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Topic: Parking Brake? (Read 1122 times) previous topic - next topic

Parking Brake?

I just brought the new RV home tonight and it's parked out in front of the house on an incline. The incline isn't awful but it would definitely roll down the hill and do some major damage if the parking brake gave way. How does the parking brake work exactly?  Once the vehicle is off is there real risk of it letting go?  I don't really have any thing to put under the tires but if I need to I will. It'll be in storage by tomorrow afternoon.
Benjie, Ashley, Zoey, Fallon, and Lake
Round Rock, TX
In search of our next monster...

Re: Parking Brake?

Reply #1 –
The parking brakes are applied by spring brakes on the rear wheels, and they are activated either by low air pressure in the brake system or by pulling the parking brake knob which dumps the air pressure in the brake chambers. 

IF (IF!) your brakes are properly adjusted (the automatic slack adjusters have recently been "exercised"  by 5-6 full-on presses on the brake petal with full air pressure while stopped,) the parking brakes should hold pretty well on hills, but it's always advisable to chock the wheels on steep hills, especially since you may not know the current condition of the brakes on your new rig.
Dave and Nancy
1999/2013 U270 36' Xtreme
Motorcade # 16774
2013 Subaru Outback
KD0NIM

Re: Parking Brake?

Reply #2 –
A lot of companies and most all fire departments require their employees chock the wheels when ever they park the vehicle unless in the station. Buy 2 good sized rubber chocks, connect with a short piece of line and then place in front and behind your wheel anytime you park it unless in your flat garage. With two placed front and back, you can't drive off and forget them.

Worst case scenario (I have seen this happen): Coach or truck is parked overnight on an incline. Operator comes out in the morning and starts it. Tries to release brakes but air pressure is low and the coach won't move but he leaves parking brake button in the released position. He gets out with the engine running. Pressure builds until the parking brake releases automatically and the coach starts rolling until it hits something. 

Give an operator enough chances and he WILL get out of the cab forgetting to set the brakes. Think not? Thats how pilots make gear up landings. (a friend has made two)

I have seen several RV owners after stopping downhill, set the parking brake, put the transmission in reverse and quickly get out of the rig and chock the wheels. Won't hold well enough downhill.

Slack adjusters do get out of adjustment but they are not the silver bullet that will hold on much of a hill.

Expect a VERY leisurely stop if you ever apply the parking brake at any speed.

My service brakes work very well but when heading down my VERY STEEP driveway, I have to shift to neutral or it will continue to roll with the service brake pedal to the floor, first gear selected, 110 psi and the engine idling. Parking brake will not do anything here. I can lock up all six on the highway with max brake application so brakes do work well.  I have 350 HP but not enough to climb driveway, only able to back up (817 feet). 

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Parking Brake?

Reply #3 –
Benjie,

Here is a youtube video guaranteed to bring goose bumps on the back of your neck if you are a parking brake believer: Bus Parking Brake vs. Service Brake application  A 40 mph parking brake application took about 17 seconds to get an empty bus stopped.

Now imagine what going downhill after applying the parking brake would do to the stop watch.

We need a skull and crossbones smiley in the menu.

Pierce

Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Parking Brake?

Reply #4 –
As O/P have said, properly adjusted your parking brakes should hold your vehicle on fairly level ground. However they are only on your rear axle, and do not apply as much pressure as the service brakes do. I use wheel chocks on mine when parked on much of an incline. Also from you other post you have just had rear brakes on your new coach, it will take a few miles for the new pads and rotors to ware in and perform to their full potential.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Parking Brake?

Reply #5 –
Pierce,  In the trucking bidness my drivers always complained about tripping over the chock blocks and no amount of training seemed to get thru their thick skulls.  One of my favorite Safety Supervisor tricks was to walk the ready line and put chick blocks under any tractor that did not have them, you should have heard the comments.  The greatest was when the driver went to the shop and complained that the brakes were locked up.  The mechanics loved showing them what a chock block is.  I know, kind of a nasty trick but... whatever works. :) :)
Gary B

Re: Parking Brake?

Reply #6 –
I have been in the trucking business for 41 years... Brakes are similar.. Always chock wheels when on any incline. I chock mine incline or not... Easy insurance.
Dub McBride 1996 270

Re: Parking Brake?

Reply #8 –
Interesting video! It would be interesting to see a similar comparison done with a typical car. I'm guessing that the stop wouldn't be nearly as smooth.

Now, a question. Since I've never actually seen a Foretravel, where is the emergency brake knob located? DW and I have talked about what should be done if the driver is suddenly incapacitated by a stroke or heart attack. If the yellow knob is located in the center of the dash it would be much easier for the passenger to pull it than if it was under the driver's left elbow.

Re: Parking Brake?

Reply #9 –
I suspect that almost all of the FT's have the Parking brake knob left of the steering wheel, on the two Diesels I have had that is where they are.  Might make sense to put them in the center.
Gary B

Re: Parking Brake?

Reply #10 –
Forget putting it in the center, put a second knob where the passenger can give it a pull without removing the seatbelt.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Parking Brake?

Reply #11 –
Quote
Now, a question. Since I've never actually seen a Foretravel, where

David, You are more than welcome by me and probably everyone here to stop us and take a tour anytime.  Don't know where you are but I would suggest you look at the member map and if one of us is nearby drop us a PM and we will attempt to get together so you can see a real motorhome.
In our case we will be in FL for the next couple months.
Gary B

Re: Parking Brake?

Reply #12 –
A few years ago at the marina where I keep my boat we had a strong squall blow through.  Several of the hire sail boats on trailers took off across the apron, one hitting a woman who was not badly hurt.  You never know.  Chock them wheels.  I do.

Keith
Keith, Joyce & Smokey the Australian Cattle Dog
1995 U320 SE Extreme 40' WTBI Build # 4780, with a Honda CR-V hopefully still following behind.
Motorcade # 17030
FMCA # F422159

Re: Parking Brake?

Reply #13 –
 ;D
Quote from: Tom Lang –
Forget putting it in the center, put a second knob where the passenger can give it a pull without removing the seatbelt.

Tom,

Forget about putting a second knob over by the passenger. My wife would see a passing store with a sale sign in the window and it would become a push-pull contest. With it in the center, at least I would have a chance.  ;D

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Parking Brake?

Reply #14 –
Quote from: Pierce & Gaylie Stewart –
;D
Tom,

Forget about putting a second knob over by the passenger. My wife would see a passing store with a sale sign in the window and it would become a push-pull contest. With it in the center, at least I would have a chance.  ;D

Pierce
But honey, look at all the money I saved at that SALE.
The selected media item is not currently available.Bill&Doris 97 U270 36'
University of Parris Island Class of 66
Semper Fi  Build# 5174 MC#17094

Re: Parking Brake?

Reply #15 –
David,

We are traveling toward Smithville, MO, today. God willing, and continued good conditions, we will arrive there tomorrow afternoon. We will stay through Sunday, and then consider when to head farther north. If you would have any interest in seeing our 1997 U295, call me at 713-419-0313.

  Dave
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Parking Brake?

Reply #16 –
We bought two large-sized wheel chocks today at WalMart. The only chock that came with the RV was a small-size, single. I always chocked my airplanes and it makes complete sense to chock a motorhome.

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: Parking Brake?

Reply #17 –
Well, she held throughout the night, but I sprung for some chocks yesterday at Fleetpride!
Benjie, Ashley, Zoey, Fallon, and Lake
Round Rock, TX
In search of our next monster...