How to install a Derale 20561 transmission cooler on your Wrangler TJ
- Thread starter Jerry Bransford
- Start date
I preparing for a 2-3 weeks long 2,000 mile road trip with lots of small back road trails at slow speeds. Should I install a Derale transmission cooler before I go? Jeep has 40,000 miles. Thanks and thanks to Jerry for the write up.
Another transmission cooler option is the direct fit Flexalite P/N 4116TJ , $104.77 on Amazon Prime as of 4/25/18. IMO, it is just as effective in most situations as the significantly more expensive Derale P/N 20561. Installation is easy.
https://www.amazon.com/dp/B018B6XDVC/?tag=wranglerorg-20
https://www.amazon.com/dp/B018B6XDVC/?tag=wranglerorg-20
I've heard of people using this one as well. My only issue with it is that it doesn't have a fan to help cool it.
A fan might be helpful for extremely slow four wheeling in low range, such as in extremely hot climates and when there is little or no air movement, but you would be surprised how much a simple auxiliary cooler will cool the ATF when mounted in front of a radiator with only the stock fan pulling air. It is more than enough for 95% of us - even in 4 low..
Just because someone touts a particular solution to a perceived issue doesn't make that solution the optimum for everyone in every situation. What might be "necessary" for desert rockcrawling or trailer towing might actually be a disadvantage in other environments.
Some potential advantages of the Flexalite cooler over the fan-based Derate cooler are lower cost, less complexity, no moving parts, and nothing between the frame rails to clog with mud. Sometimes simpler is better. The bottom line is that one should always carefully analyze one's particular needs and desires before blindly following anyone's recommendations for equipment modifications.
Just because someone touts a particular solution to a perceived issue doesn't make that solution the optimum for everyone in every situation. What might be "necessary" for desert rockcrawling or trailer towing might actually be a disadvantage in other environments.
Some potential advantages of the Flexalite cooler over the fan-based Derate cooler are lower cost, less complexity, no moving parts, and nothing between the frame rails to clog with mud. Sometimes simpler is better. The bottom line is that one should always carefully analyze one's particular needs and desires before blindly following anyone's recommendations for equipment modifications.
I use the Hayden 679 mounted in front of the radiator.
https://www.amazon.com/dp/B000C3BBKS/?tag=wranglerorg-20
https://www.amazon.com/dp/B000C3BBKS/?tag=wranglerorg-20
Speaking of transmission coolers, my Derale will be here on Friday, woohoo! Amazon had it for $288, which is a pretty good deal.
https://www.amazon.com/dp/B004XOO6C2/?tag=wranglerorg-20
https://www.amazon.com/dp/B004XOO6C2/?tag=wranglerorg-20
Yes, on the automatics, the lower portion of the radiator has the transmission fluid running through it.
Yes, in the bottom of the radiator. You can see where the lines to and from the automatic transmission attach in this photo:
The external ATF coolers we are talking about are all user add-ons.
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No wonder you need transmission coolers with that stupid design. I know there will people that disagree but *in general**, these systems can be bypassed without ill effects BUT maybe jeeps don't like to run on the cold side. I have bypassed that in every auto I have ever had and added a cooler and even towing a 12k trailer with my 600 rwhp cummins up steep grades my trans temps never got above 180 on the hot side. I have never had any side effects from doing this. Maybe it's not a good idea for some reason on the Jeep autos, not sure. Does anyone know?
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That’s interesting. I wonder if you could bypass the built in cooler and just run it straight into the Derale. Well, I’m sure you could, I just don’t know f you would lose any cooling effect from doing so.
The ATF cooling tube in the bottom of the radiator is a timed tested method that is as or more effective than a stacked plate or tube and fin external cooler (compare fluid to fluid heat exchange rates to fluid to air heat exchange rates.) It is still the primary method for cooling automobile ATF.
Unless the ATF cooling tube in the radiator is damaged or defective there is no reason to bypass it. In fact, bypassing the radiator and and re-routing ATF to an external cooler alone often results in less cooling, not more.
For a TJ an external cooler should be an add-on, not a substitute.
Unless the ATF cooling tube in the radiator is damaged or defective there is no reason to bypass it. In fact, bypassing the radiator and and re-routing ATF to an external cooler alone often results in less cooling, not more.
For a TJ an external cooler should be an add-on, not a substitute.
Ah gotcha, ignore my post then. Thanks for the info on the jeeps autos. While I disagree about the effectiveness of each cooling method, I see your points and like I said, I don't know jeep autos
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The fallacy with that argument is that the ATF cooling tube runs through the bottom of the radiator adjacent to where the already cooled coolant is returned to the engine. The temperature of the coolant in contact with the ATF cooling tube in a warm or even a hot engine is well within the normal operating range of ATF, never at 200 degrees.
Yeah I was just using that number as an example. But let's say it's 150 degrees, that still means that it is unnecessarily heating your transmission fluid up if the transmission was operating at 120 degrees. Like I said, some people will disagree with me and that's just fine, we all have our opinions and experiences and I have zero experience with jeep transmissions, just other experiences.
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The 120 degree example is based on incorrect assumptions. Automatic transmissions typically operate at 165-170 degrees.
You are right about it all because obviously that is important to you and anyone with differing experience is wrong which I'm fine with because I don't care about being right or wrong or what people do one way or the other as long as they are happy with their results.