fluid warm when it's really cold, at startup.

I'm thinking to change it to include the coolant rad, then through the universal I currently have installed, then through an additional universal with an electric fan connected.

This way, the trans fluid can warm up quickly in the winter, but stay cool in summer and while towing/etc....

 

Trans fluid heats up faster than the radiator does. If you let it just sit and idle, than yeah, coolant will warm first. That said.... running it thru the radiator cooler will keep the temp more stable.... Being you live where it gets COLD!!!..... I would be tempted to install a thermal bypass valve in there, so you bypass the external coolers below about 190 degrees.

 

Took a look today.

Was kinda difficult with the shrouding in place, but I was able to see a line running from the radiator to the cooler. It attaches to the cooler where the green arrow indicates, loops around to the back and enters the radiator just over the bottom hose. So this confirms that the radiator's heat exchanger is being used in series with the cooler. If you have the ability, go ahead and hook it up the heat exchanger, but if not, HeyYou's idea of a thermal bypass is a good one too. I had forgotten about those. They won't allow coolant to flow into the cooler till it reaches a certain temp. Another route is that most coolers come with plastic zip anchors that allow you to anchor it directly to the radiator, so the heat transfers right to it. Don't think that's possible in your case though.

I wouldn't use two universal coolers. Too many failure points to spring a leak and toast your tranny... and there is such a thing as overkill. Just find one decent sized ATF cooler and make damn sure there are no leaks when you're done.

And....there is always ebay....
https://www.ebay.com/itm/2004-DODGE-DAKOTA-Transmission-Oil-Cooler-23-X-5-COOLING-FINS-SIZE/124180470527?hash=item1ce9bb9aff:g:0xYAAOSwZ19etYT K

https://www.ebay.com/itm/2003-DODGE-DAKOTA-TRANSMISSION-OIL-COOLER-3-9L-OEM/323790087503?hash=item4b6364a54f:g:eowAAOSwRG1cw5p u

or https://www.partsgeek.com/gbproducts...iABEgL5hfD_BwE

 

You want the route to be trans out, aux cooler, rad cooler then trans in, to keep a stable temp on the trans fluid. The trans wants to see a temp range, and a stable temp. Too cold and it will shift harsh, cost mileage and wear too fast, too hot and it will burn up. The rad cooler will make sure that if the aux cools the fluid too much, that the fluid is warmed back up to the ideal range. This is how the OEM routes aux coolers, and they do use aux bypasses on some makes.