I always jack up my CDTi with a trolly jack under the plastic jacking pads. The problem is that the jack has a dished circular jacking 'cup', with four lugs projecting from the top. When jacking the car up, there is a slight movement between jack and car; not enough to slip off, but the pad/cap is then not centered properly.
I have seen a modification on the web, whereby a spigot was welded to the cup. I have also made up a hardwood disc, which sits in the cup and has a projection on the top side, similar to the wheel changing jack in the boot, but it is not very successful.
My theory is to purchase a hard rubber ball, about the size of a tennis ball, cut it roughly in half, so that the rounded side will fit in the cup and the flat, cut side, will sit proud of the top of the cup. Then, when the jack is raised, the jacking pad will sink into the rubber, which will then keep the jack in the central position, as the rubber in the cup will stop the half-ball jumping out of the cup and the ribs on the plastic jacking pad will grip the top side of the rubber ball.
Do other members think this will work, or do they have there own ideas?
Ideally, a fully moulded hard rubber adapter, that can be fixed to the jack lifting cup, would be the answer. Does any member have the facility to produce such an item?
Also, has any member any experience of using the CJ adjustable car ramps (one manual type & one hydraulic), as advertised on the net by CJ Autos?