I am new to the forum and have a question about my 2011 SR5. Great vehicle with 40k miles no problems so far except for a concern last week when my wife and I were driving on the ocean beach (Outer Banks NC) rather soft sand. I shifted into 4WD-H and after a short beach run the vehicle began making popping/thumping sound in the front drive train. It was at night and light cold rain so we left the beach. The next day, in the light of day we were on the beach again and similar noise reoccurred. It almost sounded as if the hubs were not fully locked and was very noticeable when stress was applied like trying to leave the beach. I shifted into 4WD-L and the noise stopped and operated like the Suburbans and Jeeps I have owned. Has anyone experienced similar issue?

In 4Hi the traction control is still enabled so that was probably the sound you heard. In 4Lo it's disabled which is why you didn't hear it.

I read about that in the manual. I pushed the "Trac -A" button on the ceiling but could not make sense of it with the dash icon (did not see icon lit indicating it was either off or on). Will pay careful attention next beach ride.

The A-TRAC button can only be used in 4LO, so if you pushed it and were in 2 or 4HI you would not see the indicator on your dash. As such, by default it is always off.

The VSC can be turned on and off in 2 or 4Hi. That button, at least on my Trial, is near the A-TRAC. I believe it is a picture of a car with two wavy lines.

Thanks to all for your help