trans temp sender options
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From: Lake Nona, Florida
trans temp sender options
I'm seeing temp spikes towing and I'm wondering if the stock sender is really accurate. It was suggested that I put in a better gauge to check the stock sender (especially before I upgrade a tranny on that info).
Where are my choices to put a sender and what parts do I need to get? I hate to cut a T into a line... and make three places that can leak (my plumbing always seems to leak). Which line is which though? and which would I use? I also read there is a test port on the tranny? Where? What fitting might that take? Or maybe I could put something temporarily in the drain plug of my PML pan? Shopping for suggestions here if I try to get something in there quick before my next trip towing heavy...
Where are my choices to put a sender and what parts do I need to get? I hate to cut a T into a line... and make three places that can leak (my plumbing always seems to leak). Which line is which though? and which would I use? I also read there is a test port on the tranny? Where? What fitting might that take? Or maybe I could put something temporarily in the drain plug of my PML pan? Shopping for suggestions here if I try to get something in there quick before my next trip towing heavy...
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From: McDonough GA
The best place to put a sensor for the temp is in the cooler output line of the transmission. The pan and test port will ONLY read heat soak and not max temp. If your TC is slipping or not locking up correctly you WILL NOT be able see the results.
Never use the test port as it is worse yet for heat soak as there is no fluid flow, it is a dead end.
The pan is a better place and will tell you overall trans temp but the only indication you have of a problem is higher temps. The pan will read temps after the fluid is cooled and used for trans lube. Not enough info to determine where the problem is.
The hot line to the cooler is the best as you will see max temps from fluid coupling, and, you will see close to pan temps once the TC is in lockup mode.
On most of the later trucks the front cooler line had a 6" rubber vibration damper section in it. It is very easy to cut that line and splice into it. If your truck does not have that rubber line and it is solid, seriously consider getting the newer line as that is a recall item. The engine harmonics cause vibrations that will crack the fluid to fluid cooler on the block and dump coolant into your trans.
Never use the test port as it is worse yet for heat soak as there is no fluid flow, it is a dead end.
The pan is a better place and will tell you overall trans temp but the only indication you have of a problem is higher temps. The pan will read temps after the fluid is cooled and used for trans lube. Not enough info to determine where the problem is.
The hot line to the cooler is the best as you will see max temps from fluid coupling, and, you will see close to pan temps once the TC is in lockup mode.
On most of the later trucks the front cooler line had a 6" rubber vibration damper section in it. It is very easy to cut that line and splice into it. If your truck does not have that rubber line and it is solid, seriously consider getting the newer line as that is a recall item. The engine harmonics cause vibrations that will crack the fluid to fluid cooler on the block and dump coolant into your trans.
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Joined: May 2007
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From: New Bern, NC
I put mine in the cooler line coming from the trans. It is the line coming out of the trans right by the bellhousing. That line new fromt the dealer ship only costs $11. So I bought one and modified it with -8 an fitting with 1/8 NPT port. But you can take the line to any shop that makes hoses and they should be able to put a fitting in it for you. Diesel Manor also sells the replacment cooler line, but I have less than half of their price in my setup.
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From: Lake Nona, Florida
The best place to put a sensor for the temp is in the cooler output line of the transmission. The pan and test port will ONLY read heat soak and not max temp. If your TC is slipping or not locking up correctly you WILL NOT be able see the results.
Never use the test port as it is worse yet for heat soak as there is no fluid flow, it is a dead end.
The pan is a better place and will tell you overall trans temp but the only indication you have of a problem is higher temps. The pan will read temps after the fluid is cooled and used for trans lube. Not enough info to determine where the problem is.
The hot line to the cooler is the best as you will see max temps from fluid coupling, and, you will see close to pan temps once the TC is in lockup mode.
On most of the later trucks the front cooler line had a 6" rubber vibration damper section in it. It is very easy to cut that line and splice into it. If your truck does not have that rubber line and it is solid, seriously consider getting the newer line as that is a recall item. The engine harmonics cause vibrations that will crack the fluid to fluid cooler on the block and dump coolant into your trans.
Never use the test port as it is worse yet for heat soak as there is no fluid flow, it is a dead end.
The pan is a better place and will tell you overall trans temp but the only indication you have of a problem is higher temps. The pan will read temps after the fluid is cooled and used for trans lube. Not enough info to determine where the problem is.
The hot line to the cooler is the best as you will see max temps from fluid coupling, and, you will see close to pan temps once the TC is in lockup mode.
On most of the later trucks the front cooler line had a 6" rubber vibration damper section in it. It is very easy to cut that line and splice into it. If your truck does not have that rubber line and it is solid, seriously consider getting the newer line as that is a recall item. The engine harmonics cause vibrations that will crack the fluid to fluid cooler on the block and dump coolant into your trans.
Your advice makes sense. btw today after heating up the truck running empty I compared the pan surface temp (IR thermo) to the gauge. The pan surface was 30 degrees cooler... Knowing the hottest temp makes sense.
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Joined: Jan 2004
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From: Texas
I cycled the tranny in the driveway to find the hot line. The line that is sold from diesel manor and all the pictures I have seen was the cooler of the two lines. I thought the sender was supposed to be in the hot line.
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Joined: Aug 2002
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From: Northern Virginia
Genos sells a dipstick sensor that slides down, of course, the dipstick until it hits the pan. I had one in my 03 truck and it worked fine. If you just keep in mind that the actual "Hot" line temps are about 20 or 30 degrees hotter than it is just fine. It will give you the same reading as one that you install in your pan. I have another that I will be installing in my current truck. Definitely the easiest sender to install......
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From: McDonough GA
Nope, the line they sell is for the front cooler line. Thats the hot line.
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I tapped into the hot line with this:
http://cgi.ebay.com/Swagelok-B-810-3...6#ht_500wt_902
It's the same fitting that DM has on their line.
http://cgi.ebay.com/Swagelok-B-810-3...6#ht_500wt_902
It's the same fitting that DM has on their line.
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From: McDonough GA
How did you measure the temp? When things are up to operating temp its probably only a 40-50 degree difference.
If you pulled the lines off and started the truck it would fluid out of the front connection and none out of the rear. The rear is cooler return and transmissions lube.
