New OBD2 gauge installed - Aeroforce Interceptor
08-06-2008, 05:29 PM
#11
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08-06-2008, 05:45 PM
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08-06-2008, 05:51 PM
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Where is the tranny temp sensor located on the automatics? I'm just wondering where the ecu gets its temp reading from , which would affect how accurate the gauge is. This thing definately looks interesting though.
08-07-2008, 07:27 AM
#15
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The transmission temperature sensor (2) is located in the transmission range sensor (1) and communicates transmission sump temperature to the TCM.
and The Transmission Range Sensor (TRS) (2) is mounted to the top of the valve body inside the transmission and can only be serviced by removing the valve body assembly. The electrical connector extends through the transmission case.
So the answer is...the sensor lies somewhere deep in the bowels of the transmission. I've heard varying opinions on the "best" place to measure transmission temperature - some say it's on the way out to the cooler (since that's where the temp will be at its highest); some say on the way back from the cooler (since that's the temp of the fluid after it's been cooled and before it flows back into the transmission); others say in the pan (since that is as close as you can get to the transmission internals). I would say deep inside the transmission is about as good as you can get, since that's where the fluid is making contact with the internal parts and doing its thing. What it doesn't tell you is the maximum temperature your fluid is reaching, and I think that's what you're getting at. It would be nice to know how hot your fluid gets at its hottest point, because that would give you an idea on the longevity of your fluid.FYI, I get readings around 150-170 in stop-and-go traffic, and 120 on the highway. I have a B&M transmission cooler installed in front of my radiator. I will be towing my trailer (3000 lbs) in the mountains next weekend, which is the main reason I wanted to be able to watch transmission temperature. I'll let you know what kind of readings I get on that trip.
Last edited by undertow119; 08-07-2008 at 08:07 AM.
08-07-2008, 03:09 PM
#16
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The factory transmission temperature sensor is mounted in the valve body because it is included in the range selector sensor. The temp probe sticks down into the sump fluid.
Short term temp spikes as would be seen in the torque converter are normal and do not degrade the fluid. It is the long term rise in average temp in the sump which will degrade the fluid. High temp in the sump means the fluid is getting hotter than the cooler can handle. It's like the engine temperature. There are very hot areas in the head, but the water temp (and oil temp for some) is the index of engine health.
Short term temp spikes as would be seen in the torque converter are normal and do not degrade the fluid. It is the long term rise in average temp in the sump which will degrade the fluid. High temp in the sump means the fluid is getting hotter than the cooler can handle. It's like the engine temperature. There are very hot areas in the head, but the water temp (and oil temp for some) is the index of engine health.
