Where to bolt oil temp sensor?

[matuva]

Good day all;

anybody has any suggestion or recommendation for where to install the temp sensor of a trans oil temp gauge on a 4L80E?

Would I have to drill the pan and weld a nut, or is there any available port I miss?

 

[bison]

I think low in the front of the pan is the best spot ,that way way the sensor is in the oil reservoir(and can double as a drain plug) and the wire can be routed so it wont get damaged from road splatter or other things.
Grind the coating of the pan were you plan to place the bung otherwise you gonna have a sloppy weld that might leak.(don't ask how I know )

 

[WarWagon]

Most 4l80e's have a port on the driver's side about the middle just above the pan. It has a plug you remove and your temp sensor can thread into.

 

[billyg38120]

It all is dependant on your temp sensor. When I need to verify the TCM trans temp I use a K-Type Thermocouple wire twisted and use the dipstick tube and connect it to a Fluke 52 meter. It WILL read a bit different for a short period of time WHILE Driving. This is due to the return oil into the sump difference. I've seen 5 to 10 deg F for a minute of two.

If I had to install an electrical sender I would TIG weld a drain plug AND the female part of the sender in the rear of the pan and make it enter in the rear so NOT to extend below the pan. It works really well. (My Drag Race THM400 had a thermocouple in the rear beside the drain plug.)

(I use the K-Type thermocouple wire twisted together on the red/yellow wires on the test end instead of a t-couple for 75 bucks. The wire fits dwon the dipstick and can be EASLY twisted down the dipstick itself and placed through the small hole in the end of the dipstick to hold it in place. If you look at the other end of the dipstick, most NON-locking have a vent cut out for the thin t-couple wires to pass through. If it's a locking stick I just lock it with the wires through. I've used this for years.

I don't use the pressure port for temp sense. I hope this will help someone.

 

[hookedup50]

I used the War Wagon method. The port is in a blind spot, but with a light and mirror its a pretty simple install.

 

[billyg38120]

If you elect to use the 1/8 inch pipe plug for your Trans Temp Sensor, just keep in mind the Port is actually used for testing the trans PRESSURE and can exceed over 250 psi. I would suggest using the Pan and have a pipe thread female nut TIG welded into it for the Temp Sensor. (If you are in the Salt belt be sure to paint or coat the weld on the outside. I would place the sensor in the rear of the pan and face to rearward so it won't not hang down.

 

[WarWagon]

Not had any issues with the pressure on the temp sensor in the port. As hard as I run mine I suggest this location is bullet proof. The probe has outlived 3 transmission rebuilds.