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Discussion Starter #1
I been suspecting that my trans temperature sensor has been off and thought that i had confirmed it by using one of those infra red temperature sensors. When i took the temperature of the oil pan, it was almost 65 degrees cooler than what my gauge read in the pod. However, i noticed that i left a few drops of trans oil in my driveway the other day and tracked it down to the back of the pan and it appears that it is coming from around one of the bolts (aftermarket pan).

That made me suspect the readings so I took the temperature of the sensor and the surrounding metal on the upper part of the pan. it was almost dead-on with what the gauge read.

Shouldn't the pan temperature be the same as the upper part where the sensor is and where the pan bolts to the trans? is it an indicator of a problem that there is a 65 degree difference?

Also, should i be worried about the drops of oil that I spotted coming from the rear of the pan?

I'm taking a road trip and i'm concerned that the temp at the sensor climbs to 200+ even though the pan is reading well below 170.
 

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Here's my thinking. The fluid travels through the trans, then to the cooler and back to the pan to be picked up and sent through again. If your sensor is in the pressure port, then your reading temps as it travels through the trans before the cooler.

I will wait for Mark to respond and tell me I passed or failed that class.

Obviously any leak isn't good, but if you check your fluid level often, you should be okay until it's more convenient to repair.
 

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You're right. The pressure port will usually be warmer than the pan. 65°F is a pretty large difference, I usually measured no more than a 25°F difference.
 

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Discussion Starter #4
thanks to you both. so the pressure port temperature is what I should go by?
 

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That's the one I use. FWIW, I have towed for hours @ 210 degrees. Mark suggested I use a good synthetic, and I would be okay all day long at that temp.
 

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I prefer reading the temperature either from the pressure port or using a gauge that reads the TFT sensor through the OBDII port.
 

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That's the one I use. FWIW, I have towed for hours @ 210 degrees. Mark suggested I use a good synthetic, and I would be okay all day long at that temp.

Another question here, how often should the fluid be replaced with mild towing???...I use Mobil1 syn.

~DR
 

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I suppose the regular service interval would be good. I changed my ATF when I bought the truck in '08, had 55,789 on the clock. Has 74,125 now. I just drained the pan, changed the filter for a look-see and added 6 qts of royal purple. Next service will include draining T/C and filling with Mobil 1. Probably do that at 85,000.
 

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Another question here, how often should the fluid be replaced with mild towing???...I use Mobil1 syn.

~DR
I still like 30,000 mile changes. I suppose you could run longer with synthetic, but I don't like to recommend doing that.
 
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