Installing SMI Stay-In-Play DUO on Vacuum Line for 2018 Jeep JL Wrangler
Published 09/12/2018 >
Question:
Ok, Ive got the Blue Ox base plate on, the brake light wiring kit is installed, the, Stay In Play and Controller mounted and wired. Getting ready to make the vacuum connection. The brake boost line looks way more complicated than an ordinary vacuum assist line. It is a hard plastic line, but has several connections making it difficult to find a place to splice in the check valves and connectors. My thought is to put them as close to the brake booster as I can. There is a short piece just outside the booster. See picture cutting where indicated in red. Do you think this would be appropriate? Or do you know of a better location? This 2.0 Turbo has not been out long so finding someone with install experience on this vehicle/engine combo has been difficult. Thanks for your help!
asked by: Stephen D
Expert Reply:
I spoke with my contact at SMI regarding the vacuum line on your 2018 Jeep JL Wrangler, as it is indeed bit different than previous model Wranglers. He said that when installing the vacuum portion of the Stay-IN-Play Braking System # SM99251 you will just cut the hard plastic 8mm line like normal and install the included 3/8 inch vacuum hose. They also recommend using a worm clamp for a more secure connection.
My contact sent along a few pictures from a JL Wrangler installation that they just recently performed. I have attached them to this page so you can use them for reference.

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
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