Test port question

[Dave98XLT]

Is this the pressure test port where I can put in put in a atf fluid temp sensor?

it looks like pipe thread plug with a nut over it on drivers side of 5r55e transmission. there are two of them.


(i have a picture but can't upload attachments, sorry)

 

[Gadget X]

Best place for a temp sensor would probably be in the pan, where it would be submerged in fluid, I would think. Not familiar with the 5r55e, though.

 

[Dave98XLT]

Thanks for the help and someday I plan to go that route. For now I just wanted to do something temporary and I read on the forum there is a pressure test port on some of the transmissions can be used for this. Question is whether these bolts are test plugs or something else? And if so is this before or after the coolers as far as whether the fluid is close to the hottest point?

 

[JK080]

Thanks for the help and someday I plan to go that route. For now I just wanted to do something temporary and I read on the forum there is a pressure test port on some of the transmissions can be used for this. Question is whether these bolts are test plugs or something else? And if so is this before or after the coolers as far as whether the fluid is close to the hottest point?

It sounds like you are describing the band adjustment bolts, don't remove those. Use the line pressure tap location shown in the picture.

 

[Dave98XLT]

Yes I see it now. Any idea what thread it is, SAE or metric? What temp range should I expect to see there, and what would be the sensible limit while towing?

Thanks much

 

[sypher9]

Hello. I'm not sure how accurate it is but I use the torque app on my phone to monitor my transmission temps in my Ranger. You just need an obdII bluetooth connector to hook it up. Just in case you wanted a different option.

 

[arco777]

Is this the pressure test port where I can put in put in a atf fluid temp sensor?

it looks like pipe thread plug with a nut over it on drivers side of 5r55e transmission. there are two of them.


(i have a picture but can't upload attachments, sorry)

I've been over this question with the E4OD in my Bronco and spent hours reading and researching. The short answer is that yes you can install a temp gauge sensor in a trans test port. However, generally these ports do not get fluid flowing over them - they just sit in fluid that's at a dead end. As such you end up measuring case temperature more than fluid temperature. Convection only goes so far. It's enough to make most people happy, and the gauge needle will move as the trans warms up, but it's not accurate. You want to install a temp sensor in the pan, in my opinion.

While you could sample temperatures at several different locations - pan, lines pre-cooler, lines post-cooler, integrated valve body or solenoid pack sensors - I believe the best spot is the pan. Ideally about halfway up the side, though you can use the bottom to have your sensor double as a drain plug if desired (just add a few degrees for heat rise and underbody pan cooling).

It's true you can tap into factory installed sensors for readings. I don't feel this is the most accurate method though; factory sensors aren't required to be extremely accurate, since the PCM cares more about "Change to Shift Schedule B if sensor exceeds 200 degrees" type stuff rather than knowing precisely how far below 200 you are. It doesn't need to know exact temperatures, just ballpark. Some sensors can be accurate, others can be a simple heat switch.