No. The F350 will not be able to safely tow 24 000lbs. At most, with the weight of the trailer (fifth wheel configuration) it will safely tow 16,200 (4x4). That's with a 4.10 rear axle ratio (you should be able to find your axle ratio posted in the glove box). If you have a conventional trailer (king pin configuration), you can tow a maximum of 12 000lbs. The towing capacities are rated by the strength of the trucks frame.
You can tow more with a fifth wheels as the weight is distributed directly over the rear axle, as a conventional trailer hangs off the end of the frame, decreasing capacity. To safely tow 24K lbs, you will require a class 7 or 8 truck.
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1993 Dodge Spirit 2.5L TBI, 100hp
1999 Ford Taurus 2V 3.0L, 145hp
2000 Dodge Durango 360, approx. 285hp @ crank
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