adjusting brakes

Ok so as stated above that needs to be threaded back in... Its not meant to be threaded out, but the center portion of it can be pryed out a little bit with a flat screw driver so you can adjust the slack adjuster.

 

So yes, you should have had the brakes release before you should have only had to pry out the “button” on that slack.

It looks like from the picture that the threads have broken off the part you actually tried to loosen. I don’t know if you can get a nut release “button” assembly for that slack or if you have to buy the whole slack.

So on the other slacks like this one.
Block wheels, Release the park brakes, adjust the top square bolt on top till tight. Use a screwdriver and pry out where I put the arrow. Should not come out more than 1/8”. Then back off the square head 1/4-1/2 turn.
You should be able to adjust them with a 5/16” wrench and a flat screwdriver, but they do have a special set of tools for just that type of slack.

 

Meritor slack adjuster pdf
https://www.google.com/url?sa=t&sou...FjAPegQIARAB&usg=AOvVaw3bljvR2Bx1-lgpLGjX-_mz

 

Slack Adjuster Tools
The 'prong' end will pop the center out of lock position. just like others have stated, you can also use a flathead screwdriver.
Google Image Result for https://www.anythingtruck.com/mm5/graphics/00000001/430-33200_800AT_540x540.jpg

 

Op
Since you mentioned that your new to working on trucks. If your adjusting brakes on your truck and the brake chamber pushrod starts to come out of the chamber your going the wrong way.