Community Forums

jimbo2013 · 09-24-2014, 03:47 AM

Bought this with 32,000 so only know what I learned since driving this year about 9,000 miles, I now have 41,000 miles on my Freightliner coach drums all round, fronts have auto slack adjusters, rear do not.

Stopped at a shop that had a certified dot guy take a look, said the pads are like new thickness wise, I saw that myself.

He made a minor adjustment on the rears said all looked good.

Just don't feel like I can stop on a dime.

any suggestions on what to check?

I was thinking about pulling the front drums for starters to see if there's anything noticeable there.

i

ElvistheKing · 09-24-2014, 03:55 AM

In theory if you stand on the brakes all 4 wheels should lock up (only try this somewhere with plenty of space!!) and/or ABS kick in if fitted. Of course that isn't to nice on the fixtures, fittings and contents.

Is there not a testing station that has a rolling road/brake tester.

OLYLEN · 09-24-2014, 07:09 AM

Like most of the RVers we are too EZ on the brakes. We don't use them hard enough. The cure, burnish the brakes. everything down,then on a boat so busy road use the brakes very hard from a higher speed several times and the brakes should improve. Now loaded your at 30000# plus or minus your not going to stop on a dime.

LEN

Rvbuzz · 09-24-2014, 10:42 AM

I was told but never confirmed that there are multiple compounds available for air barkes as well as hydraulic.
Check to see if you have a relining company anywhere near you.
I would attempt to try the prescribe procedure above first. Brakes have an optimum temprature they like to operate at. Get them good and hot with multiple near stops from 30-40 mph in a safe location.

dennis45 · 09-24-2014, 11:04 AM

Here is some interesting Bedtime Reading on this subject in relation to drum brakes with S Cams.

http://www.apta.com/resources/standa...-RP-005-10.pdf

Take note of Burnishing Brakes in 3.2.4.

jimbo2013 · 09-24-2014, 11:40 AM

that's great resource, tks

Quote:

Originally Posted by dennis45

Here is some interesting Bedtime Reading on this subject in relation to drum brakes with S Cams.

http://www.apta.com/resources/standa...-RP-005-10.pdf

Take note of Burnishing Brakes in 3.2.4.

D Lindy · 09-24-2014, 01:06 PM

Don't forget you're not stopping your car, you're stopping upwards of 15 tons, and that won't stop on a "dime", you'll need $10's to stop that.

TeJay · 09-24-2014, 02:28 PM

Google "burnishing brakes" You will find absolutely nothing about applying the brakes hard. Also once the brakes are properly burnished it will not need to be done again. However you can't burnish brakes that have been glazed by overheating.

I'm not as familiar with air brakes but I don't believe that drum brakes will lock up unless you are on gravel. Disc brakes can unless you have ABS. Since you don't know the service history or the care given the unit since you are not comfortable with the stopping perhaps they need to be looked at by a reputable facility. Glazed or overheated brakes can not generate the necessary heat to stop a coach. The only fix is to start over with quality shoes (pads are only used on disc brakes) machined drums and perform a proper burnish following the work.

If performed correctly you will have the best brakes available with drums brakes.

TeJay

ElvistheKing · 09-24-2014, 02:45 PM

You can lock drum brakes, just not sure you could on a truck! Certainly all the *cars* i've driven with all drums you could lock up so it's nothing to do with the basic way the brakes work.
Disk Brakes are better at dissipating heat than drums is all.

hartb1999 · 09-24-2014, 10:37 PM

are the brakes abs if so wwont lock up also follow proceedure for self adjusters if you have them

deandec · 09-25-2014, 10:45 AM

Quote:

Originally Posted by jimbo2013

Bought this with 32,000 so only know what I learned since driving this year about 9,000 miles, I now have 41,000 miles on my Freightliner coach drums all round, fronts have auto slack adjusters, rear do not.

Stopped at a shop that had a certified dot guy take a look, said the pads are like new thickness wise, I saw that myself.

He made a minor adjustment on the rears said all looked good.

Just don't feel like I can stop on a dime.

any suggestions on what to check?

I was thinking about pulling the front drums for starters to see if there's anything noticeable there.

i

Do you do the DOT recommended Pre-Trip Air Brake Test on your rig?

Part of that procedure adjusts the automatic Slack Adjusters and might improve your brake performance.

If needed, the procedures are easily found on the web.

Jimalberta · 09-25-2014, 04:52 PM

My DP didnt stop as quick as I thought it should so I did the adjustment thing with them and now it stops much better.

To adjust the automatic slack adjusters you need to get the engine running and have full air pressure, put transmission in neutral, release the ebrake air ( push the yellow button in ) then step on the brakes hard and release, do this 6 times . This will bring your adjusters up to the top. After I did this I noticed a significant improvement in braking.

Cheers