Trailer Hitch and Powered Wiring Harness Recommendations for 2007 Mercedes-Benz ML350

Updated 06/29/2015 | Published 06/25/2015

Products Featured in This Question

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

(1705)

$80.71

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

(22)

$276.76

2" Hitch Ball - 1" Diameter x 2-1/8" Long Shank - Chrome - 7,500 lbs

(1360)

$11.31

Pin and Clip for 2" and 2-1/2" Hitches - 5/8" Diameter x 3-3/16" Span

(2940)

$4.58

Curt Ball Mount for 2" Hitches - 1" Rise, 2-1/4" Drop - 7-5/8" Long - 7,500 lbs

(3855)

$26.80

etrailer Trailer Hitch Receiver Lock for 2" Hitches - Flush - 2-5/8" Span - Chrome

(3606)

$24.04

Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires

(3418)

$127.95

Question:

Hi I am going to have a hitch and wire installed on my 2007 ML350. No LEDs on my truck and no air suspension either. I am towing a 20 year old tent trailer but want to upgrade later. Thing is, I am still deciding to go with a MB specific harness plus a SAM unit self installed then to have my dealership recode it. Or I can go with a powered converter. If I can, I would like to have charging on the 7 way plug but if not, I guess 4 way is ok too. What will limit my choices at this point and can it be done?

asked by: David

Expert Reply:

We offer several 2-inch Class III hitches for your 2007 Mercedes-Benz ML350 that can be seen on the link provided. All have the same capacities and will install pretty much identically. Each includes the required mounting hardware and each one will require a little drilling. I recommend the Curt # 13342 since it is the lowest cost option. Instructions are linked along with a helpful article on hitch installations.

The ball mount, hitch pin and clip are sold separately. I recommend ball mount # C45030, pin and clip # C21500 and either 2-inch hitch ball # 63845 or 2-5/16-inch ball # 63847. If you prefer to lock the ball mount to the hitch you can use # e98880 instead of the pin and clip.

An aftermarket wiring harness kit # C59236 will provide you with a 4-pole flat trailer connector that carries lighting signals only, but all you need to add for a 7-way set-up is our kit # ETBC7. This includes all the parts you need to convert the 4-pole on the Curt harness to a 7-way with 12V power for your trailer. Instructions and a video are linked to show you the installation process.

The advantage of a powered converter like the Curt # C59236 is that it will not use the ML350's wiring to deliver power to the trailer lights; the vehicle wiring acts only as a switch to tell the converter to draw power from the battery through the additional wire lead and fuse you will install. An article to help you with the routing of that wire is also linked.