this 20 ton bottle jack? this air compressor?

I would avoid the $30 Chinese bottle-jacks, as reports of failures are semi-common. As it turns out, older Ford Superduty and current Ford Sprinter Vans come with either a Ford OEM YELLOW 4-Ton or RED 6-Ton bottle-jack, 2-stage. I went to my local Ford dealership and confirmed you can buy them new from Ford for about $200, and confirmed they were in the new Sprinter Vans on the lot. Many of these jacks end up in junk yards and on eBay for ~$50. I bought the RED 6-Ton, and the two stage action goes from a squat 8" to tall 18-1/2". Home Depot and others sell a BLUE "Ford" 6-Ton bottle-jack for ~$25, but I'm cynical it's actually a Ford OEM jack, and am certain it's quality is far less than the YELLOW and RED jacks. Search on eBay, and you'll see the YELLOW and RED jacks. I'm also keeping the simple screw jack in my F350. The screw jack might be able to support the weight of truck+camper on one wheel, but the issue is how physically demanding it will be to turn the crank when so much weight is present. For a given weight, the higher duty jack will be easier to crank/lever.

--SiletzSpey