Smoke Coming From Back of Engine

I have a 1999 Tacoma PreRunner V6. I drove up a steep hill and noticed a burning smell and white smoke coming from the engine. Any ideas what the problem is and what needs replaced?

 

White smoke or steam? Oil?
What does it smell like?

Is your antifreeze low?

Could be any number of hoses that carry antifreeze in them

Or oil from the valve cover gaskets leaking on to the exhaust

 

My antifreeze levels are all up. I do think it could be some hose. It is steam.

 

steam is coolant you have a leak someplace.

heater hose or the valve is leaking

 

Is oil leaking onto the exhaust from the valve cover a common thing?

 

Sounds like a coolant leak from an intake manifold gasket or the "coolant bypass tube". Other sources already mentioned should be visible all the time.
A leak from the intake gasket or CBT will pool under the intake and eventually flow out the rear of the "valley" past a sheet metal plate and dribbling on the exhaust crossover pipe area. Leaks from these spots can be slow and go unnoticed for a long time until it gets bad enough to overflow out the back. In your case perhaps the "steep hill" aided in the overflow.
Shot of the "valley" area where the pooling occurs. Intake gaskets (left and right), coolant bypass tube in the center and sheet metal plate at very top center.
Yellow arrow is where the bypass tube fastens to the block, red is one of the coolant passages. Coolant tube is sealed with RTV, no gasket or o-ring.



Close up, tube removed.