Spectra Premium from Napa has been fine for my uses. I’d prefer Mopar but I’ve run the Spectras with no issues at all.
Best aftermarket radiator now that OEM are all gone (2004 4.0)
- Thread starter SeizeTheKarp
- Start date
OP
im sure itll fit. im curious if there is a chance that the unused connections for the auto trans will leak.
There's nothing in them to leak out. It's a separate cooler.
OP
I can't see why you couldn't but I'd wait for a more knowledgeable member to chime in on that.
Not really but you cap them off if you want. I don’t use the cooler in mine and it’s been fine.
Knowing Wermopar it'll likely say it's out of stock if you dig a little deeper. Everything I have looked up there for my TJ in the last several years showed in stock until I dug deeper or tried to order it.
Not in the least, the transmission cooler and radiator are completely separate from each other. You can cap or leave the cooler fittings open. An unused transmission cooler could be used for something else like a power steering cooler.
I have a theory (obviously no hard evidence to support it though) that the biggest reason that the aftermarket “performance” radiators fail is not because of coolant pressures or temperatures, but more simply just flex in the body.
If you look at the radiator and the A/C condenser, they have very different mounting systems. The A/C condenser is mounted with the use of rubber isolation mounts which allow a small amount of movement between the grille and the condenser. However, the radiator is directly bolted to the grille.
The OEM radiator is probably designed for a certain amount of flex, or at least happened to pass testing. The aftermarket designers may not be aware of this, and simply adapted their other (otherwise successful) designs to the TJ.
If this is true, I would suspect that adding flexible mounts to an aftermarket radiator would significantly increase the lifespan of that radiator.
Another (similar) idea could be that the aftermarket radiators do not have adequate flexibility to accommodate the thermal expansion and contraction from routine use, and simply develop cracks and eventually fail instead. Essentially, as the radiator heats up, it expands, but the grille it is bolted to is the same size. Thus, the two end up imparting a lot of stress on one another, and the radiator, being made in part or wholly with aluminum, fatigues and eventually pops.
If I had to choose an aftermarket radiator, I actually would try one of the name brands like Mishimoto. But I would 3D print some flexible rubber mounts rather than mount it using the OEM bolts. More generally, I would make sure that it is free to flex in any direction, be it caused by thermal expansion, body flex, or even just vibration.
If you look at the radiator and the A/C condenser, they have very different mounting systems. The A/C condenser is mounted with the use of rubber isolation mounts which allow a small amount of movement between the grille and the condenser. However, the radiator is directly bolted to the grille.
The OEM radiator is probably designed for a certain amount of flex, or at least happened to pass testing. The aftermarket designers may not be aware of this, and simply adapted their other (otherwise successful) designs to the TJ.
If this is true, I would suspect that adding flexible mounts to an aftermarket radiator would significantly increase the lifespan of that radiator.
Another (similar) idea could be that the aftermarket radiators do not have adequate flexibility to accommodate the thermal expansion and contraction from routine use, and simply develop cracks and eventually fail instead. Essentially, as the radiator heats up, it expands, but the grille it is bolted to is the same size. Thus, the two end up imparting a lot of stress on one another, and the radiator, being made in part or wholly with aluminum, fatigues and eventually pops.
If I had to choose an aftermarket radiator, I actually would try one of the name brands like Mishimoto. But I would 3D print some flexible rubber mounts rather than mount it using the OEM bolts. More generally, I would make sure that it is free to flex in any direction, be it caused by thermal expansion, body flex, or even just vibration.
OP
Awesome. Sounds good. it seems a no brainer to try making use of an unused system
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Don’t forget that the heat exchanger also acts a heater. So it will heat whatever fluid moving through it to the coolant temperature, which might be a bit higher than ideal for a power steering system.
Overlanders often use it as a domestic water heater.
OP
That kinda makes sense. Normally atf would be hotter than the coolant temp so running it through the radiator would cool it but power steering fluid ( which is still atf in this case) might not be that hot so the radiator could end up making it hotter?
Mishimoto did actually address the hard mounts a while back and they now have rubber isolated bolt sleeves, I'll be 8 years on my Mishimoto next month with the original hard mount.
Interesting…
Might actually be worth a try then. I’d be curious to see how well they are isolated.
OP
Well i guess this was not the case because it is now sitting in my living room. Also have a oem thermostat and fan clutch from them on the way said they were in stock and shipped this morning
Happy in Montana
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