Do Flat Tow Supplemental Braking Systems Work without Vacuum Assist Brake Pedal

Updated 09/24/2025 | Published 09/10/2025

Question:

Im installing a ready brake surge brake on my 2017 Honda fit .When the engine is off the brake pedal loses vacuum and changes to a very hard pedal. I know this is normal but will this cause a issue with the cable or the vehicle brakes ? Ive researched this system and surprisingly Ive seen no mention of this.

asked by: Michael

Expert Reply:

Hey Michael, supplemental braking systems like the Ready Brake or the Blue Ox Patriot part # BLU37TR that we carry are designed with the fact that the vacuum brake system won't be energized and the brake pedal will be harder to press so you don't have anything to worry about. The mechanism that presses the brake will be able to press hard enough to overcome that.

expert reply by: Jameson C

Jameson

9/24/2025

Thank you for your reply I thought without vacuum it would be difficult for the brake system to function properly. I am towing a very light vehicle and the system is proportional so after checking with you I am confident It will work as described. Although I would be skeptical if I were towing a heavy vehicle like a Navigator, Escalade or a full size pickup I probably would then install some form of vacuum assist . Thanks again.

Jameson C.

9/24/2025

@Jameson Glad to help! Even if the vehicle was heavier you still wouldn't want to try and add in vacuum assist as the system can still work. On heavier vehicles the braking systems are proportionally more powerful so it's still about the same amount of pressure give or take to actually stop the vehicle.

Mike

9/24/2025

@JamesonC, I never took into account that larger heavier vehicles inherently have more powerful systems to begin with. So I see a full size vehicle in my future ?? Im sure I have more questions for etrailer. Thanks again.