I am looking to get a 5th wheel camper.

Truck info: 2006 Ram 2500 Mega Cab 5.9L Cummins.

Tow capacity: 12,900 pounds...Payload: 1,670 pounds. 4 inch lift with 35s, Fox 2.0 shocks, Roadmaster Active Suspension System.

How much, if any, is towing/payload affected?

Can payload be increased by changing out the leaf springs or something else?

Thanks.