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07-04-2015, 08:48 AM
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#1
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Senior Member
Join Date: Sep 2014
Posts: 205
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Leveling - tires off ground?
I understand it's not a good idea to have the tires off the ground/blocks once the hacks have leveled. Is this true? Seems to me even if one works to put enough blocks under the tires to keep them in contact, there is still little load from the coach on them. What's the best practice? I read concerns on jack failures which causes major subsequent damage. But on my Newmar the jack is certainly well bolted to the frame.
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07-04-2015, 08:53 AM
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#2
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Senior Member
Join Date: Jul 2014
Posts: 35,349
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If it concerned me, I would jack it up a bit higher, slide some blocks under the wheels, and let it back down. Just remember to do the reverse, before driving off the blocks.
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07-04-2015, 08:56 AM
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#3
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Senior Member
Workhorse Chassis Owner
Join Date: Apr 2009
Posts: 904
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Jacks are designed & manufactured to LEVEL, not LIFT.
Jim & Shirley & Abbie (Scottie)
2013 Newmar Canyon Star 3911
2005 Dodge Grand Caravan
🎓 I always think I know more than I actually do! I'm not a 🚀 scientist, but I did stay in a Holiday Inn Express last night. 🏩
__________________
Jim & Shirley & Abbie (Scottish Terrier)
2013 Newmar Canyon Star 3911, 2005 Dodge Grand Caravan - Braun Accessibility Modified Toad, Remco Lube Pump, 5 Star Tune, Progressive Industries EMS-HW50C, Coach Net Emergency Road Service, FMCA 378968
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07-04-2015, 08:57 AM
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#4
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Senior Member
Join Date: Jun 2010
Location: Anacortes, WA (Stick & Brick)
Posts: 2,643
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There are two problems with wheels off the ground.
The dangerous one is that the parking brake isn't effective. The lesser one is that you need a ladder to reach to bottom step of the entry. There was only one place we stayed regularly, a family member's driveway, where the grade resulted in the front wheels being off the ground.
I would personally never raise the wheels off the ground that contain the parking brake.
__________________
Frank Damp -Anacortes, WA,(DW- Eileen)
ex-pat Brits (1968) and ex-RVers.
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07-04-2015, 09:05 AM
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#5
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Senior Member
Newmar Owners Club
Join Date: Jul 2006
Location: Wellington, Florida
Posts: 13,599
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Hi aeroquality,
Front wheel(s) and overnight stay, don't worry about it. Long term stay, don't do it. Rear wheels should not be lifted off the ground.
__________________
Gary
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
The Avatar Is Many Times Around The USA
Nobody Knows Your Coach Like Somebody Who Owns One Just Like Yours
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07-04-2015, 09:06 AM
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#6
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Senior Member
Join Date: Sep 2014
Posts: 205
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Is the parking brake on the rear tires on the Ford gas chassis?
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07-04-2015, 09:12 AM
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#7
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Senior Member
Newmar Owners Club
Join Date: Jul 2006
Location: Wellington, Florida
Posts: 13,599
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Hi aeroquality,
The short answer is rear tires. It has always been this way. Cars are the same. The front tires are not directly connected to each other. The rear tires are connected to each other via the rear axle and gear box. One parking brake mechanism can make both rear wheels solidly locked. A parking brake mechanism for the front wheels would be many times more complex.
__________________
Gary
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
The Avatar Is Many Times Around The USA
Nobody Knows Your Coach Like Somebody Who Owns One Just Like Yours
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07-04-2015, 09:12 AM
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#8
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Senior Member
Newmar Owners Club
Join Date: Oct 2009
Posts: 10,309
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If blocking is needed to get level, the entrance step is way high off the ground, I ask for another site. Site's are to expensive today to have to deal with your tire's off the ground and needing additional steps to climb into your Coach. I have only had to do this 2 times, I just go to the office, explain what is going on , and ask if they would please come look at my problem, they chose to just have me move.
__________________
2012 Essex 4544 2011 Jeep JK, M&G Braking, 2014 MTI 27' Hog Hauler, Wireless brake control, 2006 Ultra & 1989 Springer, 2003 Harley-Davidson
FLHR Road King Anniversary
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07-04-2015, 09:13 AM
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#9
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Senior Member
Join Date: Jul 2014
Posts: 35,349
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Quote:
Originally Posted by frankdamp
There are two problems with wheels off the ground.
The dangerous one is that the parking brake isn't effective. The lesser one is that you need a ladder to reach to bottom step of the entry. There was only one place we stayed regularly, a family member's driveway, where the grade resulted in the front wheels being off the ground.
I would personally never raise the wheels off the ground that contain the parking brake.
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How effective are the brakes, with half the weight, off the tires. How much lift, before it becomes ineffective.
The feet of the 4 jacks are probably as many square inch's of contact as the 4 rear tires.
Cause for thought.
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07-04-2015, 09:23 AM
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#10
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Senior Member
Join Date: Nov 2005
Posts: 7,396
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Many good commens here--lack of a parking brake on back wheels is prehaps the most important for/against lifting the back axle. Since you are already on an angle, the extra twist on the jack pistons can not be good. While most jacks are probably rated to "lift" the axle in question--the problem is that many suspensions are of trailing arm design, so once off the ground, the entire weight of the axle is hanging from the shocks--not a good idea to me.....
__________________
Old Scout
2015 IH45 Foretravel
2003 Alpine 40' MDTS [Sold]
New Braunfels, Texas
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07-04-2015, 09:26 AM
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#11
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Senior Member
Newmar Owners Club
Join Date: Jul 2006
Location: Wellington, Florida
Posts: 13,599
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Hi twinboat,
My concern with the rear tires being off the ground is that the jacks are built to lift vertically. Horizontal movement is not their best design or practical use. Even a slightly bent jack piston (one might not be able to visually detect this) will provide difficulties and considerable irritation until diagnosed and replaced.
__________________
Gary
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
The Avatar Is Many Times Around The USA
Nobody Knows Your Coach Like Somebody Who Owns One Just Like Yours
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07-04-2015, 09:29 AM
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#12
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Senior Member
Newmar Owners Club Freightliner Owners Club Spartan Chassis
Join Date: Apr 2012
Location: ON THE ROAD...SOMEWHERE
Posts: 6,973
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I've read and heard lots of cussing and discussing this topic. I really think it "depends".
I'm willing to hear what others think but my opinion is this. In theory
1. If a coach is level on all 4 jacks there isn't any thing to make it want to move in any particular direction except straight down. That means the drive wheels that have the park brakes aren't doing that much if anything. About the only things that make it want to move would be wind, wild dance parties inside the coach and earth quakes.
2. Blocking wheels does little to nothing to protect the coach from a sudden failure of a jack or the whole system. That would be unless you block each wheel so that the wheels are nearly at the position they would be if you were driving the coach. Many times I've seen blocks under the front wheels that basically filled the dead air but provided nothing in terms of meaningful support.
3. IMHO (and sometimes ignorant) the only wheels that need to be blocked are the drive wheels provided you can get enough weight on them for the park brake to actually work. I once saw a coach with 2 layers of 2X8s under the drive wheels on both ends. I asked the owner if the layers were some how secured together and he said no. I really wonder if the friction between the board layers is enough to keep them from sliding between themselves, especially if there wasn't a lot of axle weight on them? I would assume that layered boards need to be some how connected.
So far I have never blocked the front wheels that have on a few occasions had one or both be off the ground. I've also not blocked drive wheels but in a couple cases have had one side off the ground with the other one firmly planted. I would also feel a little insecure if both ends of the drive axle were airborne. In such cases I sacrifice coach level to keep at least one end of the drive axle firmly planted.
BTW...as needed I block the jacks with up to 6 2X12X24 boards. I can normally put 1 or 2 under the rear jacks and 1 under the front jacks after I dump the bags. The reduces the amount of jack arm length used to level the coach and provides more stability. I normally only need 4 of them in some logical pattern to help in leveling.
Normally I don't use all 6 except in a couple cases. The first is when the ground (or asphalt) is soft to avoid the pads sinking into the ground. The second is when we will be parked for a couple weeks or more regardless of the surface. That helps the coach be more stable by reducing the jack length.
YMMV
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Don, Sandee & GSD Zeus. Guardian GSDs Gunny (7/11/15) & Thor (5/5/15)
2006 2015 DSDP 4320 4369, FL Chassis, 2013 CR-V 2020 Jeep Overland, Blue Ox Avail, SMI AF1.
[SIGPIC][/SIGPIC]
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07-04-2015, 09:37 AM
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#13
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Senior Member
Newmar Owners Club Freightliner Owners Club Spartan Chassis
Join Date: Apr 2012
Location: ON THE ROAD...SOMEWHERE
Posts: 6,973
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Quote:
Originally Posted by Jim T.
Jacks are designed & manufactured to LEVEL, not LIFT. ...
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But...they do LIFT. Keep in mind that unless you are on a perfectly level surface that the jacks LIFT the coach to being level. That means in many cases 3 of the 4 corners are not providing any support to the coach by holding any weight. In other words, 3 of the corner wheels are making contact but not bearing weight. The coach has been LIFTED off those 3 corners.
If all 4 axle ends are perfectly level and your coach's leveling system (manual or automatic) is properly calibrated then all jacks should stop before any serious lifting is done. That is the only time they don't perform any true lifting...in theory. LOL
At least that is how I see it.
__________________
Don, Sandee & GSD Zeus. Guardian GSDs Gunny (7/11/15) & Thor (5/5/15)
2006 2015 DSDP 4320 4369, FL Chassis, 2013 CR-V 2020 Jeep Overland, Blue Ox Avail, SMI AF1.
[SIGPIC][/SIGPIC]
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07-04-2015, 10:00 AM
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#14
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Senior Member
Join Date: Sep 2014
Posts: 205
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All great observations. If tires and jacks are all in ground contact that's 8+ points depending on number of rear tires. Certainly all will have some amount of weight force in each. Seems important to me to have the rear axle and tires in ground contact with a good amount of weight. That would mean putting the rear end up-hill of any slope. Couple that with a tire stop to prevent rolling. I agree on front tires on the downward end of a slope - the jacks carry most of the force and blocks could be adding little other than taking load off the suspension in holding the axle weight? Should one block the tires from rolling before or after jacking? I also notice slight shifts in tire position after jacking..
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