It will make a pretty large difference what year/model your F 150 is and how much your trailer will weigh (loaded). I towed my Ultra-lite Rockwood (8,0000 lb) for over 80,000 miles with my 2004 F 150 5.4 and never had an issue with it though it was a bit under powered for high altitude towing (exclusively in Colorado) but even there it did the job just fine. Newer model years with the 6 speed tranny will make a big difference and even bigger difference would be the newer 5.0 engine or for the MOST difference, the 3.5 Ecoboost.
As with most half ton trucks keep a close eye on tongue weight because that's the specification you're MOST apt to exceed. Just be aware that brochure tongue weights are with an EMPTY trailer and meaningless. Take 15% of the trailers GVWR to determine the most your tongue will ever weigh.
Good luck with your decision / Skip
2011 F-150 HD Ecoboost 3.5 V6. 2550 payload, 17,100 GCVWR -
2004 F-150 HD (Traded after 80,000 towing miles)
2007 Rockwood 8314SS 34' travel trailer
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