Safe to use JACK this way?

The load ranges tend to parallel the lift range. I'm using a 3 ton jack (Chinese made, bought on Boxing Day for $69). Got it for the extra lift range. I alternate between 3 and 6 ton jack stands, depending on how much lift I want.

Most every time I crawl under I push this section of tree trunk under first. It's a bit thicker than me

Oh, and a set of heavy rubber wheel chocks is good to have.

 

I disagree with the concept of buying the lowest rated jackstands that might hold the car up. If you look at this Craftsman website you will see that none of the jackstands are particularly expensive, so why would you buy the cheapest ones you can find, and decide that you cannot trust them enough to be under the car? Here is a pair of 4-ton rated jackstands for $25.
Sears.com

Ramps are fine if you are doing exhaust system work but are useless for many jobs where you have to remove a tire. Ramps are especially useless if your idea is to buy low-rise ramps that the Prius front end can climb over, since the vertical rise of the ramps obviously is limited.

Suppose you are working on removal of the engine or transaxle. This requires you to remove the front suspension and obviously the tires are coming off. Or, maybe you are doing brake or suspension work, or replacing a half shaft. For much of that work you need to get under the car and it has to be held up by a means that you can trust.

I have a pair of ramps which are too steep for the Prius to climb up; hence if I want to use them with the Prius I first have to jack up each side of the car, place lengths of 4x6 under the tires, then place the ramps between the wood and the tire. That reduces the vertical angle that the car has to ascend so that the body does not hit the ramp as the car moves up.

If you want to supplement the jackstands by using a tree trunk or some other such spacer, that is fine. I use a hydraulic floor jack on the side of the car that I plan to be on as my supplement.

Regarding the hydraulic floor jack, a 3-ton model is good for general purpose usage. If you look at the smaller capacity jacks you will see that the handle is relatively short while the lifting saddle is very small which makes the small jack useless for many tasks.

 

As you say, ramps are limited for Prius work, but if I already had them it seems they could be useful instead of a tree trunk; and then perhaps driving *off* instead of lifting the car up again to remove the jack stands. Or would the front end of the Prius get in the way ?

 

Yes, when I use the ramps along with the 4x6 wood, then I will first drive off the ramps, then drive off the wood.

 

There is a reason why those scissor jacks are known as "widow makers"

I think that they are awful, so much so I carry a small 2 ton trolley jack on boot of my car, have done for years. Much quicker and safer