Trailer hookup, tried Pep Boys, Advance & several others.
on 1999 Ford Explorer

I have a six wire pre-wired system, located behind the passenger rear bumper. Cannot find a harness anywhere.

Asked by for the 1999 Ford Explorer
Did you try NAPA? Take it to them and let the parts people look at it if you have a store in your area.
Haven't tried NAPA yet. Did call Chapman Ford & was told they no longer make them due to not enough sales of the part.
NAPA has a line of parts called Balkamp that has more stuff than most all other parts stores put together! If an aftermarket part is available they have it. One more place to look is ebay motors, somebody has one!
2 more answers , 2 more comments
or even a u haul rental store
That's next on my list. Last resort is to hardwire it myself.
If NAPA doesn't have what you need , maybe there is a trailer/motorhome sales in your area. Anyplace that does installations is more likely to have a variety of harness adapters.
I have tried a trailer hitch installer in Bensalem, no luck.
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