Adapter and 7-Way Recommendation to Connect Peterbilt to Trailer with Combined Taillights

Updated 04/08/2019 | Published 04/06/2019

Products Featured in This Question

Pollak 7-Pole, RV-Style Trailer Connector Socket w/ Wiring Harness and Mounting Bracket

(100)

$44.45

Roadmaster Brite-Lite 3-to-2 Tail Light Converter for Towed Vehicles

(120)

$64.90

Question:

I want to know the best/ easiest way to make the Peterbilt which has air brakes with round style plug to hook up to a equipment trailer which has a normal light duty 7 way spade plug,.... I didn’t realize how the truck with air brakes uses it’s own stop wire, this making my life hard to try to begin to make everything work with my smaller electrical brake equipment trailer. I have a Hopkins impluse electrics brake controller and adapter ends for each different trailing end...truck to a round 7 male and a spade 7 female to the electrical trailer stock male end. I’m thinking if I use a converter in the middle of this adapter which is little tricky to think about hooking up to other disssimular trailers, That should work for this set up. I am pretty sure you have seen this before, would love to know your thoughts thank you, possibly description or video would be very helpful thank you so much! ... my main issue being I can’t have a turn and a stop wire together, unless I have some sort of converter, while still operating the electrical brakes, I have every light functional but the , trailer stop lamp currently and I am using the electrical brakes which work perfectly, currently

asked by: Brian K

Expert Reply:

One of the frustrating differences between lighter duty trailer wiring and heavier duty trailer wiring is that the lighter duty setups have the stoplights combined on the same circuit as the turn signals whereas the heavier duty setups have them separate like you noted. There isn't an easy way to make this conversion but we do have converters that were designed for this like # RM-732.

So one solution would be to install a new 7-way blade connector on your truck with the # PK11898 and then use the adapter part # RM-732 on the wiring to the new 7-way so that it can work with your trailer.

expert reply by: Jameson C