Tranmission Temperature Probe in Outlet Line?

[MMathewson]

After reading many posts about where to put the 48re transmission temperature probe, I have decided to put it into the line between the transmission output and the water/oil cooler (on the rear of the engine). I haven't been able to find a manifold to use since the lines measure 0. 50 inches O. D. and the Autometer manifolds are for 5/16th and 3/8th.



Thus my plan is to remove the pipe between the transmission outlet and water/oil cooler input, then cut it and put in a brass compression TEE in it. I wasn't planning to flare the ends, but simply use the sleeve compression. Then re-install the pipe and put in my probe in the TEE.



Has anyone else put their probe in this location? Are there any gotchas that I need to know about? How much transmission fluid will I lose when I disconnect the pipe and is it worth replacing?



Thanks

 

[Kennywould]

I would not use compression fitings on a transmission line, someone makes a line just for the purpose of installing the sender, I was looking for one myself, I have mine installed in the rear test port and it doesn't seem to work well there. I think your asking for trouble with compression fittings because of the vibration, scares me! I had a recall on mine for possible line failure under towing loads, the lines were prone to crack.



-Ken

 

[Kennywould]

- MM

That recall was on my 04'



-Ken

 

[BIG BOB]

Get ahold of Scott and Mass Diesel! He make a replacement tranmission line that goes from the hot side of the transmission to the cooler. This line has a bung for the temperature probe built right into the line.



Mass Diesel!

 

[Kirwin]

transmission line replacement

I did this with the Mass Diesel replacement line on FSchmidt's truck. See post under title Auto Transmission Temperatures in the 3rd gen forum. I lost about 2 quarts of transmission fluid. It will continuously drain (but not rapidly) from the line fitting on the transmission while you have the tube out. I put some tin foil under the fitting on the transmission as I wanted to minimize the mess that I had to clean up. The other end of the line is directly over the starter so I covered the starter with tin foil too but not much came out of that side. I guess the water to oil cooler drained back through the return line. I had his truck up on ramps as its a 2WD and I'm too fat to slide under it on the ground. This may have affected how the fluid drained. The Mass Diesel part was well made with flared ends on the stock tubing with a AN nitrous fitting with a 1/8" side tapped hole for the sender to mount in. I loosened the fitting up to allow me to turn the sending unit to provide max clearance from the surrounding componets as I know that things do move around when you apply 600 lb-ft of torque.

 

[Red360]

Trans Line

DTT also carries this line... great product!!!

 

[MMathewson]

I bought the Mass Diesel part and installed it. I found out I also had to ground the transmission sensor since the tubing was not electrically grounded after I installed it. I have yet to see any temperatures even approaching 100 degrees on the gage (ambient temps of 50, no towing, light load in the bed). Others see this?



I also wonder about the large mass of brass from the AN fitting to the temperature probe. I wonder if I can get an accurate temperature without the probe being in moving fluid. After running for awhile I touched the pipe and it felt about 120 degrees, but the brass "T" that goes into the AN fitting was hardly warm at all. Any thoughts? If I remove the "T" and thread the sensor directly into the AN fitting, it may block too much fluid flow. Any thoughts?

 

[JimBob24]

I also bought the MASSDIESEL line with temp port. I had the DiPricol gauge & sender and I just screwed the sender directly in the brass fitting. I originally had my sender in a fitting in the trans oil pan. After moving it to the cooler line I see much quicker response and higher readings. Mine seems to function perfectly.



I think brass is a pretty good heat conductor and I am sure there is still good oil flow around the sender. Any oil trapped around the probe is probably heated up fairly quickly by the brass fitting too.



I see around 100 deg or so just cruising around with the tc locked most of the time. If I get in a lot of stop & go traffic the temps go up to 150 or more. I tested my unit by putting the trans in reverse and holding the brake, then added a little throttle to get the tc to heat up. I saw a fairly quick response on the temp gauge.



I did not have to gound my sender. The end of the tubing that connects to the cooler should be grounded. I think my sender instructions indicated you were not supposed to use teflon tape on the threads so it would be grounded. My sender was a 1/8" NPT, which is tapered and did not need sealing anyway.



Is it possible that the size and length of your temp probe may have completely sealed the opening of the port in the brass fitting preventing fluid from flowing into the brass housing???

 

[MMathewson]

JimBob,

Thanks for the reply. I have the DiPricol sensor just like you, so I doubt I would have had problems with the oil flow or sealing the port. I didn't use teflon tape either. Perhaps I have a gage or wiring problem. I'll try the reverse test and see if I can get it to work.

 

[MMathewson]

Update with Gage Problem

Looks like my sensor is fine (6000 ohms at 50 degrees), the wiring is fine too. Checked the wiring at the back of the gage and I'm getting my 12 volts plus the resistance from the sensor. Still no dice. Either the gage is bad or I wired it wrong.



If someone else still has the instructions for the Di-procol transmission gage, please let me know. I wired the Gnd to Gnd, "B" to +12Volts, and "T" to the sensor.



Thanks