Trans temp question

[josh93rodeo]

I added a B&M trans temp gauge with the sending unit mounted in the pressure port on the A4LD in my 91'. With everyday driving around town and freeway driving the temp never gets much over the 100* mark (I'm guessing somewhere around 120-130). It's hard to tell exactly because the gauge has a 100* mark and the next mark is 160 and it's in between the two. Is this a normal temp range for the A4LD?

I'm just wondering if I'm getting a reliable reading from the pressure port.

 

[Tbars4]

...This may help....

http://www.explorerforum.com/forums/showthread.php?t=225103

 

[2000StreetRod]

Trans temp

I just completed my installation with two external transmission oil coolers for my 5R55E. http://www.explorerforum.com/forums/showthread.php?t=247990 I use the radiator oil cooler to "warm" the engine oil instead of the transmission oil. On my first 5 mile trip the transmission oil reading never reached the minimum mark of 100 degrees but the engine oil reading reached 155 degrees and was still increasing. I think it is a mistake to route transmission oil thru the radiator "cooler" that is maintained at 190 degrees by the thermostat.

 

[coppe]

I just completed my installation with two external transmission oil coolers for my 5R55E. http://www.explorerforum.com/forums/showthread.php?t=247990 I use the radiator oil cooler to "warm" the engine oil instead of the transmission oil. On my first 5 mile trip the transmission oil reading never reached the minimum mark of 100 degrees but the engine oil reading reached 155 degrees and was still increasing. I think it is a mistake to route transmission oil thru the radiator "cooler" that is maintained at 190 degrees by the thermostat.

i saw your whole write up, and it was a great install, but the thermostar will maintain that temp in the coolant inside the block, while the coolant outside it (for example the radiator) is always way cooler when the thermostat is closed, and a bit less cool when the whole system is recirculating, or at least that is what i´ve always believed, i might be wrong, and i wouldnt be able to do an adaptation as yours. or maybe you´ve got more gauges and sending units and stuff that made you realize that.

 

[2000StreetRod]

Valid point!

. . . the thermostat will maintain that temp in the coolant inside the block, while the coolant outside it (for example the radiator) is always way cooler when the thermostat is closed, and a bit less cool when the whole system is recirculating, or at least that is what i´ve always believed, i might be wrong, and i wouldnt be able to do an adaptation as yours. or maybe you´ve got more gauges and sending units and stuff that made you realize that.

You have a valid point and that's probably what Ford engineering was thinking when they planned the stock configuration. Since I replaced my stock single row radiator with a double row, my coolant temperature is always a steady Normal after warmup as shown on the instrument cluster gauge. I have validated the reading with my laptop based scanner (Dyno-Scan). In my opinion, to extend transmission life it is more important to decrease the maximum temperature than it is to increase the minimum temperature. And even more so for synthetic blends (Mercon V) and full synthetics that can better tolerate cool temperatures. Also, in theory, my 5R55E transmission is supposed to have internal thermostatic control to maintain the ATF optimum temperature range. I have yet to confirm the capability. On a hot day with an engine under load the engine coolant thermostat (190 deg) will be constantly full open trying to keep the engine coolant temperature below 200 degrees. If the heat generated by the engine exceeds the radiator cooling capacity the coolant temperature will increase. I don't know to what extreme, but I suspect greater than 212 degrees (the reason pressure caps were incorporated). By the way, the optimum engine oil temperature is 190 to 200 degrees. I would have preferred to have thermostatically controlled engine oil but the ease of having a remote filter and a bypass filter was a higher priority for me. I may add thermostatic control in the future.

 

[Tbars4]

....Just a quick note on the link I posted....:scratch:

...My setup does not run thru the radiator and has a single seperate cooler in front of the radiator....The A4ld is a different beast and does normally see higher temps than most other transmissions...

...Can you post a pic of your B&M temp guage and another pic of how you tapped into the pressure port???...I am guessing your guage is mechanical and not electronic...

 

[josh93rodeo]

This is a pic of the gauge I'm using, it's an electric gauge.

This is the pressure test port I stuck the sending unit in. It's the bolt just to the right of the shifter and it's 1/8 NPT, perfect for my sending unit. I read about mounting it in this location from another thread on this site.

 

[Tbars4]

...Thanks for the second pic as I could never get one of exactly where that test port sat...:biggthump

...I have read of putting a pressure gauge there as I will be doing in the future, but I don't recall a thread using that on an A4LD for temp reading...

...I did choose my mechanical gauge for it having a better definition in degree's and also the ability to watch it cool down, even when the vehicle is off...

 

[josh93rodeo]

I found some of the info about the temp sending unit in the pressure test port. Brooklynbay is the one that suggested putting it there. Maniak then said that the reading you would get from the pressure port would be about the highest temp reading you could get.


Quote:
Originally Posted by BrooklynBay
One place to put it without having to fabricate anything fancy would be to remove the pressure port plug on the driver's side of the transmission, and screw it in there. Some people say that the pan is the best spot since it has the most amount of fluid in one area which is constantly circulating. Some people add a remote filter, but claim that it's not accurate enough. Keep in mind that it has to be on the line before it goes to the cooler.

Maniak posted this response:

Just remember that where you put it determines what your readings are. The port mentioned above is about as warm as the fluid will get since you are reading it right about where the converter is done with it. (other than the cooler line coming out of the trans)..

If you read it from the Pan you will read the temp of the fluid that most of the transmission is seeing.

Just remember that you want to see your trucks "normal" temp and then keep an eye on it to see when something isn't right.

~Mark

From this thread:

http://explorerforum.com/forums/showthread.php?t=162567&highlight=pressure+port+temp+gauge&page=2


I'm just wondering if it's normal that I'm getting such low temps from this location with normal daily driving. I should note that I've seen some pretty high temps while off road and climbing steep grades (around 230* max).

 

[rhauf]

The trans temp in my '93 explorer hangs around 120 or so if the torque converter is mostly locked, but when i'm doing mountain driving or other "non locked" driving, it gets up close to 200. i think anything below 200 is a good temp.

now the trans temp on my bronco however... (with a 2500rpm stall) gets a little warmer (trans temp gauge on right)

 

[Tbars4]

...From both of those quotes, I would put it in the pan....

..If you notice on the link I posted, there are temp readings in the first post and they also include the outside ambient air temp at the time of each drive...

..The reason I mention this is you note your tranny temp but I am guessing your outside ambient air is around 60-70*???....For how long are you driving to get your temp reading and is this on the highway, flat road, or stop and go traffic???

...As you drive your tranny will accumulate heat and raise the temp so there are a lot of factor's in a temp reading to think about...One thing for sure, each time over 210-220* and it is time to change your fluid as it starts loosing it's properties with heat..

 

[josh93rodeo]

Sorry, I should have posted more info.
My drive to work is about 25 miles each way, almost 100% freeway driving at 65-70 MPH.
Outside temps have been around 60*-70*.
When I have driven around town with stop and go it wasn't for more than 15-20 minutes with outside temps around 90* and the trans temp was about the same at 130* or so.

 

[Tbars4]

...Then your temp readings sound just fine...

...I have actually driven about that distance w/ 60-70* temps outside, jumped directly on the freeway, and not even got my temp gauge to read until I got off the freeway...

 

[josh93rodeo]

Thank you, that's good to know

 

[coppe]

You have a valid point and that's probably what Ford engineering was thinking when they planned the stock configuration. Since I replaced my stock single row radiator with a double row, my coolant temperature is always a steady Normal after warmup as shown on the instrument cluster gauge. I have validated the reading with my laptop based scanner (Dyno-Scan). In my opinion, to extend transmission life it is more important to decrease the maximum temperature than it is to increase the minimum temperature. And even more so for synthetic blends (Mercon V) and full synthetics that can better tolerate cool temperatures. Also, in theory, my 5R55E transmission is supposed to have internal thermostatic control to maintain the ATF optimum temperature range. I have yet to confirm the capability. On a hot day with an engine under load the engine coolant thermostat (190 deg) will be constantly full open trying to keep the engine coolant temperature below 200 degrees. If the heat generated by the engine exceeds the radiator cooling capacity the coolant temperature will increase. I don't know to what extreme, but I suspect greater than 212 degrees (the reason pressure caps were incorporated). By the way, the optimum engine oil temperature is 190 to 200 degrees. I would have preferred to have thermostatically controlled engine oil but the ease of having a remote filter and a bypass filter was a higher priority for me. I may add thermostatic control in the future.

men i think i´m gonna be checking my trans tag, to see if it has thermostatic control, and the temp specs and stuff, it´s always good to learn something.