According to the haynes manual the jacking points on my 2005 Corsa are on the sill whether its with the scissor jack or with a Trolley jack. It mentions using a block of wood with a groove cut in it to accomodate the sill.
The jack I currently have only has a very small cup (about 2") and I was thinking of treating myself to the following which has a much larger cup and could be used more safely with a block of wood/other to protect the sill;
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I have heard of people using Ice Hockey puck's with a groove cut in them as protection, there are also more expensive jacks(didnt really want to spend over 100) that have rubber pads already fitted in the cups.Just looking for a bit of input really.
Thanks