I was checking tire pressure in manual and was surprise to see that the SQ5 needs 39 psi for 255/45R20 101W. What is more surprising it that the 2.0T and 3.0T with those same tires only requires 29 psi!
Does the SQ5 require higher pressure simply to support its higher top speed?
Good question, i'd be interested in other's thoughts and feedback on this too...also, although it states (as Yoshimura points out) in the Owners Manual indicates the 39psi for 255/45R20 101W, yet inside the Driver's side door on the B-pillar it indicates 41psi and i've found the Audi Service department sets the tires about 2-3lbs less??
Explorer fiasco fallout; the history drivers to these tire pressure questions
What you guys are finding here in part is from the Ford Explorer/Firestone rollover fiasco. As a result of that, the requirements for door stickering were changed in USA. A guess is that Canada follows the same since the stickers also have the French language police baloney. That sticker change occurred circa 2007. Since then, all vehicles have the standard white background sticker with the black, yellow and red print. All standardized and legislated down to the font, size and colors. The listed tire has to be exactly what is factory mounted on the car too--no multiple tire sizing listings anymore for example. My Mini S got recalled for a slight sticker error where they dared list two wheel sizes or got wrong what they installed on the car. The location was also mandated on the drivers jamb. For those who have owned older Audis, you know the sticker usually used to be on the gas tank lid, or sometimes on the rear passenger door fender well area.
What also happened is the sticker is now mandated to provide the settings at the maximum load only. Again, for older Audis, they always used to have the lighter load and heavier load settings (5 people figures and some luggage, vs. two people figures and less luggage). Those assumed you could actually make a somewhat intelligent personal decision based on a range. In turn, on the SQ5 specifically, it will be somewhat heavier than a V6 Q5 and more so than a 2.0T, and its standard equipment higher. Those will drive up its spec. listed weight. It also has the higher performance level, and its governor set higher (not real world relevant other than Germany basically). The US stickers can now also vary from the stickers in other markets, even with the same tires and same motor. Some guys fleshed that out on some VW stickers a few years ago on a different board when posters across continents compared stickers and eventually pictures and realized they didn't match up even for same motor and same year.
Meanwhile, the companies have more liberty in what is in the manual than on the sticker. My belief--especially when people find cross continent variances in the stickers--is the manual is the better guide if you want to use some judgment. Thus you can usually still find info on load and pressure differences and for other tire sizes. That info presumably comes from their experience in Europe with its potential for higher and extended speed runs. But with some of the usual cautions you could choose to interpolate over to a similar general weight vehicle--basically any the the choices except the (non-Hybrid) 2.0T. If you can get back to what the true Euro stickers still say for a given motor, then you will know what Audi the manufacturer actually thinks is best, without a bunch of lowest common denominator Explorer fiasco regulatory think overlay piled into the dumbed down sticker now on your door jamb. Owning a pre-2007 Audi A8 with a high end motor, I can confirm there that with the identical wheels and tires, the W12 setting are likewise a fair amount above the standard 4.2 settings, pre-nanny Explorer "old style" sticker-to-sticker direct compared. in turn, also has 600 pounds more weight, almost 50% more HP, factory stepped up brakes and a notch stiffer roll bars. Presumably similar analogies to the SQ5.
Finally if I were any of high speed sustained running (I don't mean 65-70), especially in hotter climates, or I was trailering, i would be up at the max load rating per either the sticker or the book.