I was leaving Coos Bay on monday and about 15 minutes into the drive my trans temp gauge spiked full hot, my check gage light came on, and my service engine soon light came on.

I checked the fluid and it wasn't hot to the touch at all, so I turned around and went back to the dealership in Coos Bay.

The service manager told me he was almost certain it's the transmission temp sending unit and that he couldn't get one until the next day, but it was safe to drive home. I drove home with my gauge lying to me and my tow/haul light blinking and scheduled an appointment at my local dealership for monday to have them deal with it.

My question is should I avoid driving the truck at all until then, or will it be ok? I wont be hauling anything.

Is there anything else I should have them check while they're in there?

This is on the 2003 in my signature. I checked the code and it was P0700.

And kind of off topic, but why does the light on the dash say "Check Gage?" Seriously, we couldn't get a u shoved in there?

 

Both gage and gauge are correct.

It is safe to drive the truck. It is almost certainly the temperature sensor. It has become a common failure.

There is nothing else that should be checked while this is being replaced.

 

So if I was reading trans temp from a digital gauge like the Edge CTS it would be giving me an incorrect reading, right?

I ask because I'm looking at buying gauges right now.

 

If you use an OBD scanning gauge like the Edge, it is going to give you the same data the PCM is reading. So yes, it would be incorrect because it is still using the same sensor.

If you go with a gauge with an independent sensor, then you get independent results. This is one of the benefits to add-on gauges over an OBD scanner. I still prefer my Edge.

The Edge might still be a good diagnostic tool in this instance, because you would probably see "off the chart" results which you know cannot be correct.