5.0GN tow

The airbags wont increase the payload technically, but they will level the load and help it drive better. If you load the trailer right and keep the load inside to a minimum, you will probably be right at the max, but the truck will handle it fine.

Mike Up

Wow didn't realize this thread has been dead almost 4 years.

5.0GN tow

I pulled 8k all through the applachians with the 5.0 pictured above, it did very well. It would hold 70mph no issues, in 4th on most hills. I always locked out 6th and other than that just let the transmission do its job. 3500 to 4000 rpms is high end of torque for the 5.0. Its where its happy when working hard. It will not hurt it a bit.

Mike Up

Here's a tow review comparing my 2 near identical F150s, one with the 5.4L and one with the 5.0L.

Velosprout

Airbags only help eliminate some of the symptoms of being overloaded...they do not increase payload or suddenly make you within your limits. In fact, you will have to subtract the weight of the airbags from your payload, actually reducing your towing and cargo capacity.