When you go and trade in your vehicle you are rarely gonna get whats owed on it unless its less than three years old. Once you go over three years you are upside down on your equity vs whahts owed.
Call the library or a bank and ask what the loaan value is on your truck. Thats what you will get for the vehicle no matter how much it is worth in sentimental value to you or anyone else. I worked at a dealership for a while thats why Im saying this.
As far as what to choose, Id personally take the 4runner. But Im also in my days of liking a smooth, comfortable ride which is somewhat easy on gas. I remember driving a truck one day to another dealership and telling myself id never get a truck unless I was making 100k + a year bc gas guzzling is ridiculous on those things.
The thing you need to figure out is wether its cost effective to get a new vehicle. In other words, figure out the cost of having both vehicles on a monthly basis. Figure in the note, insurance, gas used, and normal wear and tear. Also factor in how much is it worth to you to have the extra room in a vehicle. If its worth the extra dough to get the 4Runner then youve made your decision. Just remember that gas prices will continue to rise so make sure you keep that in mind.
-sasap