Do I Need To Split Into The Vacuum Line On My 2021 Jeep 4xe To Install The Stay And Play?
Updated 09/12/2025 | Published 05/17/2025
Question:
For SM99251, I have a 2021 Jeef 4xe and I was watching the 2023 video and it kind of skims the part about the vacuum line. Since it is electric brakes do you just do the check value but not split into any vacuum line in the vehicle?
asked by: Jarod P
Expert Reply:
Hey Jarod,
You are spot on. Since your 2021 Jeep 4XE has the electric brakes you do not cut into the vacuum line or use it at all. What you will do during installation is simply reverse the vacuum connection at the operating unit. If you are like me and just said "huh?" I attached a photo for you to help show what I mean. The check valve on the operating unit you want to unplug with something like pliers, flip it and plug it back in so it cuts off the use of that check valve. You could also just cap it off if that is easier for you.
Do you have everything else for your flat tow set up? If not, let me know and I can help find the rest!
(click to enlarge)
Product Page this Question was Asked From
Demco Stay-IN-Play Duo Flat Tow Brake System for RVs w/ Hydraulic Brakes - Proportional
- Flat Tow Brake System
- Brake Systems
- Proportional System
- One-Time Setup
- Vehicle Battery
- Fixed System
- Power Assist Brake Compatible
- Hydraulic Brakes
- Indicator Lights
- Demco
more information >
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Nick S.
9/12/2025
Hey Jarod, Did reversing the vacuum connection on your Jeep 4XE work out for you? If you're still setting up your flat tow system and need more parts, I'm here to help!