2000 Caravan. 121,000 miles. Well maintained.

Is it worth it to switch to synthetic at this point? Am I risking more problems than what it is worth?

 

I would go ahead and switch but there are more opinions than mine about this.

Here's a link that will help.
http://www.bobistheoilguy.com/

My thoughts are you will probably get a leak at some of the seals due to detergent differences between oils.This causes the deposits that are working with the seals to get cleaned off the moving part and starts a leak.After time,new deposits will reseal the leak and all should be well again.
You could try blending your own lube oil by using one quart of the new oil along with the rest being the oil you've always used.Run this for one or two oil changes and if there are no major puddles or oil loss between changes you can up the ratio at the next oil change.
I don't think this added confusion is necessary but it could be a carefull approach.
One thing though,once the old deposits are cleaned off it will take time to get them back into position to help with the job of sealing the engine.
I've used as many different oils as you can think of when changing the oil in my wife's '92 Caravan 3.3 and I don't have any big leaks.Oil consumption is a little over a quart in 5,000 miles even with 133,000 miles.

 

Personaly, I wouldn't bother unless you live in a very hot or very cold climate. Synthetic oils flow better at cold temps and withstand very high stresses at hot or heavy duty conditions. There are some downsides--higher oil consumption, increased tendency to leak, and really nasty depsits on valves if you burn any oil at all. Plus it costs a lot more.

 

I wouln't bother at this point