Originally Posted by goduc
I would suggest you try a ScanGage for your temps. The coolant temp has nothing to do with the tranny temp. Two examples.
My 08 F150 had the typical C-H gauge. I used a ScanGage in it. The SG will show both temps at the same time. You could see the tranny and coolant temps rise even though the needle didn't.
Also on my current 12 Ram CTD I have an in dash readout. I only have a coolant temp gauge on the instrument cluster. When I switch the EVIC to show the different temps it will show the coolant at 201 and the tranny at 140-160 depending on ambient temps.
One time while driving up a steep winding hwy for about 15 miles the running between 20-35mph towing our 5th wheel, the tranny temp went from the normal 160 tow temp to over 200, while the coolant temp barely rose.
Point of all this is your tranny temps while influenced by the coolant temp are going to rise individually.
You may be correct somewhat. MY 08 F150s coolant temp gauge never rose when towing up mtn passes even though the SG showed the temps rising. Under normal operating the gauge needle went to the normal and stayed there.
My 12 Ram CTD gauge will rise as the temps rise. So maybe your Nissan gauge is right and isn't rising.
JMO though is I'd invest in a Scangage to make sure of your temps.
goduc... Just heard back from ScanGauge regarding its ability to monitor the transmission temperature on my 2014 Frontier. Here is their reply:
"Unfortunately, we do not have transmission temperature available for Nissan. Nissan has a special handshake request for reporting enhanced sensors. On top of that some of Nissans vehicles appear to use a non-CAN based protocol to report enhanced information. Because of this, it makes it difficult to access enhanced sensors like transmission temperature. If you have any questions, please let me know.
Repairs and Technical Support
Looks like I'll have to depend on the truck's temp gauge, even though you pointed out it isn't too reliable an indicator with regards to the transmission, and keeping an eye on the transmission's fluid color. I still plan to change fluid every 25k!