Hey all, I am getting ready to do a transcooler bypass on my 2003, and i am figure while I am in there I will replace the radiator too.
I am looking for an aluminum radiator that will fit directly into the OEM location, but I do not want anything that is setup for a transcooler. I mean it makes sense right? Why have the transcooler setup if the transcooler is not going to be using the radiator anymore.
Anyone know of a good aluminum radiator replacement that is not setup for the trans cooler.
Thanks for the help!

 

I picked one up off Amazon that had excellent reviews about 9 months ago. It's set up for the oil cooler and trans cooler, but I just don't use that function in the radiator. I run an aftermarket plate oil cooler for the engine mounted beneath the radiator, and an aftermarket oil cooler mounted in front of the radiator.

I run those inexpensive aluminum radiators and my Jeep CJ7 with a small block Chevy, and in my 1990 f250 with a 7.3 diesel. It's been in the Ford for almost 10 years, and in the Jeep about 5 years. No issues with them at all, and they do work a hell of a lot better than OEM plastic garbage. I suspect the tig welds were done robotically... Or else there's one welder in China who really knows his stuff. (And I do welding, and it's better than what I could do.) Pay attention to the reviews. I wouldn't even look at one that had less than 200 five-star ratings.

 

I bought this one from radiator express. Super fast shipping, all aluminum, 2 1/4 core thickness(more than double oem). Couldn't be happier. It has the trans and engine oil coolers but you can simply just plug them. There is no downside of having them in the radiator if they're not connected. Whatever you decide on just get rid of that plastic junk.

Also a little secret is that the escalades, silverado's and hummers from pretty much all years after 03 share the same radiator if i remember correctly.

https://www.radiatorexpress.com/prod...0/1441629#tabs

 

Hey thanks Gavin and Robert!
I havent heard about the engine oil cooler bypass.... could you tell me what radiator to get to do the bypass, or better yet, if there is a set by set on the HUMMER Forums that tells you what to buy and how to do it.
Do you happen to know where I can get the proper plugs for the oil cooler and engine cooler lines?
Lastly, i understand that once they are bypassed the area isnt used anymore by oil or trans fluid, so with that said, I would assume that there is nothing that runs through that area of the radiator any more? is that correct? Basically what I am saying is that originally the coolant, oil, and trans fluid were all cooled by the oem radiator, and each fluid was kept separate from each other. So when saying that it has to be considered that a new aluminum oem radiator with oil and trans cooling features would be separate also... so with the oil and trans by passed, then I would assume that the coolant only flows through a portion of the radiator, and not the whole thing (since the whole radiator is actually used for three different fluids, not just one) ... is that right?
Just thinking if I do the oil bypass too, then maybe I could get away with a radiator that might be slightly different size than oem
Thanks for any help

 

Some of us run an external oil cooler and an external transmission cooler totally separate from the radiator. The main reason is if you develop a leak internally in the radiator, by the time you discover coolant in your transmission it's too late. Same thing for your engine. You'll notice it when you lose oil pressure. If you're going that route, you don't need to plug the lines off where they go into the radiator. You can just leave them. You will want and aftermarket engine oil cooler. I have the plate style mounted directly below the radiator. Works quite well. I used an adapter from Derale that attaches where the factory oil cooler line connects. This allowed me to use braided stainless steel 10AN oil lines.
For the transmission cooler most people run one of the true cool transmission coolers. Mounted in front of the AC condenser and get rid of the small OEM one that's there. Many combinations possible, you can use a smaller one hooked in series with the OEM One. Your choice. I picked the transmission cooler that uses 6AN connections, to match the 6AN fitting I have at the end of the hard line coming from the transmission.

 

 

common misconception. The oil and trans fluid does not run through the entire radiator. Only coolant goes through the core the tubes and little fins are. In each end tank there is essentially just a tube with an inlet and an outlet for the oil coolers and coolant flows around the tube. It’s largely ineffective and really does more warming than cooling.


Here’s is a video of someone taking it apart:

I would advise against just bypassing these unless you have an aftermarket solution like a trucool 40k transmission cooler and another solution for the engine oil cooler. Both will need to be custom. Though it isn’t hard. There are a few guides on the forum if you search.

personally. I have a 40k for the transmission and I left the engine oil cooler in the radiator because the new aluminum engines need a higher oil temp to prevent piston slap. I did switch out the leaky factory lines with some custom ptfe -an hoses.

if I remember correctly I think I posted a guide on either the engine oil lines or the transmission cooler and lines on my account.

 

I considered using compression fittings to -AN coming off the factory hard lines for the engine oil, but I'm not too excited by the OEM connection to the oil pan. That's why I went aftermarket with something more solid.

I was surprised how much better the aftermarket plate style oil cooler mounted under the radiator works versus the OEM. Granted, the OEM sort of preheats the oil for a faster warm up I suppose. But I've got the iron block 6 liter which prefers oil cooler than 210°. On a 75° ambient Air temperature day, 65 mph on level freeway I run 170 to 175° eot. My transmission definitely takes longer to warm up, and under the above conditions settles between 150 and 160 degrees.... Pretty much where our 2014 Escalade runs in the same conditions. But I absolutely don't like the idea of developing a leak and mixing transmission or engine oil with the coolant and the disaster that results.