And for refernce, on the 2018 F150's, what the OP has is a $95 option and nets:
Class IV Trailer Hitch
$95 S4
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Standard on LARIAT, King Ranch®, Platinum, and Limited. Included on XLT Mid and Luxury; optional on XL Base and Mid and XLT Base.
Includes:
• 4-pin/7-pin wiring harness
• Class IV trailer hitch receiver
• Smart Trailer Tow Connector
Versus the Trailer Tow Package which gets:
Trailer Tow Package
$995 S4
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Optional on XL, XLT, LARIAT, King Ranch®, Platinum, and Limited. Standard on Raptor (does not include Pro Trailer Backup Assist on Raptor).
Includes:
• 4-pin/7-pin wiring harness
• Auxiliary transmission oil cooler
• Class IV trailer hitch receiver
• Pro Trailer Backup Assist (not included on XL Base)
• Tailgate LED (standard on LARIAT and higher)
• Smart Trailer Tow Connector (standard on LARIAT and higher)
• Upgraded front stabilizer bar
Appears that the biggie is the transmission cooler...