Know it may be stupid to ask, but remember I had an 85 FTL with manual slack adjusters, and was wondering do you and if so how to adjust the auto slack adjusters?

Thanks.

 

you relly shouldnt have to unless you replace the brakes or work on them or a slack adjuster goes bad.i like to set mine up abought every 6 monthsto be safe but there always very close to where they need to be.hauling 50 to 60 ton in a three axle dump with this truck.anyways set them as anything else all the way tight then back off a half turn is how i do mine.

 

There are different types.

If you do what the above poster recommended, you will destroy meritor slacks.

They need to have the adjusting pawl removed first(3/4" wrench). Then like the above poster said, bottom out, back off half turn.

The half turn should not be relied on either, the absolute final say in this process is the brake throw.

The other type I know of has an internal clutch. I do not recommend bottoming these out, as slipping backwards on the clutch wears it out.

 

thanks for correcting me on the pawl with the 3/4 wrench allen i forgot to put that on there.phill

 

Automatic slack adjusters, if they are working correctly, should not need manual adjustment. And during a Full Level 1 inspection, if a inspector sees wrench marks on these, they will ask for the repair sheet where a certified mechanic worked on them.

Automatic slack adjusters, again if working correctly, usually will adjust during a pump down test (you know, the one we all do every day ), by applying 40-50 pounds of pressure and holding for a couple of seconds, and then repeating a few times.
At least that is how the T-2000's, Pete 387 and 379's I have driven work. Never had to take a wrench to them, but again, these have all been very well maintained trucks, and if something does not look right, it is replaced.

This website has explains the methods, if you have replaced components on your brakes, basically what a previous poster had stated,

http://www.prairietruckandtractor.com/airbrakad.html

 

How do you fit 60 tons in a triaxle?

 

well they take a big end loader run it into the coal pile get a big bucket full and dump it in the trailar,then repeat till it is full ops: 38 foot rhodes trailer ive had as much as 65 70 ton on it [this is before the coal is cleaned and has a lot of rock in it]i can post scale tickets if need be obviously you have never hauled coal before.phill

 

On the Meritor slacks that our trucks have, you can stick a screwdriver under the little round button on the side of the slack and pry it outward to disengage the pawl and back off the adjustment without harming the slack adjuster.

When done, simply remove the screwdriver and let the button snap back in to resume normal operation.

I've found that 1/2 turn is too much. I back off 1/4 turn (90 degrees) and that usually results in about a 1" stroke when applied.

Haldex.

I agree that it is not recommended to repeatedly back those off manually, because of the wear on the teeth.

 

Meritor automatic slack adjuster:

http://www.meritorhvs.com/MeritorHVS...nts/SP0737.pdf

Note the "pull pawl" in the photo on page 2..

You pry that outward with a screwdriver to disengage the pawl while backing off the adjuster.

 

VERY CAREFULLY