If you have a 0 to 3/4 gravel pile (I do), I make ramps out of that. If you put in some stakes and side boards , they don't have to be too wide, but if you don't then you will want to make the ramp at least twice as wide as your tractor to prevent sliding off of the sides. But the dirt will work too, or logs and dirt. I would rather use a dirt or gravel ramp than the car ramps anyway.. easier to hit with worrying about falling off. Just start stacking dirt of gravel right up against the dumpster, make it as wide and as high as you need. Dont forget to slightly dump your bucket as you start to go up the ramp to prevent materiel from spilling back out on to your hood. Just go slow and use 4wd and use common sense.