Forum Discussion

JeffPritchard's avatar
Apr 28, 2013

Rancho "remote" adjust debug

My "new to me" F-350 Dually came to me with 4 Rancho 9000 shocks and an odd "remote" setup for controlling them.

I say odd, because it was some aftermarket (non-Rancho) digital controller plus a Firestone gauge/toggle switch arrangement.

When I got the truck, I quickly discovered that this system was broken. The shocks are as if they aren't even there (VERY bouncy spring-like ride). I can't get any pressure to come up in the Firestone gauge on either side (seems to have left and right controls and needles).

The "digital" controller was some 2-bit dinky company that I can't even find on the web. The only printing on the whole thing was "Digital". I googled til my fingers were numb and couldn't find anything that looked anything like this one. It didn't do anything but blink on and off when I got the truck. I decided I didn't want to try to figure it out. I took it out a few weeks ago because I kept hitting my knee on it. The "system" worked identically before and after removal of the "digital" POS.

Anyway, after a VERY bouncy maiden voyage with my TC on the truck this past week, I'm wanting to get the system working at least to some degree. My current living arrangement makes it very difficult to get under there and see what's up (busy street, steep/short driveway).

Here's what I can see easily:
1) all 4 rancho's look fine on the outside and they each have an intact small hose going to them.
2) when I run the toggle switches on the firestone gauge controller, I can hear the air pump humming. I don't hear any air coming out anywhere, but maybe the normal flow rate is too low to be able to hear that.
3) the gauge for the drivers side never budges when I hit its toggle. The one for the right side goes up just a tiny bit and no further, then drops back to zero when I let loose of the toggle switch.

So I find myself wondering two distinctly different things that perhaps somebody here can provide some insight on...
1) Is there a common failure mode for this kind of system that the above description fits well?
2) is there some really easy and quick "hack" I can do to get some shock action without getting the real problem solved yet?

On number 2 above, I was thinking maybe putting some sort of a "clamp" on each of the small hoses right near the shock would pressurize the shock in a way similar to what the manual knob would do on a non-remote system? I have no understanding of how this adjustment system works, so maybe this is just wishful thinking?

thanks!
  • When I solve something like this, I always try to come back to the thread and document my solution in case somebody else stumbles upon the thread.

    This turned out to be fairly simple. It turns out the shocks are adjustable via a small internal "piston". This piston is spring loaded, and is pushed in to increase the "stiffness" of the shock. With regular knob adjustment, the knob has a coarsely threaded "screw" attached to the knob. As it is turned clockwise toward 9, the screw pushes further against this small adjustment piston and stiffens the shock. For remote, the air pressure from the control line pushes in on that same piston. The more pressure in the line, the further in it pushes that piston, via air pressure.

    I decided to just make my own adjustment screw assembly. I took a thin piece of metal (cut from a nailing strip using a pair of tin-snips ). I drilled three holes, with the outer ones being exactly 1 inch apart (same as the mounting holes on the shock). I used a tap to thread the middle hole for an "adjustment screw".

    Seems to work great. Took me an hour or so to do all 4 of them.

  • JeffPritchard wrote:
    {

    Thanks!
    So is "clamped off" controller line effectively the same thing as having the control set to max?}



    That would depend on the amount of air pressure trapped and retained in the line thus clamped.

    Zero air pressure would be the least damped valving, similar to 0 or 1 on a turn dial. I don't know what pressure is required to be maintained in the valve cylinder to keep the valve piston contracted to simulate a maximum damping setting (5 or 9, depending on whether your shocks are 9000, versus 9000x or 9000XL).

    Tennaco has a free technical service 800 number you can call... something like 1-800-GoRancho or some such. You can also order a knob kit through them.
  • Keep it simple. Run the compressor and squirt Windex or soapy water on each shock where the hose attaches, you may not hear the air leak. Also look where the 4 hoses join. sometimes they get loose and leak air.
  • BigToe wrote:
    Suggestion: Post a wanted ad on craigs and other truck and rv forums requesting the take off manual knobs from Rancho 9000 owners who have added any type of in-cab controller (like "MyRide" etc)

    Then, with the manual knobs in hand, unscrew the two allen bolts at every shock, and install the manual knobs. When you disconnect the air lines at the shock body, any air pressure applied to the valving piston will be released to atmosphere, so you can set your knobs to the 12 noon position, fully retracted.

    Having converted the shocks back to manual control, you can

    1. Determine that the shock absorbers themselves actually dampen your spring bounce, and

    2. Determine the optimal normal setting for your shocks by experimentation.

    That having all been done, you can then see about your aftermarket air actuation system. I've had Rancho 9000 shocks for 12 years on my current tow vehicle, and after making occasional adjustments, I have not found that I necessarily "needed" an in cab control system, with all of it's vulnerabilities to failure.


    Thanks!
    So is "clamped off" controller line effectively the same thing as having the control set to max?
  • Suggestion: Post a wanted ad on craigs and other truck and rv forums requesting the take off manual knobs from Rancho 9000 owners who have added any type of in-cab controller (like "MyRide" etc)

    Then, with the manual knobs in hand, unscrew the two allen bolts at every shock, and install the manual knobs. When you disconnect the air lines at the shock body, any air pressure applied to the valving piston will be released to atmosphere, so you can set your knobs to the 12 noon position, fully retracted.

    Having converted the shocks back to manual control, you can

    1. Determine that the shock absorbers themselves actually dampen your spring bounce, and

    2. Determine the optimal normal setting for your shocks by experimentation.

    That having all been done, you can then see about your aftermarket air actuation system. I've had Rancho 9000 shocks for 12 years on my current tow vehicle, and after making occasional adjustments, I have not found that I necessarily "needed" an in cab control system, with all of it's vulnerabilities to failure.
  • Why don't you contact Rancho, you may be able to get a controller from them.