The simplest way would be to use a grinder with a cutting disc and just cut the pipe off.
Under the hood, under the battery theres the Transmission Dipstick... Just pull it out, take a long like funnel, put it on and fill it up.
IT is made to reflect sound back to the muffler to cancel sound out, so the sound you hear is what dodge wants you to hear. if you take it off, your factory muffler will sound like, loud, but you can get a singel after market muffler that is quiet with out the resonator.Even a new oem muffler will be loud, so go with an after market that works alone with out the resonator. Rember its a family van. Quiet is better.
Take out the transmission
5w30 or 10w30
5w30 or 10w30
you have a vacum leak on your throttle body
take to muffler shop
22
10w30. Sometimes its stamped somewhere on the dipstick too
Automatic uses ATF+3 or +4.
A free flow muffler can improve mileage but by not by much. It would take a long time to recoup the cost of a new muffler.
cuz