jacking up front end of 2005 highlander question

[NissanMaxima]

Hi all,
Looking at my manual's instructions for jacking up either front end or rear end of my used 2005 4wd highlander and it says the following:

"When jacking up the front wheels, release the parking brake and place wheel chocks only behind the rear wheels. When jacking up the rear wheels, place wheel chocks only in front of the front wheels." Later it says "when jacking up only the front wheels or only the rear wheels, place wheel chocks on both sides of the wheels touching the ground". Finally it says: "when lowering the vehicle with front wheels jacked up, release parking brake and place wheel chocks only in front of the rear wheels. When lowering a vehicle with rear wheels jacked up, place wheel chocks only behind front wheels".

Questions:
1) Is there a reason the parking brake should not be engaged? Does lifting up the front end with the parking brake engaged put excessive strain on the parking brake?
2. Why the contradiction in placement of wheel chocks when jacking up the front wheels? First it says to place chocks only behind rear wheels and then later it says on both sides of wheels touching the ground.
3. For lowering the front end, not sure why it says to release parking brake as presumably according to the first set of instructions, the parking brake is already off. And so are you supposed to remove the chocks behind rear wheels (or from both sides of rear wheels depending on which of the two contradictory instructions you follow), and only have wheel chocks in front of rear wheels?

 

[D60]

Don't know. So dumb. I'd ignore it all. Get the vehicle at the height you want, secure it safely (ie not just on a hydraulic jack) then chock the remaining wheels as necessary.

It's sad they had to pay somebody to write the gibberish in the manual as posted.

Typically if you're jacking the ENTIRE front or rear with a FLOOR jack RUNNING THE LENGTH of the vehicle, either the vehicle must get pulled toward the jack or the jack gets pulled toward the vehicle. For this reason you might want to be in N or have parking brake released. HOWEVER with IFS/IRS this scenario is rare and typically you're jacking a single corner from a pinch weld.

Maybe they're thinking a person is trying to align wheel studs with holes in a wheel in the event of a roadside flat and you'd have the parking brake set to keep the WMS from spinning.

But no, you cannot "over-tax" the parking brake by jacking -- it would be a useless parking brake if so.