I have found a F350 equipted like I would need for towing our new fifth-wheel. I know nothing about ford. Does the Tranny have tow haul mode? is there an exhaust break? The truck is 4x4 with the fith-wheel goose neck towing package ( puck system). Will this truck have a locking rear end or is that an option that needs to be added at the factory? This F350 has about 85% of the stuff of the truck I ordered out from GMC dealer.
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The F350 depends on the year of manufacture. Prior to mid 2011 avoid, after that they have the excellent Ford 6.7 L diesel engine, assuming you are looking at a diesel, which you should be.
Post 2011 1/2 they have engine braking(the newest models have an improved control system for engine braking-maybe 2015 models and newer), they use DEF, they have tow-haul mode. The truck might have the factory installed fifth wheel prep which is excellent. I am not aware if there is a separate gooseneck/fifth wheel prep but I suspect they are one and the same. This gives you a flat truck bed when the hitch is removed and make hitch install/removal a 5 minute process. Do NOT use a gooseneck hitch with your fiver, fivers are not made with that in mind and it can overload the frame ajnd void the warranty. We have hauled our 34 ft fiver all over the country, including up and down the western mountains multiple times, and generally you can hardy tell you are hauling a big fiver unless you look in the mirror.
The newest models added another hundred or so HP but the 2012 have plenty of power and torque. Go to your Ford dealer and test drive one.