Gee, you guys are really safe.
I drive my 123 up on ramps to change the oil, and then jack up the rear and use some old jackstands I got for $5 (with the pin) and $10 (the ratcheting kind) in yardsales. I then have some 8X8X12 blocks of hardwood (oak, O think) to put under the rear as a backup. I do all this on cement. I agree that a jack can be unsafe when sitting on asphalt, as it will tend to sink into the goo, especially in the summer

My neighbor spent a couple of weeks out of work for trying to remove and replace a muffler with the car on a bumper jack. I think THAT would be dumb.

The ratcheting jack will not slip down while it has a load on it. You would need to clobber it with a sledge to get it to slip.

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Semibodacious Transmogrifications a Specialty

1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)

"Time flies like and arrow, yet fruit flies like a banana"
---Marx (Groucho)