Trailer Wiring

[71PA_Highboy]

What is most common AFTER the flat 4 - 6 or 7 wire?

I see adapters for 7 wire to 6 and flat 4, so it seems that may be the most versatile solution.

Comments?

[Bummer72]

Most often, on most trailers with anything more than lights, the round 7-wire harness is most common. This will allow you the running lights, L and R turn lights, brake lights, as well as the added function of trailer brake, an auxiliary 12volt line, and reverse lights for your trailer.

It's all standardized, so as long as you wire your truck to the standard, you should be able to hook into and tow any trailer also wired to the same standard.

[fireguywtc]

It has been my experience is that seven wire is most common with brakes then the flat four without brakes. I don't see six anymore. You are correct that there are adaptors so that is a good solution. Also, I bought a dual purpose plug in for my 70 that has both the flat four and seven. It was wired together so you only have to hook up one set of wires. In other words the four way is wired into the seven way in the outlet before where you wire it to the harness. That way you will only have to buy a seven to six adaptor if you need it. The outlet I bought was about $25 at Advance auto IIRC.