I need to know if my OEM hitch is a class 3 or 4....

 

You need to just forget about what class it is and go by the reccomended pulling weight. I wouldn't tow anything over 9,000lbs or anything over 6,000lbs unless properly equipt(weight ditribution hitch)

Sounds right away like your towing too much....??

HERE is the link to the Faq section Thread of Weight limits.

 

My truck has a Mopar and the tag says MAX trailer weight : wieght distributing 12,000 weight carrying 5,000. MAX tongue weight: weight distributing 1,200 weight carrying 500

 

Why would you think he is towing too much? He was just wondering what class he has. BTW, it's 4.

 

Class IV is usually what comes in the tow package, still get down there and check it out to be sure that yours wasn't an add-on at the dealership or added later if you didn't buy it new.