Community Forums

Tom222 · 03-02-2014, 03:20 PM

Ok, my driveway is slightly downhill, just very slightly, maybe it drops 1 foot in 25 feet. Can I put the jacks down or does the location need to be level?
And do I need to put down blocks under the jacks, could it break the concrete?

Thanks

Tom

TdogKing · 03-02-2014, 03:34 PM

As long as your rear tires stay firmly on the ground with your emergency brake on you'll be ok. Cracking the concrete is a guessing game , not knowing it's condition, thickness , strength etc. if you choose to put a pad under it to distribute weight because you want to help the chances of not cracking the concrete it needs to be much bigger than the size of the pad on your jack. Hope this helps !

Budski · 03-02-2014, 03:47 PM

It's not a good idea to put your slides out if your not level. The uneven stresses on them can cause problems. Depending on your levelers if the grade is to step they will try but then stop an indicate a fault or one or more lights will not aluminate. Remember never pick your tires off the ground.
Dave

Ray,IN · 03-02-2014, 03:57 PM

1' in 25' = a 23 percent grade. (that's 23 percent of 45 degrees) I'd make sure all wheels are chocked to prevent the RV from sliding on the jacks. See: slopemeter.com and look for the conversion tables.

Tom222 · 03-02-2014, 04:57 PM

Quote:

Originally Posted by Ray,IN

1' in 25' = a 23 percent grade. (that's 23 percent of 45 degrees) I'd make sure all wheels are chocked to prevent the RV from sliding on the jacks. See: slopemeter.com and look for the conversion tables.

I looked at the driveway again, the portion closer to the garage is slightly steeper, but the rest of the driveway is almost level. As far as the strength of the driveway, it is a 4 inch wire reinforced driveway about 15 yrs old.

If the RV has auto leveling, will the wheels stay on the ground?

Tom

Dennis4809 · 03-02-2014, 05:15 PM

If your rv is 15', no problem. If it's 45' then the wheels would be well off the ground.

dabrooks · 03-02-2014, 05:22 PM

My sons driveway is not level and it drops about 8 inches from the front wheels to the back wheels. Since we can keep them in his garage we built some ramps out of 2x12s. We built them in steps using angle cuts. The top piece which is the smallest piece is 18 inches. If you use liquid nails and screws the boards won't split. They raise the front about 6 inches. Once you pull the front up on the ramps you can finish leveling with the jacks. Be sure to put the minimum of the same amount of boards under the jacks as the wheel nearest the jack has under it. That keeps the jacks from over extending. With the rear wheels still on the ground setting the parking brake secures the motorhome.

We have 4 sets of smaller ramps that we carry with us. Always remember that if you are pulling the rear up on ramps you need one under each rear tire. I almost always slide a board under the jacks to keep them from over extending even on fairly level ground.

1ciderdog · 03-02-2014, 05:31 PM

How long will the RV be up on jacks? If a day or so that's OK but if several days I'd try level it with blocks under the tires. On my motorhome - after a few days pressure - the jacks start to retract just a bit under the pressure. Easier in the long run to get it kind of level with blocks and then final adjustment with jacks. That's just my opinion.

"007" · 03-02-2014, 08:22 PM

Quote:

Originally Posted by 1ciderdog

How long will the RV be up on jacks? If a day or so that's OK but if several days I'd try level it with blocks under the tires. On my motorhome - after a few days pressure - the jacks start to retract just a bit under the pressure. Easier in the long run to get it kind of level with blocks and then final adjustment with jacks. That's just my opinion.

Always on unleveled ground level manually, if front wheels lift off pavement support wheels with blocks and never lift rear tires off the ground and chock the rear wheels.
AUTO level may twist the frame of coach and possibly pop your windshields out of their holding gasket on uneven or slope ground..

Alan_Hepburn · 03-02-2014, 09:06 PM

Quote:

Originally Posted by Ray,IN

1' in 25' = a 23 percent grade. (that's 23 percent of 45 degrees) I'd make sure all wheels are chocked to prevent the RV from sliding on the jacks. See: slopemeter.com and look for the conversion tables.

I think you're a bit off - 1' in 25' is the same as 4' in 100' which is a 4% grade, not a 23% grade. The equation for grade is 100*(rise/run) or 100*tan(angle of roadway).

Ray,IN · 03-02-2014, 10:18 PM

Quote:

Originally Posted by Alan_Hepburn

I think you're a bit off - 1' in 25' is the same as 4' in 100' which is a 4% grade, not a 23% grade. The equation for grade is 100*(rise/run) or 100*tan(angle of roadway).

Good catch Alan, thanks for correcting my foopa. Apparently I've forgotten all my trig., and of course makes my previous post completely wrong. 25/1, that should have lit my bulb.

Luckiest Dreamer · 03-03-2014, 07:49 AM

I don't know Trig from english, but I do know that my jacks have a shaft length that will adjust my coach about 13"'s to level it. any thing more and it just can't level it. That's when blocks are required!
I once backed a borrowed 20' trailer with some construction material on my driveway to unload it. Now my driveway has several cracks that were not there before.

98FPA · 03-03-2014, 08:44 AM

What concrete people will tell is that they can guarantee one thing: concrete will crack. My drive is at least 6" thick and it has cracked through the years. When it was new, I had front end loaders and tandem axle dump trucks on it without an incident. Most concrete driveways were probably formimg with 2x4" (3-1/2" thick) so there isn't anything unusual probably.

Blackcabby · 03-23-2014, 10:44 AM

Be real careful! In fact, I would definitely put out pads to distribute the load.

Depending on how old you driveway is, you can have erosion of the base (subsidence is what my CE buddies would call it). That basically means that there are parts of your pad that may be unsupported, or floating making it much more prone to cracking.

I had this happen with a two year old concrete driveway. Landscapers brought a bobcat down my driveway to access the back yard. In so doing, the bobcat cracked (more like collapsed) a section of the driveway. When we jacked the damaged concrete and prepared to repour, we observed that the gravel and soil base had settled significantly.