Do I need tools ?Will I use them ?

Just a little warning about self adjusting brakes: DO NOT TOUCH THEM WITH ANY TOOLS! All of the manufacturers advise that if the are not adjusting by themselves then there is a problem that needs to be located and dealt with! About the only time a shop manually adjusts them is #1 when replaced and it's the first adjustment and #2 after a repair.

Also you are NOT a mechanic so you do not need to be messing around with them because if you screw up, then after the accident you're about to have all the lawyers that come out of the wood work will be all over the post accident reports and BRAKES is in the top 5 things checked and when they find a bad manual adjustment then someone is in deep sheep dip! Also, here are several different ways to adjust self adjusting brakes.The best is let the shop do anything related to self adjusting brakes!I can't stress this any more!

Manual brakes. #1 are on the way out! They are old technology. If you are taught how to adjust them it's ok but not in front of a DOT or after a DOT inspection unless you own the truck and trailer. You have to call a mechanic now a days!

Auto slack adjusters are adjusted from INSIDE the tractor sitting in the drivers seat! The easiest job you have on the truck related to a PTI!

It's simple and NO it will NOT wear out your brakes as some O/O's think or L/P drivers are led to believe. I'll explain during the lesson!

Release the brakes while at the fuel island or in the parking lot but I'd be sure you're not going to pissoff a sleeping driver when you do this! You can also do this while sitting at a red light!

Let the truck roll forward a little and then put at least 30 pounds of pressure on the brakes and release and do this a few times. If at the fuel island or in the parking lot put it in reverse and do this again. Roll and apply the brakes and you'll feel them go into adjustment. They just start to brake faster and you'll feel it. AND because you are not creating heat you are not wearing them out! Doing this several times a day while doing city driving keeps them in adjustment and if doing a lot of mountain driving also. You can do this when you have to stop at a brake check area in mountains or on the shoulder if you feel like your brakes are fading.

You will also be doing two PTI checks at the same time while adjusting the brakes! You'll be doing the low pressure warning and the emergency brake check.

One thing a lot of drivers do not know what to do is check the travel on the slack adjusters! There are several tools to use, one is a tool that you slip onto the adjuster and it allows you to manually move the adjuster so you can measure the travel on the rod. The other is a set of yellow plastic washers that you put on the rod then go up and apply and release the brakes and then go back and measure the travel.
You can also tell how the adjustment is by looking at the space between the brake shoe and the drum. You'll learn what it "looks like" after a brake adjustment.

Then there is the two person method. One person sits in the drivers seat and the other is under the trailer or tractor with a tape measure. (I keep a 25' retractable Stanley in my tool box along with a 100' measure too). Put the tape over the slack adjuster and the brake rod. Yell brakes and then look at the amount of travel and there you have it. Anything over 1" and they are "out of adjustment" Do this for each brake or, as in all 10 of them! This is what DOT does when he pulls you in. Best alternative to this is get the washer thing!

 

Good words of wisdom gentlemen Thank you!

 

Does the truck have to roll to do this?

What I mean is that I was taught that when you are sitting still doing your PTI and pump down the brakes to set off the buzzer and eventually pop the spring brakes, this will adjust your brakes (nothing said about the truck needing to move). But, I've recently had a few different mechanics and/or instructors tell me that this does nothing to adjust them. Haven't had issues with brake adjustment since I made this part of my PTI, so I'm assuming it's working.

As a side note, I recently took a very odd driving test for a job I was trying to get. Tester marked me down a few points for doing this on the basis that it was going to now take time for air pressure to build back up. Never crossed my mind, as this is always the time that I do my paperwork so the time factor is irrelevant, and it's kinda wrong to have a company be against me doing anything to test for safety.

 

have you ever heard the saying it's better to have them and not need them than need them and not have them I had a driver call a service guy ot at 2am to tighten batter cables don't do that to your company

 

While we're on the subject of self adjusting brakes....... I was talking to our shop forman a couple of days ago and he's gonna have this little item about brakes in our next safety bulletin.

It seems that we recently had a driver smoke a new set of brakes on a grade. When he got to the bottom he set all of the brakes and waited for everything to cool down.

When he went to move the truck after a while, the brakes wouldn't release.

Why?

Because the automatic adjusters had adjusted the brake shoes out while the driver was applying heavy pressure to them on the grade. The heat made the drums expand slightly and the brakes were now "adjusted" to the new oversize drums.

When the drums cooled they tried to contract back to their original size and "presto", instant brake lock-up with the shoes jammed against the drums and a call to the shop to get him going again.

For me it was one of those "forehead slapping Duh!" moments..... I had never really though about it ('cause I try like heck to never abuse the brakes) but it makes sense.

just sayin'


.............. Jim

 

What are batter cables? I've never heard that term before.

Never mind!!! I just realized it was a typo!!!! Oh dopey me!!!

 

I hope this gets out to all drivers. There's been lots of studies done about adjusting ASA and the results were simple. If you adjust them manuelly they will not stay adjusted. I believe the last study was done by the NTSB but if you do not want to believe any of us please look up the slack adjuster on the net and it will tell you there to have them in the shop if they are out of adjustment. I wonder how many schools teach this???

 

Good right up! I've helped a lot of drivers, because I know how much is sucks to have a break down, and I'm always surprised how un-prepared some drivers are. I helped one guy who didn't even have a flashlight. I keep a toolbox that fits in any sleeper-side box and it has a couple dozen metric/standard wrenches, a big channel lock, cresent wrench, multiple screwdrivers, torque bits, allen wrenches, multi-meter, mics screws, bolts, washers, hammer, wire snips, needle nose, tape, zip ties, extra flashlight, tape measure, jumper cables, extra lights, and a few other misc things. Granted I normaly only remember the times when I don't have the right tool, but if I really think about it, that little toolbox has saved me dozens of times and therefore has paid for itself dozens of times over just in downtime, let alone mechanics bills. I've always tried to do the basic maintenance and repairs whenever I couldn't get to a shop or terminal. Having said that, you have to know when to ask for help, or accept defeat so you don't make a bad situation, worse.