Getting your haldex slack adjuster installation done correctly is one of those jobs that keeps your own rig safe plus your brakes biting on exactly when they will should. It isn't particularly difficult as soon as you know the rhythm, but a person definitely don't need to wing this when it comes to stopping strength. If you've noticed your brake action getting a small long or you're just doing some preventative maintenance, replacing out a slack adjuster is a solid afternoon task that takes care of within peace of brain.
Before you even touch the wrench, let's talk about safety. You're working under a heavy vehicle, and you'll be messing with the air program. Make certain those tires are chocked—not simply one, but each sides. You'll need to release the parking brakes to find the slack adjuster away, and if you haven't secured the particular truck, it's going to roll. Nobody wants a "runaway truck" story to tell at the diner.
Collecting the Right Tools
You won't require a whole rolling tool kit with this, but getting the right stuff on hand makes the haldex slack adjuster installation proceed much smoother. You'll definitely want a 7/16-inch wrench or even socket—that's the standard size for the modification nut on most Haldex units.
Grab a set of pliers for those persistent cotter pins, the hammer (the common "persuader"), and probably a pry club if things are a bit rusty. A good shot of penetrating oil a few minutes before you start may also save you a lot associated with frustration. Oh, and don't forget the grease gun. Brand new adjusters need a bit of love perfect out of the particular box to ensure they will live an extended, joyful life.
Obtaining the Old Hardware Out of the Way
Prior to the new part continues on, the old 1 has to visit. Begin by backing from the adjustment nut. You'll hear a distinctive clicking sound—that's the particular internal ratchet carrying out its thing. Maintain turning until there's enough slack within the system to pull the pins.
Once the tension is off, remove the cotter pins and the large clevis pins that connect the adjuster to the brake holding chamber pushrod. If they're seized, provide them with a tap together with your sludge hammer. With the pins out, you may slide the outdated slack adjuster right off the S-cam spline. If it's stuck on the shaft, a small more penetrating essential oil and a mild pry should perform the trick. Have a second to wipe the S-cam splines; you want the new someone to slip on without combating a decade's well worth of road dirt.
Preparing for the New Installation
Now we're in the middle of the haldex slack adjuster installation . Period new Haldex unit and provide it a quick appearance. Most of these are "Self-Adjusting, " meaning they possess a control hand that tells the mechanism when in order to tighten up. This particular arm is the most important section of the setup.
Before you slide it on, check the S-cam for almost any side-to-side play. When the bushings are usually shot, a new slack adjuster won't fix your braking system issues for lengthy. If everything seems tight and clean, apply a light layer of anti-seize or grease to the splines. It makes items easier now and far easier five years from now once the next guy (who might be you) has to take this off.
Placing the New Adjuster for the Shaft
Slide the fresh Haldex slack adjuster onto the S-cam. You want to position it therefore the body of the adjuster will be pointing toward the brake chamber. This is how the control arm comes into play. On a Haldex setup, that handle arm needs in order to be anchored in order to a specific bracket on the axle or the brake step itself.
In case your kit came with a design template or a specific bracket, follow individuals instructions closely. The angle of the control arm will be what determines the brake stroke. In the event that it's off by even a few degrees, the adjuster won't know whenever to click, plus you'll end up with brakes that are either too loose or dragging. Arrange the holes within the slack adjuster using the clevis on the particular pushrod. If they will don't fall into line flawlessly, you can draw the pushrod out a bit or rotate the adjusting nut on the slack adjuster in order to move the arm into place.
Connecting the Pushrod and Control Supply
Once every thing is lined up, slide your clevis pins back within. It's always the good idea in order to use new cotter pins rather than trying to straighten away the old, rusty ones. They're cheap, and they're what keep your brakes through falling apart upon the highway.
Now, let's discuss that handle arm again. Many Haldex units possess a "pointer" or even a specific notch that tells a person if it's set up at the right angle. Make sure the control left arm is secured tightly to its mounting bracket. If this wiggles or changes, the "automatic" component of your automated slack adjuster isn't going to function. It's the "brain" of the unit, therefore address it with respect.
The Initial Adjustment
Even though it's an automatic adjuster, you still have to do a guide setup during the haldex slack adjuster installation . You can't just slap it on and generate away. Use your own 7/16-inch wrench in order to turn the modification nut clockwise until the brake shoes are tight against the drum. You'll have the resistance get pretty heavy.
When the shoes are touching the drum, back the nut away from about a half-turn (usually about two or three "clicks"). You're looking regarding a specific clearance—typically around. 015 in order to. 020 inches in the event that you're utilizing a feeler gauge, however the "half-turn back" rule will be the common industry method. Spin the particular drum or the wheel if it's still on. It should spin openly without any dragging sounds. If a person hear a constant "shhh" sound, you might have it a tad too tight.
Testing Your Function
Don't simply take my word for it—test the particular stroke. With the air system pressurized to at least 90-100 psi, have got someone apply the brakes as you calculate how far the pushrod moves. For the standard Type 30 chamber, you're searching for a stroke of lower than two inches.
If the particular stroke is within limits, you're fantastic. If it's too long, double-check that will control arm mounting. If the left arm isn't held fixed, the interior gears won't use take upward the slack as the pads wear out. This is the most common mistake people make during a haldex slack adjuster installation , so it's worth a second look.
Last Greasing and Upkeep
Now that will it's installed and tested, grab that will grease gun. Pump grease to the fitted until you observe fresh grease getting rid of out of the relief hole or even around the camera splines. This maintains moisture and sodium out of the particular internal gears. Haldex units are quite tough, however they don't like running dried out.
Moving forward, these things are mainly "set it and forget it, " but you should nevertheless look into the stroke during every pre-trip inspection or oil modification. If you find yourself having to manually adjust an automatic slack adjuster every week, something is wrong. Usually, it's a sign that will the internal clutch is slipping or the control arm comes loose. Manual realignment should be a temporary fix, not really a routine.
Why Quality Issues
It may be tempting in order to grab the least expensive generic part a person find online, but sticking with a genuine Haldex unit makes a difference. The internal clearance sensing technology these people use is top-notch. It's designed to react to the real gap between the particular lining and the drum, rather than precisely how far the pushrod moves. This qualified prospects to a lot more constant braking across all your wheels, which is exactly what you want when you're hauling a full fill down a large grade.
Getting the time in order to do an appropriate haldex slack adjuster installation ensures your truck stays up to date with DOT regulations and, moreover, remains safe on the highway. It's a rewarding DIY job for any owner-operator or fleet mechanic who appreciates a job properly done. Simply take this slow, watch your own finger placement near the pushrod, plus always double-check your measurements. Happy aching!