Aftermarket Cooling for Engine/Transmission

Anybody know of any after market or Mopar cooling add ons for a 2004 Liberty 4x4?

I don't have the towing package so how do I get the bigger radiator fan?

How hard is everything to hook up?

Ryan

The bigger fan is really just a seconday cooling fan that happens to be mechanical. You can buy the HD cooling package from a dealer (or at leat I think you can)

Not sure what to do on the transmisison cooler though... TJKJ or someoen will have some good insight.

The trans cooler should be easy to add, just need to do some plumbing to route the trans cooler lines to it instead of the stock one built into the radiator. Do a little searching online and you will find a few companies that make aftermarket trans coolers for the KJ.

I thought about adding the HD cooling but it doesn't get hot enough to justify it, i hauled my utility trailer yesterday with a pretty full load and it never got any warmer than usual. Plus if you add the mechanical fan your sucking away horsepower to turn it.

kb0nly said:

The trans cooler should be easy to add, just need to do some plumbing to route the trans cooler lines to it instead of the stock one built into the radiator. Do a little searching online and you will find a few companies that make aftermarket trans coolers for the KJ.

I thought about adding the HD cooling but it doesn't get hot enough to justify it, i hauled my utility trailer yesterday with a pretty full load and it never got any warmer than usual. Plus if you add the mechanical fan your sucking away horsepower to turn it.

Click to expand...

KJ's with the 45RFE trans only('02 and some '03's) has the cooler built into the radiator,if you have the 42RLE trans you have a stand alone cooler('03+) that can not handle temp spikes in the trans fluid like the in-radiator cooler can.

If you have the 42RLE the best way is to get a radiator for a '02 KJ,swap it in and cut one trans cooler line and attach it to the in-radiator cooler(that is built into the '02 radiator),then run a line from the other in-radiator cooler port back to the stand alone OEM cooler so you now have a in-radiator cooler(to control temp spikes and get the fluid to operating temp faster) and a AUX cooler to help further reduce fluid temps.

The KJ's with the 42RLE transmission had an externally mounted transmission cooler instead of the radiator mounted unit on the 45RFE's used in the 2002and early 2003 models.

So for his situation, I was thinking it would be best to leave the stock external cooler and then add the 2002 radiator with the internal trans cooler tank. This would add secondary cooling to the transmission system as well as provide a much larger cooling platform to control any temperature spikes from the transmission fluid (towing, off-roading, etc.) My only question was on the plumbing work that would be needed since I have a 2002 - I am not sure what the cooler lines look like on the later models... which is why I defered my comment earlier to the more experienced KJ folks..


Another viable option would be the addition hood louvers. Tom and TJKJ both have them (I think a few others do as well) and they seem to pull a LOT of heat out of the engine compartment. Removing all that stored heat would go a long way in enhancing the cooling effieciency of the KJ's single electric fan and the stock trans fluid cooler and radiator. [not that the single fan has trouble currently - but more is better....]



Edit: TJKJ beat me to the post while I was thinking about what to write.

OK. i may be confused but I have a 02 KJ....how can I tell if I have the trans-cooler built in or stand alone?

AMG said:

OK. i may be confused but I have a 02 KJ....how can I tell if I have the trans-cooler built in or stand alone?

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Any KJ with the 45RFE (02-early 03) ****** will have it built in....

ok I guess I have that now what is the mini cooler on the driver side in front of the other cooler? I wonderd about that last night while replacing the radiator.

All 2002 KJ's with an automatic transmission (45RFE) will have the transmission cooler built into the radiator. To verify this, pop the hood - look down the [passenger?] side of the radiator and you'll spot two 1/4" aluminum tubes running into the radiator end cap. This is where your built in cooler rests.

Once the switch began to the "other" transmission in mid 2003, the transmisison cooler was moved out of the radiator as a stand alone unit in the front of the A/C condensor.


Edit: The mini cooler is for the power steering fluid.

Back to the topic of better cooling
to my knowledge there are no after market fans
the best way to cool an engine is good water flow ,water pump working good
T-stat working good and radiator clean on the inside
The best way to cool the water is good air flow ,fan working good and radiator clean on the out side

I had so many cooling issues with my TJ it is unbelievable
the problem was that I was asking to much of the small radiator and restricted air flow with a tummy tuck
Hood vents made up for the TT
removing the trans from the radiator and installing a stand alone cooler with a temp gauge made up for the "just enough" radiator
installing a "pusher" 10" E-fan to help air flow when on the trail ,1200 rpm's does not move enough air with the engine fan even with a good fan clutch
fixing the cracked fan shroud helped the air go where it needed
I can now run the trails in 98* heat and 100% humidity with the AC blowing and still stay at normal road temps

J-Thompson said:

Back to the topic of better cooling
to my knowledge there are no after market fans
the best way to cool an engine is good water flow ,water pump working good
T-stat working good and radiator clean on the inside
The best way to cool the water is good air flow ,fan working good and radiator clean on the out side

Click to expand...

This is about Transmission Cooling issues, not engine... People with the separate coolers can't conform to this information anyway, since the cooler is SEPARATE... Also, there are plenty after market electric fans; you can buy an aux electric fan at PepBoyz, AutoZone, and Advance Auto or whatever major auto chain is in your area. As for placing it? That's another issue.

The best thing to do, IF you want the work: Is buy the older Liberty rad with the trans cooler lines in it. Then run the OEM cooler AFTER the rad as AUX, on the return line - through the cooler, then to the transmission. Heat is the #1 killer of transmissions, anyone with a Chrysler product would know that, at one point in time... I added one to my A604 on the Avenger I has, it has 153k miles on it when traded, no slipping or shifting issues. If I had the time, I would do the RAD swap and use the OEM as AUX cooler for mine... The OEM coolers on the Jeep they use, are a lot larger than store bought AUX, heavy-duty coolers... I had a medium duty on the Avenger, and it was about 1/4 the size of this thing... I could fit FOUR of those on TOP of the the liberty has in it...

Now, with the just the RAD cooler the earlier models got, your temp is more constant, and even. The newer ones with the separate cooler causes temperature spikes, and that's not entirely all that good for the transmission. Still, they made it that way, and warrantied them too, so they can't be ALL that bad...

Making the motor cooler in this case, won't help the new liberty with the front mounted cooler... You would have to add the mechanical fan, at the cost of; loss of to the wheel HP and Torque, to keep air-flow constant on the cooler. You can add a SMALL electric fan, and front mount as PUSH IN, they are water-proof... You can mount it right to the trans cooler of you want.

AMG said:

ok I guess I have that now what is the mini cooler on the driver side in front of the other cooler? I wonderd about that last night while replacing the radiator.

Click to expand...

I think that's the power steering oil cooler.

Powerslave said:

This is about Transmission Cooling issues, not engine...

Click to expand...

I think the point to J-T's post was that the cooling system operates at it's best when the cooling solution is considered as a whole solution and not just a hodge podge collection of parts that don't work together.

So to get the optimal transmission cooling, one should consider the engine cooling performance as well.

sleeve said:

I think the point to J-T's post was that the cooling system operates at it's best when the cooling solution is considered as a whole solution and not just a hodge podge collection of parts that don't work together.

So to get the optimal transmission cooling, one should consider the engine cooling performance as well.

Click to expand...

yup
remember that I put a gauge on my trans so I could see the temp
I know that it was running around 210* when it was going through the radiator and nothing else
now that it put it through the cooler alone under harsh conditions with the AC on and the electric fan on it never goes above 160*
which if you know transmissions this is optimal
when I had it going through both it was running 180-190
so the engine was heating up the trans
cooling every thing separate is much better than both the engine and the trans being cooled by the radiator

Having an electric fan or a mechanical fan I would pick electric only all day
having a mechanical AND and electric is better than just 1 or the other
but a mechanical fan alone will not pull enough air at slow engine speeds
and a crappy electric fan is only good for light cooling like a trans cooler
would need

oh
by the way I just LOVE when people cut 1/2 you post to prove a point
real top notch
if you were to read the second part of the post it all ties in
nice

J-Thompson said:

yup
remember that I put a gauge on my trans so I could see the temp
I know that it was running around 210* when it was going through the radiator and nothing else
now that it put it through the cooler alone under harsh conditions with the AC on and the electric fan on it never goes above 160*
which if you know transmissions this is optimal
when I had it going through both it was running 180-190
so the engine was heating up the trans
cooling every thing separate is much better than both the engine and the trans being cooled by the radiator

Having an electric fan or a mechanical fan I would pick electric only all day
having a mechanical AND and electric is better than just 1 or the other
but a mechanical fan alone will not pull enough air at slow engine speeds
and a crappy electric fan is only good for light cooling like a trans cooler
would need

Click to expand...

160 trans temp is not optimal anymore.Your trans temp gauge may or may not be reading the correct fluid temp depending on it's location.Heck your OEM temp gauge does not even read close to accurate,it give relative temp only.Newer engines and trans are made to operate and handle higher temps.Just a about 10-15 years ago 180 temps where considered normal,now 220 degrees is about normal.Better fluids help in this area.

Electric verses mechanical fan.............

Below 2500rpms the electric fan will always win and above 2500 rpms electric fans are not that far behind mechanical fans.The mechanical fan setup for a KJ is not meant to cool the engine b itself,only aid the electric fan under heavy loads as seen in towing.When I mud dragged raced(84 Blazer) by the end of the day I would be hitting 240-250 degrees on the temp guage with a new OEM fan and clutch(with full shroud) with a 42"x20" 5 row aluminum radiator,after ditching the mechanical fan for dual 10" puller fans(3800CFM each) and nothing else changed my temps never reached 160 degrees,had to block the radiator between runs to make the 160 degree t-stat open.


Running the trans fluid through a in-radiator cooler helps bring the fluid up to operating temp faster allowing better shifting,keeps the temp spikes controlled,and by the sending the fluid through a AUX cooler before returning to the trans will drop the temp more but not enough to effect shifting(cold shift lockout).In the colder months this setup becomes very good.