Hi coolmom42,
Every once in a while, your original question is asked.....Can you drive your rear tires on one ramp, such that one of the two tires is suspended in the air?
We have a smaller class-C motor home. You can see it by
CLICKING HERE. The weight on our rear tires is not as much as with bigger and longer rigs. I am comfortable using one ramp per rear corner, suspending the inside rear tire in the air. My decision was based in-part on a phone call I made to the Michelin tire company.
At home we have rain gutters instead of curbs. My question was, "Is it okay to park so the outer tire is suspended over the rain gutter to avoid the rig parked out into the road? He said it was fine. I then asked about driving the rig on ramps. He said to use two ramps. Then I asked him what is the difference between my first question and second question. He admitted there is no difference, but that is what they are required to tell their customers.
I use Lynx levelers. They resemble Lego blocks as shown below. Each block is one inch tall. They offer blocks, flat top caps, and wheel chocks. When used in combination, it becomes a fairly decent ramp. They store in nice compact zippered bags and are very light weight.
I searched the web and found this picture of all 3 different Lynx components in use at the same time, but only one block high. You can stack this higher and higher. The official limit is 5 blocks, 5" high plus the top cap.
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There are other products that accomplish the same thing. By chance I went with the Lynx product line. I am not saying it's the only good choice.