Transmisssion temp sensor location
#2
JK Jedi Master
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The plugged ports on the side of the transmission are for pressure tests. No fluid passes through them.
Below is probably more than you asked for, but other readers may find it interesting, too.
This is what my research has revealed about trans temp probes located in the various points on the 42RLE transmission.
The following is what I have concluded based on my best effort to get the facts.
Line out to the cooler:
This will show temperature of fluid coming out of the trans, but it will be variable with short term spikes as the TC locks and unlocks. Short term temp spikes are normal and not detrimental to transmission fluid life. A probe in this location can lead to unnecessary anxiety.
Line from cooler to transmission:
This will show the fluid after cooling, and will be lower than what the pump picks up from the pan.
In one of the many pressure ports on the side of the transmission:
These ports are for connecting a pressure gauge for testing purposes. They are torque converter clutch on, torque converter clutch off, reverse, low/reverse, 2/4, underdrive, overdrive.
Fluid doesn't pass through them, so a temp reading wouldn't show true fluid temp.
This brings us to the pan:
This will show temp of fluid the pump picks up and sends through the transmission. The sump is sort of a "dampener" for fluid temperatures. It reflects the steady state temperature of the fluid. Long term temp rise, which is what degrades the transmission and fluid, will show in the sump. As mentioned above, short spikes in temp as the fluid leaves the transmission are not a factor.
The transmission's factory temp sensor monitors the fluid in the sump. The normal programs in the tranny controller respond to sump fluid temperatures.
The troubleshooting charts and operational limits are based on sump temps.
Some brands of transmission temp gauges recommend an inline probe location IF installing it in the pan is not possible for some reason.
Several local transmission shops recommend the pan location. However, they say most people choose one of the inline locations for ease of installation.
I installed a sensor in the pan. Since then, I bought an AeroForce Interceptor gauge that reads sump temperature through the OBD II connector.
Below is probably more than you asked for, but other readers may find it interesting, too.
This is what my research has revealed about trans temp probes located in the various points on the 42RLE transmission.
The following is what I have concluded based on my best effort to get the facts.
Line out to the cooler:
This will show temperature of fluid coming out of the trans, but it will be variable with short term spikes as the TC locks and unlocks. Short term temp spikes are normal and not detrimental to transmission fluid life. A probe in this location can lead to unnecessary anxiety.
Line from cooler to transmission:
This will show the fluid after cooling, and will be lower than what the pump picks up from the pan.
In one of the many pressure ports on the side of the transmission:
These ports are for connecting a pressure gauge for testing purposes. They are torque converter clutch on, torque converter clutch off, reverse, low/reverse, 2/4, underdrive, overdrive.
Fluid doesn't pass through them, so a temp reading wouldn't show true fluid temp.
This brings us to the pan:
This will show temp of fluid the pump picks up and sends through the transmission. The sump is sort of a "dampener" for fluid temperatures. It reflects the steady state temperature of the fluid. Long term temp rise, which is what degrades the transmission and fluid, will show in the sump. As mentioned above, short spikes in temp as the fluid leaves the transmission are not a factor.
The transmission's factory temp sensor monitors the fluid in the sump. The normal programs in the tranny controller respond to sump fluid temperatures.
The troubleshooting charts and operational limits are based on sump temps.
Some brands of transmission temp gauges recommend an inline probe location IF installing it in the pan is not possible for some reason.
Several local transmission shops recommend the pan location. However, they say most people choose one of the inline locations for ease of installation.
I installed a sensor in the pan. Since then, I bought an AeroForce Interceptor gauge that reads sump temperature through the OBD II connector.
#3
JK Enthusiast
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Join Date: Dec 2011
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The plugged ports on the side of the transmission are for pressure tests. No fluid passes through them.
Below is probably more than you asked for, but other readers may find it interesting, too.
This is what my research has revealed about trans temp probes located in the various points on the 42RLE transmission.
The following is what I have concluded based on my best effort to get the facts.
Line out to the cooler:
This will show temperature of fluid coming out of the trans, but it will be variable with short term spikes as the TC locks and unlocks. Short term temp spikes are normal and not detrimental to transmission fluid life. A probe in this location can lead to unnecessary anxiety.
Line from cooler to transmission:
This will show the fluid after cooling, and will be lower than what the pump picks up from the pan.
In one of the many pressure ports on the side of the transmission:
These ports are for connecting a pressure gauge for testing purposes. They are torque converter clutch on, torque converter clutch off, reverse, low/reverse, 2/4, underdrive, overdrive.
Fluid doesn't pass through them, so a temp reading wouldn't show true fluid temp.
This brings us to the pan:
This will show temp of fluid the pump picks up and sends through the transmission. The sump is sort of a "dampener" for fluid temperatures. It reflects the steady state temperature of the fluid. Long term temp rise, which is what degrades the transmission and fluid, will show in the sump. As mentioned above, short spikes in temp as the fluid leaves the transmission are not a factor.
The transmission's factory temp sensor monitors the fluid in the sump. The normal programs in the tranny controller respond to sump fluid temperatures.
The troubleshooting charts and operational limits are based on sump temps.
Some brands of transmission temp gauges recommend an inline probe location IF installing it in the pan is not possible for some reason.
Several local transmission shops recommend the pan location. However, they say most people choose one of the inline locations for ease of installation.
I installed a sensor in the pan. Since then, I bought an AeroForce Interceptor gauge that reads sump temperature through the OBD II connector.
Below is probably more than you asked for, but other readers may find it interesting, too.
This is what my research has revealed about trans temp probes located in the various points on the 42RLE transmission.
The following is what I have concluded based on my best effort to get the facts.
Line out to the cooler:
This will show temperature of fluid coming out of the trans, but it will be variable with short term spikes as the TC locks and unlocks. Short term temp spikes are normal and not detrimental to transmission fluid life. A probe in this location can lead to unnecessary anxiety.
Line from cooler to transmission:
This will show the fluid after cooling, and will be lower than what the pump picks up from the pan.
In one of the many pressure ports on the side of the transmission:
These ports are for connecting a pressure gauge for testing purposes. They are torque converter clutch on, torque converter clutch off, reverse, low/reverse, 2/4, underdrive, overdrive.
Fluid doesn't pass through them, so a temp reading wouldn't show true fluid temp.
This brings us to the pan:
This will show temp of fluid the pump picks up and sends through the transmission. The sump is sort of a "dampener" for fluid temperatures. It reflects the steady state temperature of the fluid. Long term temp rise, which is what degrades the transmission and fluid, will show in the sump. As mentioned above, short spikes in temp as the fluid leaves the transmission are not a factor.
The transmission's factory temp sensor monitors the fluid in the sump. The normal programs in the tranny controller respond to sump fluid temperatures.
The troubleshooting charts and operational limits are based on sump temps.
Some brands of transmission temp gauges recommend an inline probe location IF installing it in the pan is not possible for some reason.
Several local transmission shops recommend the pan location. However, they say most people choose one of the inline locations for ease of installation.
I installed a sensor in the pan. Since then, I bought an AeroForce Interceptor gauge that reads sump temperature through the OBD II connector.
#4
JK Jedi Master
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I have seen T's installed into the cooler line for a sensor.
I have also seen the sensor taped to the line, and covered with insulation.
If you do your own transmission fluid/filter change, you can easily install a probe in the pan.
I have pictures of that if you want to see them.
#5
JK Freak
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Before you try splicing into the sensor see if the torque app and a 15 dollar odb2 sensor works to read the stock sensor. That is what I do and I have a post on this forum on how to configure it. Give my name a search with the torque keyword.