What Base Plate and Wiring do I Need to Flat Tow My 2025 Jeep Grand Cherokee L Summit?

Updated 02/16/2026 | Published 02/04/2026

Products Featured in This Question

Roadmaster InvisiBrake Flat Tow Brake System - Preset

(286)

$1380.00

Demco Tabless Base Plate Kit - Removable Arms

(389)

$466.87

Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Coiled Adapter Cord

(3250)

$189.08

Roadmaster Battery Charge Line Kit for Towed Vehicles

(1236)

$42.89

RoadMaster Stop Light Switch Kit

(634)

$49.72

Question:

I purchased a 2025 Grand Cherokee L Summit with no lower active shutter. It just has middle and upper shutter. I see the Demco base plate works, My questions are. Will the roadmaster Rm-15267 work with LED Taillights? Also, Does the Roadmaster Invisibrake need the Vacuum line installed? talked to someone from roadmaster and they mentioned the new Jeeps GC dont need vacuum . Also if i dont do a monitor screen in the Rv, do i still need the Stop Light Switch. Thanks in advance

asked by: Ovi C

Expert Reply:

Hello Ovi,

Happy to help clear things up for you!

Starting with the base plate, you are correct. The Demco Tabless Base Plate Kit with Removable Arms # DM46GV is a great fit for your 2025 Jeep Grand Cherokee L Summit, since your vehicle does not have the lower active shutter. This allows for a clean installation with removable arms when you’re not towing.

For the wiring you will indeed want to use the Roadmaster 4-Diode Universal Wiring Kit for Towed Vehicles - 7-Way to 6-Way Coiled Adapter Cord # RM-15267, it will work great with your LED tail lights. I double checked with Roadmaster, you do not need the smart diodes. You will also want to install the Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25, this keeps your towed vehcile battery charged while flat towing. No one wants to get to their destination with a dead battery.

Regarding the InvisiBrake vacuum line, the Roadmaster InvisiBrake # RM-8700 is designed to work with power-assisted brakes and typically uses a vacuum connection to prevent the brake pedal from feeling dead during braking. If your Jeep is equipped with a traditional vacuum-assisted brake booster and a usable vacuum line is present, the vacuum tee and check valve should be installed. However, many newer Grand Cherokee L models use an electric or hydraulic brake booster and do not have a usable vacuum source. In that case, the vacuum connection is not required and should be omitted. Installing it this way keeps the setup clean and avoids unnecessary components under the hood. I wish I had a more direct answer, but we have not installed this on a 2025 at this time.

Lastly, regarding the stop light switch, even if you are not using a monitor or indicator screen in the RV, the Roadmaster Stop Light Switch Kit # RM77RR is still required. This switch provides the braking system with a dedicated and consistent signal that confirms when the Jeep’s brake pedal is being applied, allowing the InvisiBrake to operate predictably and reliably every time you tow without the need for later adjustments.

I attached a great help article on the "Must-Have Flat Towing Components," it is a great read whether you are flat towing pro, or just getting started. If you would like to give me a complete list of what you have, I am happy to look it all over for you.

What RV will you be towing with? Are you new to flat towing, or upgrading from a previous setup? And once everything is installed, where are you planning to take the Jeep for your first trip?

expert reply by: Kate F

Larrym

2/10/2026

I installed the Invisabrake on our Jeep GC, no vacuum line needed since it has electronic brake assist. I also installed the stop light on dash of our RV. It is really nice having that light so you can see when the brakes are active. System was easy to adjust the braking force too. We did all Roadmaster tow bar and base plate.