I have been using a temp gun to check my transmission pan temp. I get different readings when aimed at different parts of the pan.

My question is where is the right spot to aim? Directly on the bottom center? One of the indentations on the side? Bolt holes? The front portion that is vertical?

Any insight is appreciated Not my picture. Sourced from google

 

When I aim the temp gun at the front lower edge of the pan, I get a reading that is close to what the computer reports as the fluid temperature. It is best to do this right after a drive, with the engine still running.

 

Thanks was hoping you would see this

So front lower edge where it starts to curve from vertical to horizontal?

 

Yes, somewhere in that general area. I have found that location to be within a few degrees of what the probe and gauge I installed reads, and what the computer reports the sump fluid temperature to be.

 

Thanks I will try that spot tomorrow. I'm glad you have a gauge that your comparing it to. Its interesting that I will shoot the bottom of the pan and it will read way cooler than one of the indented spots along the side of the pan.

 

The non-contact thermometers use the emissivity of the part you are pointing it at. Higher end guns have the ability to choose different emissivities depending on the material. Also, color or finish such as matte or mirror can effect the reading. It is great if you can corroborate it with a known value, then always make sure you are looking at the same place.

 

The pan is all the same material/ color/ finish though isn't it?

 

That is correct. We don't want to overthink this.

 

Haha it was my job to overthink

 

if it's clean, not muddy, oily, partially painted, etc. there is also a product called thermochron. They are rugged buttons the size of large watch batteries. They are temperature data loggers. Basically connect them to a computer to start a data logging mission. Then remove from PC and tape them to the part you want to measure. Drive around for awhile and they will be continuously recording temperature data. Remove the thermochron and plug it into the PC to download the data. I used this exact method with a motorhome that had brakes that tended to overheat and get spongy. The thermochron is not very expensive. They are very rugged. You can use them in lots of applications.
http://thermochron.com/?gclid=CLnOi_...FdiKswodzkQKoA