I bought town and country last year.

This is about time to change oil.

1. can I use 5W30 instead of 5W20?

2. How many quarts shall I put in?

My T&C is touring with 3.8 engine.

I read an article that you should stay with to what's recommended in your owners manuel. Car industry are going more with the 5w30,but see what your manuel recommends.

The 3.8 takes 5qt with oil and filter change. 5w-20 is becomming more widely used due to its fuel saving characteristics ( thinner oil flows better). You can switch to 5w-30. the 3.8 is the exact same motor internally from a year or so when they recommended 5w-30. It was the same thing in my taurus. It wanted 5w-20 when the engine hadn't changed from the year previous when 5w-30 was recommended. You fine with either oil.