Syncro pneumatics

Since I drive a VW Vanagon Syncro, one of the first applications for Redshiftt I focused on is adapting positive air pressure servos to replace the feeble and expensive vacuum-powered servos the factory used to operate the diff-locks and driveshaft decoupler. This is actually pretty simple, it only requires two inexpensive custom parts to be made to adapt a common air cylinder from the process controls industry.


Here’s my test installation on my Syncro transaxle (which is filthy from chronically leaky side-seals; I need to redi-sleeve both output flanges). Pic was taken before the air lines were inserted in the 1/4″ one-touch airline fittings, which are a joy to work with. I’ll actually be using a smaller diameter tube and fittings for the market versions, making routing lines a little easier.


I’ve been running this for about a year and a half, using 40psi air pressure provided by an electric on-board compressor, which I also switch on with one channel of the knob controller. These cylinders are designed for up to 100psi air pressure, but even at only 40psi the diff-lock actuation is just night-and-day better than the vacuum system ever provides, actuation happens on the first alignment opportunity, and when de-actuation is needed it comes off with just a lift on the gas pedal to relieve pressure on the meshing teeth. That’s the kind of action I wanted which was the impetus for developing Redshiftt in the first place, and it won’t lose efficacy at high elevations like the vac system does.

I should be able to offer this setup for no more or even a lower price than the cheapo plastic vacuum servos sell for, and it is far more rugged and serviceable. I’ve developed an accessory control box with electric solenoid valves to operate them, the solenoids will be controlled by the knob and/or app on the channels the user chooses.


  1. John Wimberley

    This sounds wonderful! I’ve often sweated blood during curvy transitions from low to high traction surfaces, when it’s necessary to get out of 4wd FAST! This will be a very useful upgrade to the Syncro. May I be your first customer?

    • Chris

      Hey John,
      It’s great you can appreciate what an off-road performance improvement this will offer, or even in mixed conditions on-road. If you off-road much, and I know you do a lot, you probably already have an onboard air system of some kind, so why not give it more uses and get a step up in traction control? Plus the Redshiftt system will let you have instant control of a bunch of other things, limited only by your imagination.
      Hopefully there will be some competition for that first purchaser spot, but no worries, I’m making enough parts for everyone!
      Thanks for stopping by,

  2. Kevin Guarnotta

    I’d love to see more! I just came across your site.


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