02 jeep liberty 112,00miles. Dropped pan and changed filter. Filled w/ 5qts of the Mercon trans. fluid. The guy at the parts store said it was okay but found out the next day that it was bad. One guy at the local mech. shop said they use reg. trans +4 or +3fluid and use an additive. What should I do.
1-top off with mopar stuff and forget it.
2-topp off with mopar stuff and put the additive in.
3-drain and replace w/ mopar stuff.
4-drain and replace w/ mopar stuff and additive
5-pay 140bucks for the dodge dealership to do it.

I am not familiar with the differences between Mercon and the chrysler stuff. I would personally do 3, 4, or 5.

Chrysler transmissions are picky about fluid. - Your 02 Liberty has a 45RFE trans - they really need to run the ATF+4 - the Mercon is going to cause shuddering, and will not hold up well. I'd get it flushed personally, to make sure that you get all the old fluid out. Just my 2cents. I'd also drop the pan and replace both of the filters just to be safe. That may be overkill, but it's cheaper in the long run than possibly having the trans go south!

In 02 it was the 545RFE(5 speed tranny, most people can't feel the extra gear though). The MERCON fluid will wreak havoc on a CHRYSLER tranny, ONLY ATF+4 should be used in it. If it were me, I would have it flushed with +4 fluid. A simple drop the pan and drain and fill will not get enough of the MERCON out. You really need to have it flushed to get it out of there. Make the guy at the parts store pay for his SEVERELY bad advice.

got it flushed today...thanks

Chrysler transmissions are picky about fluid. - Your 02 Liberty has a 45RFE trans - they really need to run the ATF+4 - the Mercon is going to cause shuddering, and will not hold up well. I'd get it flushed personally, to make sure that you get all the old fluid out. Just my 2cents. I'd also drop the pan and replace both of the filters just to be safe. That may be overkill, but it's cheaper in the long run than possibly having the trans go south!
X2, Chrysler is very fussy about their fluids. ATF-4 is the best bet. I would not recommend replacing the small screw on filter by the valve body, that is onle to be changed during a rebuild.