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Aux. Trans underbed cooler

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What is I-70 like?

Where and how have you guys mounted an underbed fan forced trans cooler? Have you plumbed it as the 1st cooler on the trans out line to reduce the heat load going into the stock system? Any pictures of the mounts? Any experiences as to stacked plate vs. tube & fin coolers, or does the relative difference really not matter that much? How large a unit and has it reduced the trans temp significantly when unlocked and backing? Thanks.
 
Talk to the people who sold it to you

Scott at Massdiesel is a good people to talk to for help. Do you have a ranny temp gauge?You must pull very heavt loads to need a cooler with a fan. I had a class A motor home that had the fans on the coolers but the reason was the radiator was to small. I later installed a larger radiator and the problem was sloved. I also installed a transmission temp gauge and without one you are just don't know anything what going on.
 
I put a H7B and a fan in the passenger side bed pocket. Whenever I tow I run the fan. Especially useful when backing, I never let the transmission fluid (hot line) get over about 210* or so. Whith the aux cooler it has never gotten over 200* not backing.



I used the H7B because BK on the DTT web site recommended it. It is a stacked plate cooler.



My circuit is transmission, hotline with sensor fitting, normal tubing up to the male fitting that goes to the water heat exchanger. Then back to the H7B cooler, then forward to the water heat exchanger, and on to the front transmission cooler and back to the transmission.



I temp sample the pan as well as the hot line.



Bob Weis
 
To add a question to this, who sells the little kit to put a transmission temperature sensor into the hot line?



thx
 
I added a cooler on my 93 under the bed as you descibed. it was fan forced and frankly, rather spendy. Didn't make any noticeable difference on the trans temp gage. Boy was I dissapointed.
 
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Mine is mounted on the left side just behind the transmission, inside the frame using 11/2" angle iron welded to the frame. 3/16" I believe. Forgot the brand name, but is plumbed in the return line and then to transmission. My recollection is that DTT said not to put anything in the cooler line, so. It works very well. I have it on a switch, so when the traffic stops the cooler goes on, and keeps it cool. Temps never increase.
 
I think BK recommended the H7B because of the flow (1/2 npt) and it would not be a restriction. He said DO NOT take out the water heat exchanger! I do not remember anything on the DTT site about not putting it in the hot line going to the water heat exchanger, but I will do a DTT site check and call DTT if I can not find anything.



Bob Weis
 
rweis said:
I think BK recommended the H7B because of the flow (1/2 npt) and it would not be a restriction. He said DO NOT take out the water heat exchanger! I do not remember anything on the DTT site about not putting it in the hot line going to the water heat exchanger, but I will do a DTT site check and call DTT if I can not find anything.



Bob Weis



I do not think the thread in mind concerned a cooler, but a filter. From my understanding it should be in the return line, since the fluid initially needs to be warmed. So as to not interfer with the factory system, I put it in the return line. The problem, with the 2nd gen atleast, is the fact that the factory cooler is not infront of the fan and does not cool when sitting still or at low speeds. It would help if it was moved to the center of the radiator.
 
i am also in the market for an auxiliary cooler with fan. i hate having to shift into neutral at extended traffic lights. but that is a small price to pay for such a tight converter.


mark
 
There are several places that sell the kit to install

I got the gauge from Massdiesel ask for Scott. I think he the brains of the outfit there. He will help you.
 
Prairie Dog said:
I added a cooler on my 93 under the bed as you descibed. it was fan forced and frankly, rather spendy. Didn't make any noticeable difference on the trans temp gage. Boy was I dissapointed.



Go down to Arizona in the summer. :)



DBF
 
guava said:
To add a question to this, who sells the little kit to put a transmission temperature sensor into the hot line?



thx



I used an ISSPRO R9055 gage and an ISSPRO R8961 sender.



http://www.isspro.com/



Using two wrenches so you don't snap something, remove the transmission cooling line output at the transmission (hard to get to, but it makes installing the sender much easier). The line will drop down so you can put a vise-grips on the boss and remove the switch in the output line. (This switch disables overdrive if output temp goes over 275*).



Put in the sender (3/8" NPT) using teflon tape or liquid and tighten it against the vise-grip. Re-install the output line into the transmission. Tiewrap the switch to something to keep it from banging around in the breeze.



Run the electrical leads as you want. Make sure you get a good ground connection to the engine or transmission; body ground can have some resistance back to the engine which would make the gage inaccurate.



Some folks like to put in a tee at the output line so they can plug in both the original switch and the new sender. Your choice.



DBF
 
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TFlewitt said:
Where and how have you guys mounted an underbed fan forced trans cooler? Have you plumbed it as the 1st cooler on the trans out line to reduce the heat load going into the stock system? Thanks.





The Dodge under-the-bed cooler was plumbed to be the first thing in the output line from the transmission.



After that, it went to the heat exchanger (auto trans only) on the passenger side of the block under the turbo, then to the little cooler above the radiator.



Then back to the trans input.



It was located behind the driver between the bed's outer skin and the frame. It mounts to a plate that then is attached to two body support rails by well-nuts into holes drilled in the rails. See my pictures for some detail.



DBF
 
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