This is something every DIYer should be mindful of. Something you can do if you are taking the wheels off is place them under the car. If the car should fall, the wheel will keep the body from falling completely to the ground.

This is also why I like using quality ramps whenever I'm doing something that doesn't require removal of a wheel. The car is already at rest.

That's not to say you can't have an incident with ramps. At a VW get to gether once some friends and I were working on a noobie's new to him Jetta. A friend pulled the car up on some ramps to take a look at the turbo oil return, and parked the car in gear. We asked the owner to start the car, which he did, but then didn't notice the car was in gear, poped the clutch, and sent the ramps skidding out from under the tires. The car came almost straight down on my friend. Fortunately there were about 20 people standing around watching, and all of them immediately picked the car up and my friend got out from under it. He had some bruised ribs, but was otherwise ok. Scary stuff though!

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.