Gear/Trans temp issue

So... I believe I "accidently" was on part of the old Rubicon trailhead, and slowly worked my way through it (I was moving to a location to do some Astro-photography).

I was pleasantly surprised that the Tundra was able to "fit" through the section that I went through, however I quickly became concerned with engine/trans temp.

It was ~55-60* outside
I was REALLY babying the vehicle
4wd High / Low
Trans temp gauge was nearly maxed, I could smell "coolant"

There no shot this is normal right? I can only imagine how hot it would get in traffic hauling a trailer. Is this a concern or operating as intended?

They really should have adjusted where "hot" is on the gauge if its normal imho