But the TSB just covers
This information only bulletin has been issued to aid dealers to determine whether
windshield damage has been caused by an outside influence, or a manufacturing concern.

Nothing about 'jack crack'

 

Just to add some interest,this is from the 2002 vehicle care handbook.
I can't find any reference to this advice in the later handbooks.

Check the second bullet point down regarding jacking.

 

Norri, don't you think that's just a safety thing?
I've had a look at a number of windscreen repair websites and they mention 'stress cracking'
Stress Crack: A crack that occurs without anything hitting the windshield, typically due to a large variation in the temperature (such as when the car is sitting in the sun, and then you start it and use the air conditioning). It almost always starts at the edge of the windshield. Stress cracks will normally be a straight (or slightly bending) line, and will not have any sign of impact. A "pen test" is often used to determine if there is a stress crack -- a ballpoint pen is run along the crack, and if it dips anywhere, it is not a stress crack. That is because with a stress crack, no glass =actually comes off the windshield.

but nothing about jacking being a cause.

 

It maybe Steve.
Jacking on the corner is the "official" method documented by Jag, so I'd assume it was safe.
I've only had one wheel of mine and that's the way I did it.
However when oil change time rolls around I think I'll be heading for the cross member.

 

I'm with Steve on this one - the references in the literature are all to satisfy the health and safety terrorists/litigation lawyers. So....... urban myth or not? Has anyone experienced a cracked windscreen through jacking?

 

You guys should've seen my '83 XJ6. Jacking up the front of the car meant that the doors wouldn't close properly. I'm shocked that all the windows didn't simultaneously shatter on that car!

 

To deform permanently a structure like the chassis you have to exceed the elastic limit of the elements.
I can (sort of) imagine that the elastic deformation might cause a door to jam while the car was on the jack but going into plastic (irreversible) deformation involves forces beyond anything that could be applied via a jack on one wheel.