Engine/Transmission (1998.5 - 2002) Trans Coolent Line # 05011244AA

[WTBurke]

I'm doing a full A-pillar for my Hewitt Gauges. The Transmission Temperature Gauge as per Bill K. at DTT has directed me to the correct point in the fluid flow chain to place the temperature sensor. The optional line available from Dodge is part number #05011244AA. It has a special housing to allow easy placement of the sensor.



I'm preparing this new "coolant line" for installation and I must remove the black powder coating from the fitting that attaches to the output fitting of the transmission. You would do this for proper DC ground of the line to chassis/transmission integrity. In simple terms the gauge has a single wire lead running to the temperature sensor and the DC ground return path is the body of the sensor mounted into it's metal cavity nest.



Here is the my QUESTION... . what is this rubber extension piece w/fittings on the end that attaches to the engine coolant heat exchanger? It has a spring loaded check ball in it!



I have not removed the original factory coolant line at this time however, in viewing it as it attaches to the heat exchanger it is a full hard line with fittings on each respective end and there appears to be no such apparatus on the OE line.



I can't blow through this thing with human power but, my compressed shop air will blow the ball off the seat in the "one-way-direction"... . the restriction is quite high and with air it makes the flibbering-pharting noise of a rubber check ball playing on the seat.



This optional coolant line has been on the DTT web site for a long time and I've never seen anyone speak about this oddity? It was expensive too !!!



I understand "check-valves" in a one-way-flow system but, this baby sure has some restriction to it and it's causing me to question what's up with this?



I have no doubt this line is the way to go in regard to reading absolute temperature of the transmission at the most critical point. The design of the assembly is outstanding for just this reason... . but... what is the "potato in the exhaust pipe" all about?



William

 

[rotohead]

I've had that same line in my truck for over seven yrs and has worked great. I'm not sure but I think the check ball is to prevent the TC from draining out when the truck sits.
Chuck

 

[CSnyder]

Chuck is 100% correct!

 

[WTBurke]

Double Check Valves

I thought I'd bring this back to the top as I found additional information about this transmission fluid line.



It appears that the "heat exchanger" on the right side of the CTD has a "check valve" on the input line side. This optional line from Dodge comes with the rubber extension fitting that incorporates (see photo above) an in-line check valve too!



I call DTT and spoke with Darrin and he informed me that when you remove the original line from the heat exchanger "if" the fluid doesn't drain back into your face then there "is" already a check valve within the heat exchanger its self. (makes sense to me)...



Hence, I had two check-valves in series.



Darrin informed me that DTT has an optional steel braided hose assembly that removes this additional check-valve arraignment on CTD's that have the check valve within the heat exchanger. So... . I'm assuming some CTD 2nd Gen rigs have this assembly and some do not.



So... I went to my local hydraulic shop and had a very nice line and fitting assembly prepared and I have removed that original assembly and placed this straight-through line and fittings in place.



Darrin eluded to the fact that two check-valves in series could very well lead to fluid flow restrictions and possible additional heating of the transmission fluid due to restricted flow.



This optional part #05011244AA transmission fluid line does not come with any instructions to alert a DIY guy to these observations. So... . I guess double checking is good so as to "not" double check your fluid flow.



William