I just got the Ramps this week and used them for the first time TODAY on my 2003 Chevy Silverado Extended Cab with a 5.3.  It actually has a 2/4 Drop and 20" Wheels with 275/45R20 Tires.  I was on my Asphalt Driveway,  I put the Ramps right it front of my front tires, Get into my truck, and drove right up them!!! Didn't slip AT ALL.  There is a Rubber Pad in the middle Front, pretty thick, not large,  but it seemed to work for me.  I used to be a Professional Mechanic 3 months ago, and always had access to Racks.  I Changed Occupations for the better, and so I no longer have Rack access.  So I got a set of these.Again my truck is lowered, and so I was worried about a ramp not fitting under the front of my truck to drive up.  I had no problem with these like I said.  I put them right up Against the tire, and then drove right on up!!!  The Negative is it's not UP very high, at least on my lowered truck.  On my Low to the ground creeper, I could just get under to change the oil and oil filter.  I wanted to change the Fuel filter also, but that was ALMOST impossible.  It's along the frame railing back a bit near the front of the Gas tank,  I could barley get back enough to just reach the filter and 2 wrench it with one hand to get the filter off.  I did manage though.  I wish I could of do it on a rack at my old Job, but my old Boss is P.Oed that I left.  Now he has to work far more and hired a couple Idiots to take my place.  I wouldn't get my car worked on there now!!!I'm not going to knock it down any stars because it didn't lift my truck up enough as I knew how much it would raise it before I ordered them.  Again, No slipping for my truck and it's Rear Wheel Drive!!!  It didn't Sink in the Asphalt, or Crack, or anything else.  Nice and Solid.  The Price was right as $48, with no tax and free 2nd day shipping for me.  It's harder for me to do oil changes these days, having to do it at home, but then again, I've seen some of the work so called Pro Mechanics do on peoples cars/trucks from different places, and I think I'll stick doing most ALL that I can, other then things that just isn't feasible for me to do at home.  Things like Smog Check.