What to Do w/ the Vacuum Line When Installing the Roadmaster InvisiBrake
Updated 01/19/2026 | Published 08/04/2024
Question:
I have a Demco Invibrake flat tow system part RM-8700 that I took out of my Jeep Wrangler and installed in my 2024 Ford Maverick. My question is: since the Maverick has electric brakes and does not need the vacuum line tapped into from the Demco Invibrake what do you do with the port on the back of the Demco Invibrake? Just plug it or leave it as is open?
asked by: Mark M
Expert Reply:
I took a look at the instructions for the Roadmaster InvisiBrake Flat Tow Brake System item # RM-8700. It states to "Leave the vacuum port as is and proceed to the next section"
I attached the installation instructions below. The section addressing the vacuum line is on page 11.
Product Page this Question was Asked From
Roadmaster InvisiBrake Flat Tow Brake System - Preset
- Flat Tow Brake System
- Brake Systems
- Pre-Set System
- One-Time Setup
- Vehicle Battery
- Fixed System
- Power Assist Brake Compatible
- Air Brakes
- Hydraulic Brakes
- Indicator Lights
- Roadmaster
more information >
Featured Help Information
Instructions
Continue Researching
- Shop: RV Covers
- Q&A: Will the Roadmaster InvisiBrake Release Air Pressure Over Time When Disconnected from Motorhome
- Video: The Low-Down on the Adco Olefin HD RV Cover for Class A Motorhomes up to 43' Long
- Shop: Vehicle Tow Bar Wiring
- Shop: Vehicle Tow Bar Brake System
- Video: Checking Out the Roadmaster InvisiBrake Flat Tow Brake System
- Shop: Roadmaster InvisiBrake Flat Tow Brake System - Preset
- Shop: Adco SFS AquaShed RV Cover for Class C Motorhomes up to 23' Long - Gray
- Shop: Classic Accessories PolyPro III Deluxe RV Cover for Class C Motorhomes up to 32' Long - Gray
- Shop: Roadmaster Falcon 2 Tow Bar - RV Mount - 2" Hitch - 6,000 lbs
- Video: All You Need to Know About the Roadmaster Falcon 2 Tow Bar
- Video: How to Install: Roadmaster Falcon 2 Tow Bar on your 2022 Ford Maverick
- Q&A: Will Curt RVibrake Shadow 2 Fit 2026 Ford Maverick Hybrid
- Article: Best Vehicles to Flat Tow Behind an RV
- Q&A: Does Roadmaster Invisi Brake RM-8700 Come With Everything Needed to Install
- Article: Flat Towing Package for 2007-2018 JK Jeep Wrangler and Wrangler Unlimited
- Q&A: Blue Ox Flat Tow Setup for 2026 Ford Maverick Hybrid
- Q&A: Recommended Flat Tow Setup For 2022 Ford Escape Plug-In Hybrid Using Blue Ox Tow Bar
- Article: Flat Towing Package for 2012-2014 Honda CR-V
- Q&A: Recommended Flat Towing Set Up for a 2026 Ford Maverick Hybrid
- Q&A: Best Flat Tow Setup for 2026 Jeep Wrangler
- Article: Must-Have Flat Towing Components
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Article: Trailer Wiring Diagrams
- Article: Flat Towing Package for 2020 Jeep Wrangler
Jerred H.
1/19/2026
Hey, how did things go after leaving the vacuum port open on your InvisiBrake system in the Maverick? Did everything work as expected once you finished the setup? Your update could make it easier for others moving their system to a newer vehicle.