[jfaberna]

I agree, you want to make sure. I sat down with my dealer's commercial truck dude and we went to the Manufacturer's website and pulled down the towing spec for their trucks for that model year.

It's a long list with every model they make. You need to know the transmission type, axle ratio, etc. along with the stuff on your door sticker. There is no math involved with using that table. For example on my truck under the model of mine was an entry for each transmission model and axle gear and just found mine and looked at the 5th wheel towing column.

The one caveat you need to think about is that table is based on a few assumed facts like nothing in the truck or bed except for one 154lb driver. So I had to add 100lfb for me, and more weight for the DW, any pets, generator, toolbox, extra fuel tanks, etc.

In my case was 200lb over the limit prior to adding the normal stuff you need in a truck when towing, so I had to order a DRW and increase the axle ratio to 3.73