How to manually adjust automatic slack adjusters?

Question

I want to adjust my auto slacks on my 06 Pete to make my brakes engage a bit sooner. I have tried releasing the brakes and putting a 7/16ths wrench on the adjusing s***w and tighted them tight and backed off about a half a turn, while it made that ratcheting sound, or stripping sound. I'm not sure if that is the correct way to do it. I'm used to manual slacks, so I'm not sure if I'm doing it right or not. Please help.

Answer 1

Hmm... The auto slacks should be keeping the adjustment correctly, your truck is too new to be worrying about that issue. So, here is what I have done. First, drop the trailer, do this while bobtail.

How is your trick driving?   :-)

Find a long driveway, get your truck in reverse and start backing up as fast as you can (in low range!) and jam the brakes hard. Do this a couple of times. You might get a click or two more out of them this way.

If you ever tried to back up your rig in high range, and got it to actually move well, you will know that at idle, in high range, you are moving at almost 20 mph. Be careful with that.

Other than that, I know what you are dealing with, it seems that the trailer is doing all the work. I don't know why some trucks feel this way and some don't. But I would trust the auto slacks to be doing their job right.

The hard and loud ratcheting sound when adjusting these kinds of slacks is normal. Some slacks have a "paw" you can pull out to relieve this, but I think those have pretty much been done away with.

Answer 2

You are doing it right ,I always snug my brakes tight and then back off 1/4 turn on trailers with auto slack adjusters and yes the adjuster rachets or makes noise like the adjuster is stripped.

my 94 pete( company truck) has manuals

Answer 3

Drop off vehicle at dealer.

Answer 4

I take it you are using the Gunite Slack Adjusters. First thing to do is chock the wheels and release the service brakes. Some slack adjusters have a pawl assembly. You take a tool and pry gently against the pawl assembly. Tighten the shoes against the drum and back off a quarter turn on the rear shoes. The Fronts I believe is about 1/2 turn. Remove the tool from the pawl assembly and hopefully it will seat back into the slack adjuster.