I will be doing some moderate towing. Yes I know it is not encouraged but i am relocating and am towing a small trailer. I am installing a transmission cooler but I also want to monitor temp.

I bought this first which is a gauge:


but now I am reading about OBD2 scanner and am thinking this should work? Is this accurate enough to consistently monitor my tranny temp while driving?

 

You need a pro to install the gauge. I don't think it is worth bothering with either of your suggestions. Just get the fluid changed and have the car inspected. Make sure all fluids and filters are good and tires inflated higher than what is on the door jam. Maybe 35 pounds each.

If you must, an OBD2 scanner is probably the way to, but I am not don't know if you can use it while driving. Most are used for diagnosis and changing settings while working on the car. You would also have to mount it somewhere.
I would do some youtube searching on using an OBD scanner on a Toyota - Lexus.

Search this forum, others have asked about towing. See this recent thread: https://www.clublexus.com/forums/es-...-ma-to-ca.html

How far to you plan to tow? Are hills-mountains involved? Desert heat?

 

thanks for the reply. I did some more research and found the scangauge 2 gives real time monitoring of Transmission fluid temp, etc. so I bought one and should be good to go with this. My mechanic is installing the transmission cooler and doing a full inspection before I go. I’ve let him know my intentions and he had no concerns but I will be extra cautious.

 

I've got the Foxwell 510 Elite. does a great job of checking tran temp. it buried in there, but its there.