2004 TJ 4.0 Straight 6 Radiator

Cedarhouse

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Redlands Ca
My 2004 TJ 4.0 straight 6 engine's radiator is blown open at the top (Plastic) What is the correct part number for this radiator? Just get it at AutoZone? Also, Will a 4 row fit or should I even use a 4 row? Is an aluminum radiator better? Live in Redlands Ca
 
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You didn't mention whether you have an AT or MT, but here are the OEM PNs (55037 652AA, 653AB or 654AB) for your year TJ 4.0L.


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Good luck finding an OE one.

I, and many others, have had good results with Denso radiators. There are some other decent ones out there too. I’ve had good luck with Denso radiators in my Jeep and many many other vehicles as well. Do NOT mix coolants. Make sure you flush out ALL old coolant before refilling unless you know FOR SURE what’s in there.
 
A little light reading...


-Mac
 
Good luck finding an OE one.

I, and many others, have had good results with Denso radiators. There are some other decent ones out there too. I’ve had good luck with Denso radiators in my Jeep and many many other vehicles as well. Do NOT mix coolants. Make sure you flush out ALL old coolant before refilling unless you know FOR SURE what’s in there.
Mac like this even though the last time he recommended Denso I posted a link to the thread about the gent who lives very near to our OP and all of his struggles with the poor performing Denso in our part of the world. Mac should know better and he should be posting that link so folks who live where it matters won't try to use that piece of shit.
 
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I've got a Napa sourced Spectra my previous owner installed. I've replaced just about everything else in my cooling system. So, agreed,no personal experience with Denso.

That being said it appears that most folks are happy enough with them...and the cost is low enough it's not unreasonable to throw one or two at the Jeep.

@mrblaine is correct about that post.

Really wish there were better solutions and it would be lovely to crowd source data points rather than subjective stories of success or failure.

-Mac

Edit: here is the post I think we're talking about...

 
Really wish there were better solutions and it would be lovely to crowd source data points rather than subjective stories of success or failure.

-Mac

I once had a gent move down here from Washington who wheeled extensively up in that area. He stayed with us a bit and on the second day he mentioned that he was having to drive to the store in the evenings after it cooled down some due to overheating in his TJ with the heater on full blast. WTF? Didn't you have the problem up in WA? No, it was just fine up there with no issues, never ran hot. But, I can't even drive it during the day down here or it goes into the red with the check gauges crap in very short order.

Point being, without location, the crowd source data is useless and leads to recommendations of that Denso piece of shit to folks that live where they need a radiator that actually works and Redlands is one of those places.
 
Point being, without location, the crowd source data is useless.

Exactly why you need hard data points and consistent ones to do any scientific or statistical analysis. Ambient temperature, coolant temperature before and after the radiator. Underhood temperatures. Engine data like RPM, timing and exhaust temperatures. Airflow. Altitude. Probably just getting started listing data points.

Probably all breaks down to delta...

The magic of the original Mopar radiator that lasted 15 plus years seems to be lost to time.

Same issue with crosscut saws...we use the old ones from the 1890s to 1930s because they hold sharpness for a few seasons. New saws need sharpening every outing and sometimes every log. When chainsaws came out everyone discarded the knowledge of how to make those original saws.

-Mac
 
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Exactly why you need hard data points and consistent ones to do any scientific or statistical analysis. Ambient temperature, coolant temperature before and after the radiator. Underhood temperatures. Engine data like RPM, timing and exhaust temperatures. Airflow. Altitude. Probably just getting started listing data points.



-Mac
Nope, you don't need any of that shit. All you need is location, a reasonable understanding of the area's heat demands placed on the system and then what radiator is working and you need more than a statistical sample of 1.
 
Nope, you don't need any of that shit. All you need is location, a reasonable understanding of the area's heat demands placed on the system and then what radiator is working and you need more than a statistical sample of 1.

What radiator has worked for you , in your part of the world ? ( I will go out on a limb with this statistical sample of one ) . Thanks.
 
What radiator has worked for you , in your part of the world ? ( I will go out on a limb with this statistical sample of one ) . Thanks.
We've worked on more than a few dozen TJ cooling systems. We have a 100% success rate with all Mopar parts. We have worked on a few rigs with other than Mopar, 1 of the 3 was fine after several years. The 1 was the 2nd non Mopar radiator in the same rig, the 1st one failed miserably, the 2nd worked but no one should ever run it because it is or was retarded. It was designed and built in a rig that didn't have AC. They pushed the core into the space taken up by the condenser so if you ran it with AC, you had to space the radiator back. If you spaced it back, then you couldn't install it with the grill in place.
 
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My original radiator blew it's top a few months ago. I ended up replacing it with a Denso radiator from Rock Auto.

My TJ is MT. Radiator was for an auto but still works fine. I did leave the plastic shipping plugs in the tranny cooling line ports.

No problem keeping my TJ cool this summer in the NV desert.
 
We've worked on more than a few dozen TJ cooling systems. We have a 100% success rate with all Mopar parts. We have worked on a few rigs with other than Mopar, 1 of the 3 was fine after several years. The 1 was the 2nd non Mopar radiator in the same rig, the 1st one failed miserably, the 2nd worked but no one should ever run it because it is or was retarded. It was designed and built in a rig that didn't have AC. They pushed the core into the space taken up by the condenser so if you ran it with AC, you had to space the radiator back. If you spaced it back, then you couldn't install it with the grill in place.

Thanks ! It doesn't surprise me that a MFG. would build a radiator incorrect. But thanks for the heads up . I wonder if they built 2 different radiators for
A/C vs. non A/C applications ? It seems odd that they would if the cores were the same thickness . Additionally , if the A/C core cooled properly , why the hell build something different for non A/C apps ? Thanks for your desert cooling views Blaine.
 
Thanks ! It doesn't surprise me that a MFG. would build a radiator incorrect. But thanks for the heads up . I wonder if they built 2 different radiators for
A/C vs. non A/C applications ? It seems odd that they would if the cores were the same thickness . Additionally , if the A/C core cooled properly , why the hell build something different for non A/C apps ? Thanks for your desert cooling views Blaine.

Northern Radiator
 
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