I have a 01 Dodge Ram, but it has the 3.9L in it so i figured you guys could help me out.

I changed my oil last month and i usually put 5quarts in it. I checked it the other day and it's way overfilled. Whats the deal? Do i need to drain some oil before some major damage happens?

Also, my oil pressure guage goes up down. When i start it it's right past the second hash mark then when i get on the gas it goes to right before the third hash mark. It's getting 17mpg, and i'm not losing any power.

 

The 3.9L "oil with filter" spec is 4.5 quarts of fluid.
Yes, you should drain some of that oil, and get it back down to the line. Running with the oil level too high can cause damage.

It's normal for engine oil pressure to rise with an increase in engine speed. No problem there.

 

Too much oil can do major damage. In the most extreme case it could cause oil foaming from the crank constantly running in oil which can lead to oil starvation on the bearings. It is also hard on seals.