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Brakes and Leveling Quizzler
#1

Gang,

Please forgive me for the length of this post.  Skip to the bottom for the answer.

So you see what had happened waz......

I had a very strange thing happen to me today, and wanted to share in case someone else has the same situation.  I'm going to give you as much information as what I had, and then give you a chance to figure it out before I share with you what I *think* is going on.

My coach is 653 (2003).  It has disc brakes on drive axle.  As you know (or in case you don't) the emergency brakes work on the drive axle only.  They become active in the absence of air pressure....like when you pull the E-brake handle.  I had an issue with the e-brake valve and it was replaced at Newell last week.  I have new brakes all the way around and new wheel bearings all the way around.

Let's start at the beginning.  About three years ago I was in New Jersey with the coach.  I had parked at Cracker Barrel in a very non-flat parking lot.  I leveled the coach and spent the night, and in the morning after a hearty breakfast got on the road.  My coach goes into travel mode as soon as you release the air brake.  About 15 minutes later as I was driving on the interstate, I started smelling hot brake smell.  I pulled over and found that my passenger rotor was hot and that the brake was smoking.  I sat there for a while and applied and released the brake several times.  I decided that I would limp to the next exit.  Once I got there, the wheel was cooler and the brake was not smoking.  I promptly forgot all about this incident until today.

This morning I was parked at Cracker Barrel (note the coincidence).  Last night, I parked against a curb and put two slides out.  Since the coach was leaning a bit, I manually leveled to get the floor a little more level.  I spent the night and again ate a hearty breakfast.  I cranked the coach, put it in travel mode and waited for the coach to raise to normal travel height before I brought the slides in.  I took off and in about 15 minutes, I again smelled the brake smell.  I pulled over and again, the passenger drive brakes are super hot.  I called a fellow guru and we talked  through the issue.  After the brake cooled, I released the e-brake and put the coach in drive followed by reverse followed by drive followed by neutral.  At this point it was clear that the brake was not stuck.  So I got on road again.  A couple of more stops convinced me that I was ok to proceed.

I did notice that my gas mileage was a little low this morning, and I also thought I had a weird feel on the brake pedal before I smelled the brake smell.

Thirty minutes later I figured out what the problem was.  (I think).

Here is what it is not...
1)  I did not fail to release the emergency brake.  My disc brakes will NOT let me drive off while the brake is applied.
2)  It's not the bearings.  They are new and once the coach was happy, the wheels were cool even after running for hours.
3)  I had plenty of air pressure the entire time.  (Front, Rear and the other air gauge were in the normal range).

=====================Answer below======================

On my vintage coach, there is a known problem where the leveling system and the emergency brake don't get along.  So, as I am attempting to level my coach, I have to release the ebrake from time-to-time to allow enough slack in the suspension for the air-springs to do their thing.  I don't understand the exact cause, I suspect it is some geometry problem between the wheel, the brake, and the bags.

If I leave the coach in auto level the brakes will creak in the middle of the night as the coach attempts to re-level after air has leaked out of the system.

I think in both the trouble cases, I had leveled in somewhat abnormal conditions.  The coach had tried to auto level during the night both times.  So, when I cranked up and left, the brakes where in a bind in both cases.  Both times, I simply when into travel mode, released the brakes and drove forward.  I believe that the brakes never had a chance to fully release because of the binding issue.  Thus, even though the emergency brake handle was pushed in, it did not fully release the emergency brake.

The reason it has only happened a couple of times....

I have gotten to the point where I rarely leave the coach in auto level mode.  The brakes creaking in the middle of the night is worse that being slightly out of level.  I now normally just park the coach, turn off the key and live with the travel height.  Also, normally I need to back up and least once time before getting on the road.  I suspect applying the brakes in reverse releases the bind.  In both the cracker barrel times, I simply drove out of the spot and got on interstate.  

From now on, I will ensure that the e-brake is fully released by putting the coach in drive to get a little roll going, then neutral to remove forward propulsion.  If I stop, I know my brake did not release.  If I glide smoothly forward I know that my brakes are released and I can go on.  Alternatively, applying the brakes in reverse will probably accomplish the  same thing.

TL;DR  On 2002-2003 coaches the brakes and the leveling can interfere with each other.  This can result in the emergency brake being partially applied resulting in frayed nerves and brake smoke.

Bill Johnson
Birmingham, Alabama
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#2

bill, i am in the same boat. when leveling or even going to ride height i have to release the e brake to release the weirdness. the coach will really torque

tom

2002 45'8" Newell Coach 608  Series 60 DDEC4/Allison World 6 Speed HD4000MH

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#3

Never had the brake issue but mine would have a loud clunk in middle of the night as the suspension would settle. John Clark told me the issue was known by Newell and suggested once the coach auto-leveled to hold the brake pedal and release the e brake a time or two to let it settle.

Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
PO 1999 Foretravel 36'
1998 Newell 45' #486 

1993 Newell 39' #337 
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#4

It's not too hard to picture why it does that. The drive wheel is locked rotationally to the drive axle. Just for demo, draw an imaginary line up and down on the wheel. Now picture rotating the swing arm that connects the chassis to the axle as if the coach were moving up and down. The wheel, being locked to the axle, wants to rotate in alignment with the swing arm, but it can't cause the coach weight is holding the tire on the ground.

As Bill has pointed out with two data points on his coach, this situation can apparently bind the caliper pins, keeping the pads firm against the disc if the bind is not released.

I am thinking this is much more of a potential problem with coaches with rear disc brakes than drum brakes.

Richard and Rhonda Entrekin
99 Newell, 512
Maverick Hybrid Toad
Inverness, FL (when we're home Cool )
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#5

I have not had this problem with my drum brakes.

Chappell and Mary
2004 Foretravel 36 foot
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#6

If you wanted to level in these situations it would seem possible to loosely chock the front wheels and leave the e-brake off. That might work unless the e-brake is required for the leveling to work. It would be a hassle, but might help prevent falling out of bed at an inopportune time. Falling out of bed is always inopportune.

Jon Kabbe
1993 coach 337 with Civic towed
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