Towing capacity is set from the manufacturer with the various options packages offered for your model year, can't really be increased. If yours wasn't optioned with the HD trailer tow package, your capacity will be lower than the advertised 9200 lbs. You can add things like a tranny cooler, change the gearing, add 7 pin connector, programmer for the motor, intake, exhaust, WD hitch, but none of that will increase the set capacity, just overall driveability. We need to know how your vehicle was optioned to give better answers, ie standard towing vs. heavy duty trailer tow. If you have HD trailer tow, you already have some of the goodies.