hi if your pulling a lot of weight you need gearing all the profmance mods that you can do are not going to impact you towing like the gear raito will. With 33 and heavy towing you need around 4.10 to 4.56 geras.
Towing requiers high rpms in a rever like the 5.4l
i have and 03 sd extra cab long bed 4x4, with the 5.4.I regrly pull loads at the max gcvwr and have no problem with exceleraton or merging and runnig 70+ mph on the high way.I recently redid the top end with trick flow twisted wedge cylinder heads, comp cam,and profmance 5.4 intake. i run 38 in super swamper ssr with a 6 in lift with 5.13 gears and detroit lockers front and back. But, the most noticebale up grade is the 5.13 gear. Without the gearing even with all the mod my truck would be a pig.
On a budget you can get front and rear gears with the install kits fo around $600. If you are mechanicly inclined just read up an r&p swaps and take you time and do it your self. Programers are good but in my opinon on a gas motor dont do much. Unless you have engine mods and get a custom program to match.I use a deoblo tunes with a custom progam from from rpm outlet ( THE MUSTANG GUYS). Most of your upgrades will come from mustang guys doing 5.4l swaps. Cuase truck guys now adays are mostly running hopped up powerstokes. I perfer the 5.4 for the rpms and weight advntage. I will hook bummpers with any powr stroke out there and beat most in a tug of war. And off road the less weight on the front end and overall lets me go places they can't. Good luck and ther is always a suppercharger
pic and dyno sheet coming soon !