5.0GN tow

No I don't work for any of those companies, though some my relatives do work for one or more of them. I just spent some time researching. I design weapons components so I deal with metallurgy a lot and this kind of stuff intrigues me.

I agree that a superduty would be the easy solution and even posted earlier, it's easier to buy a bigger truck. You can also, as I stated have a certified upfitter recertify the truck, not easy or inexpensive but it can be done. Shops that specialize in that work do it everyday when they mod trucks for jobs they were not intended to do, but can be set up to do. Industry uses trucks well beyond original design specs, and these shops set them up to do it and certify them, it's the only way they can be used in many cases. Think of bucket trucks, railroad trucks, other similar types of uses. The trucks get upgraded suspensions, increased gvwr and gawr and new stickers to go with it. Those companies can also do 1/2 ton trucks, I checked and may send mine to one of them next year if I upgrade my trailer.

SkiSmuggs

You can add SuperSprings and Bilstein HD shocks like I did to my 2011 Max Tow Ecoboost, but your complaint is lack of power. You can get more towing capacity when you buy the truck. I got Max Tow because I bought the truck to tow 10,000 lbs and it did that pretty well. Unfortunately, the sales guys usually don't know jack and it is up to you to do the research.
The rule is that if it isn't done at the factory, it doesn't change your payload sticker. The reality is that Ford added an overload spring and HD shocks to raise the payload (thicker frame and heavier axle too), so theoretically it should help and did for me.
In summary, you can get another F150 with Max Tow and HD Payload (special order) or an F250.

5.0GN tow

The only way it can change the payload sticker is by a certified upfitter, they are approved to do it. They charge a lot more but they are accepting liability for their work in return for it.

All the 163 and 156 WB trucks get the same thicker frame per the sourcebook. The 144.5 WB trucks use a 49.3k yield strength, higher RBM frame. A slightly less strong RBM frame was used on the 126WB trucks, but they are shorter so less prone to deflection and heavy loading just due to size limitations.

Spring packages were different and shocks most likely too, but the axle for 9.75 is the same spline count with heavier duty 7 lug wheels. All the info is in the ford sourcebook. The same axle is used on the newer trucks with 6 lug wheels at a higher rating. It's the lowest rated part that sets the rating for an axle. It's usually either springs, wheels or tires.

Ronpurdue

Thanks guys...I think for now I'll just keep my(father in laws) smaller camper and look to upgrade trucks in few years with camper.

I think I will get overload springs vs leaf ...to help with payload now which is on the boarder..

Boulevard

I have a 2013 F150 XLT with the 5.0 and 3.55 gears. I have a tow rating of 7300lbs and a payload of 1440lbs so we are pretty much the same truck. I tow 6000lbs with a tongue weight of 500lbs and I have 600lbs of cargo in the truck....I am not exceeding any limits and the truck pulls like a horse all the way to a comfortable 70mph. Honestly, I simply do not see the problem with what you are doing but if you do feel the need to mod than a better set of shocks will go a long way to helping and a ladder bar will stop the axle wrap dead in its tracks. Other than that leave it alone.

Well set up high quality hitching will do more to improve your towing experience than any other thing that you can do. Stay away from anything under $500.00.

All supercrew F150's use the 9.75 diff and they all have the heavy duty frame.

nihilus

Replacing 20" pimp wheels with lighter 17" or 18" tires might help. Being under warranty I guess you do not want to tune, but it would help ALOT. These are the guys I used:
http://www.morepowertuning.com/ecoboost-f150
Gears seem like a waste. Lock out 6th gear on a 3.55 and it will be like using 2nd-6th gear with a 4.10

Do not put on a dopey leveling kit.

Williambarrettclark

Feathermerchant if you don't mind I need some info! I have a 2012 XLT 4x4 super crew with the ecoboost 3.55 gears and I have already flattened one set of leaf springs under the factory warranty and now I've done the same thing. I have already talked to my local service department and they have talked to ford and ford said if I can get the option code for the spring and a complete vin of the vehicle the springs are on they will let me put the HD springs on my truck so I don't have to change them out every 30000 miles! Any info will be greatly appreciated

Feathermerchant

All the info you should need is on the pic above. Even the VIN.