transmission temp in reverse, fan needed? will it do much good?

[rweis]

Parking my 5er the transmission can get upwards of 225*. The check valve is out of the hot line. I know the prob is no air flow.



Has anyone mounted a electric fan to blow air through the transmission cooler when needed, ie stop and go traffic, backing the 5er, etc. If so how and how big a fan?



Bob Weis

 

[TTullio]

I put one on my older motorhome trans cooler. Actually, I had two trans coolers mounted in tandem. One was not enough. The fan was a sucker type (on back of cooler). It worked really well for times when the speeds are so low you're not getting airflow over the coolers; long, steep grades or stop and go traffic after freeway speeds when everthing was heat sinked. I would say it reduced transtemps probably 30 degrees or more. Tim

 

[juicedcummins]

I tried the small electrics a few years back and found them pretty much useless on a transmission cooler even with a t-stat.

If you wanted a better way to cool it down go to a Horton fan. The manual switch is ideal for situations like that. They are pricey though.

 

[rweis]

I tried to get a Horton for a 2002 and they did not make them for 2002. Something about Dodge changed the wiring harness and DC and Horton had a falling out.



I think the last year Horton made for DC was 2000.



Anyone have any ideas here?



Might work if I knew the wiring differences between the last year Horton made for DC and the 2002. I do not want to take a hunch at the Horton price level.



Bob Weis

 

[TTullio]

You may just want to put a second trans cooler on, this is what I did with the motorhome and it worked very well. I started off installing a full compliment of real gauges for water, oil and trans temps. SHOCK! The grade out of Salt Lake City drove the trans temp to 280 degrees! This was a very slow pull with very little air going over the cooler. That's when I went with a second trans cooler and a fan over them and the oil cooler. Now, even in 100 degree air temps pulling a trailer up long steep grades the trans temp would never go over 200 degrees. Tim

 

[rweis]

I tried to get an H7B (1/2" tubing, full flow) out of a place in AZ on the EBay and got taken royaly, I paid, they never sent it. I got the fan from a seperate supplier and so do have the fan. Probably a second cooler and fan is the smartest thing. Do it right ONCE!



So far I have only gotten the transmission temps to 240 for about 20 seconds backing one time, but can see ramifications if I had to back up an incline.



I need to find a good place for the cooler & fan combination out of the way with good air space and not hot. I think that leaves out the passenger side with the exhaust pipe / muffler / exhaust brake over there. I put the RACOR in the pocket at the front of the bed underneath. Need to hunt up another place I think.



Thanks,



Bob Weis

 

[rweis]

OK, have decided to add a transmission cooler, now where in the system?



The transmission system is out of the transmission with the hot line, into the water heat exchanger. out of the water heat exchanger, over to the transmission air cooler, then back to the transmission pan.



I have the '96 hot line with temp probr port and the flexable hose from the transmission hot line to the water heat exchanger. Both ends are AN-8's and would be easy to get into the fluid line there and would be on the same side of the vehicle as where I am planning the aux cooler and fan.



However it is before the water heat exchanger. Would the water heat exchanger just heat the transmission fluid back up?



I could get into it as the fluid line goes back into the pan, divert it there and run it to a aux cooler with fan, then back to the transmission dump into the pan.



The easiest would be the flex into the water heat exchanger, but that may not be a good place to get into the system.



I plan to mount the aux cooler and fan back in the pocket under the bed on the drivers side.



Ideas?



Bob Weis

 

[Midnight]

That is exactly where one of my neibours installed his second cooler with aux fan. He said that it did help. Me on the other hand, installed a fan on the trans cooler with a switch so i could run it when needed. I can't say that it helped all that much.