Should I trade in my 2006 Jeep Grand Cherokee Overland for something newer and more

fuel efficent? We are a 1 vehicle family for now, and our Jeep has 52K miles I am worried that the value is going to sink even faster now with gas prices, so would it be wise to trade it in now and get something with a few less miles? My wifes concern is that it is a nice vehicle, Navi, rear DVD, etc, and we should just get a cheap fuel effiecnt car for short term like a sturn and keep the Jeep. I just dont want to have the Jeep worth nothing and try to trade it in. Please give some advice