Parts Needed To Tow a Trailer with Brakes Using a 2011 BMW X5 50i

Updated 08/28/2019 | Published 08/27/2019

Products Featured in This Question

Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector

(1905)

$87.95

Curt Trailer Hitch Receiver - Custom Fit - Class III - 2"

(197)

$275.23

Curt Echo Wireless Brake Controller - 7-Way Plug-in w/ Bluetooth App - Up to 2 Axles - Proportional

(1836)

$289.95

7-Way RV Upgrade Kit for Trailer Brake Controller Installation - 12 Gauge Wires

(367)

$90.91

Question:

I have a 2011 BMW X5 50i with no towing package. I plan to purchase a small trailer, such as am Airstream Bambi with trailer brakes. Im assuming small trailers with brakes have electric brakes and need a compatible wiring harness hook-up. as opposed to momentum brakes that dont require wiring beyond light hook-ups. What parts do I need for this? I read from one of your posts that a vehicle with a standard 4-pin wiring hardness that is spliced into the tow vehicles light wiring can be adapted to a 7-pin harness that allows electric brakes. Is this correct? So theres no special wiring need for a 7-pin set-up? Thanks,

asked by: Mark G

Expert Reply:

The Airstream Bambi does indeed have electric trailer brakes so in order to activate these with your 2011 BMW X5 50i you will need a 4-way trailer connector, 4 to 7-way trailer connector adapter, and a brake controller. This will cover all the brake and lighting requirements but you will also need a trailer hitch which I am sure you were aware of.

The route we are going to take will be to first install a 4-way, the Curt Powered Tail Light Converter part # C59236. Once this is installed we can then adapt this to a 7-way, the 7-Way RV Upgrade Kit for Trailer Brake Controller Installation part # ETBC7L. Once this is installed the only other thing you will need for this part is a brake controller, the Curt Echo Mobile Trailer Brake Controller part # C51180.

The Curt Powered Tail Light Converter will splice in behind the tail lights. The 7-Way RV Upgrade Kit will then plug into the Curt Powered Tail Light Converter. The reason I recommend the Curt Echo is because it cuts down on install time dramatically because you don't have to run any wires into the vehicle, splice into the stop light switch circuit behind your brake pedal, or run power wires from the cab to the battery.

For a trailer hitch, the Curt Trailer Hitch Receiver part # 13077 is what I recommend as they tend to be a bit better quality than their Draw-Tite counterpart therefore installation goes smoother. I have attached an install video/photo on this for you as well.