bing tracking image

Curt T-Connector Vehicle Wiring Harness Installation - 2018 Jeep Grand Cherokee

content loading

Customers compare C55774 to these similar products

Products Featured in this Video

How to Install the Curt T-Connector Vehicle Wiring Harness on a 2018 Jeep Grand Cherokee

Speaker 1: Today, in this 2018 Jeep Grand Cherokee, we'll be having a look at and showing you how to install Curt T-Connector Vehicle Wiring Harness for factory tow package vehicles with a seven blade four pole flat connector, part number C55774.Here's what a wiring looks like installed. As you'll notice, we have a seven-way connector here, and this will give us all the functions that we need in order to tow a trailer. We'll have turn signals, brake lights, running lights, a 12-volt charge line, reverse light output, which is useful if you're towing a boat trailer with a reverse lockout cylinoid. And we even have the ability to control electric trailer brakes, provided we have a brake controller installed on our vehicle.We also have four pole flat connector here, so if you're just towing a small trailer, which you only need to have lights, it'll get your tail lights, your brake lights, and your turn signals off of this connector.Now, what's great about this wiring harness compared to others on the market is, not only do we have the seven-way, but we have the four-way as well. So, we don't need to worry about running an adaptor in our seven-way just to tow a standard trailer with a four pole flat connector. We have the ability to do both.Another nice thing about this wiring harness is that it utilizes what's already on your vehicle from the factory.

There's no cutting or splicing required. It's direct plug and play for your Grand Cherokee.Now that we've gone over some features, we'll show you how to get it installed. We find ourselves at the back of our Jeep right now. We need to find a place to mount our bracket that'll hold our seven-way connector. Our hitch has an attachment point built into it to attach this bracket.

So, we'll sit it over it, ad we'll attach it with screws and nuts.Now, we'll just tighten down the hardware using a screwdriver and a wrench. Now, we'll take our seven-way connector, we'll feed the vehicle end through the hole, same with our four pole flat, and we'll take the hardware that comes with the kit, put our screw on. Then, we'll have a flat washer on the back side, a lock washer. And we'll screw on a nut.We'll do the same for all four corners. With all of our hardware now in place, we'll use a wrench and a screwdriver to tighten it.

We'll take our four pole, we'll slide it into this groove, take our dust cover, and we can close it.Now, if we look up above where we mounted our connector, we see our factory tow package connector right here. We need to pry this away from the bumper. I'll use a trim panel took for this. And we can pull it out where we can work with it. There's a tab right here.

We press in on this tab. We can now grab this dummy plug, and pull it out, and have access to our connection.Now, I'll take some dielectric grease, which we have available on our website, and I'll put it inside our connector here. This will just help better protect it from the elements. We'll take our new connector, match the two ends up, push it in until it locks in place.With our connection made, we can now take our connector, and stick it back over our hitch, and secure it into place.Okay, now that we have our connector installed, there is one final thing that you're more than likely going to have to do. Most Jeep Grand Cherokees out there will require to have the computer re-flashed at the dealership in order for the connector to work properly. This can readily be done at all dealerships for a minimal fee.And that completes our look at and showing you how to install the Curt T-Connector Vehicle Wiring Harness for factory tow package vehicles with a seven-way and a four pole flat connector, part number C55774, on this 2018 Jeep Grand Cherokee.

Andy M.


I am adding an after market hitch with this harness for my 2018 jgc Laredo. do I have to wait till I plug in this harness or can I get the reflash done now ?

Etrailer Expert

Jon G.


Good question. I believe it's after you have the wiring harness plugged in so that the system recognizes it, but that would be a question better addressed by your local Jeep dealer since they know more about what all happens with the reflashing.

Info for this part was:

Employee Andrew K
Video by:
Andrew K
Employee Joshua S
Video by:
Joshua S
Employee Dustin K
Video by:
Dustin K
Employee Michael B
Video by:
Michael B
Employee Jeff D
Installed by:
Jeff D
Employee Jacob T
Video Edited:
Jacob T
Employee Chris R
Video Edited:
Chris R
Employee Brent H
Test Fit:
Brent H
Employee Shane H
Test Fit:
Shane H
Employee David F
Test Fit:
David F

At we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.