Correct Tire Pressure/Different tires-need help

So, I'm relatively new to the world of Bimmers, here's what i'm looking at

My car is a 2000 528i w/ Msprt pkg

Tires: I have four Continental SportContact 2s, dimensions 235/45 R17 93Y Radial Tubeless. The pressure in all four of them is 30psi. Now the panel on the door says fronts should be 33psi and the rear should be 41, but that's for a 255/40 (rear). And the tires say no more than 40 psi. Sorta confused, who's the boss when it comes to the tire pressure? Should I take the rears up to as close as 40psi as possible? Or should I leave them all about the same. the car's driving nicely, wonderfully in fact, and I'm not tempted to mess with anything for fear of it backfiring.

One other thing- the Wiki says to use a good 0w-30, but the guy who had the car before me had taken it to a BMW service center (in Germany, we're both stationed over here), and they had been using 0w-40. Which is the best bet? Or does it not even matter? Sorry for such stupid questions, i'm not a mechanically inclined guy, but I'm trying to learn. thanks

Tim

noone willing to help?

Just wanted to make sure I'm in accordance with the new member regulations "take pictures or it didn't happen." i literally just snapped them, it's dark outside, they're godawful pics, but will work for now.

not sure if this will help.. but i have a 2003 525i sport with 235/45/17 wheels. i use 35 psi on all of them

30 seems a little low, but considering your max is 40, 32-35 should be OK
0w40 if that's what BMW says

file's too big

thanks

Depending on the type of tyres, the conditions in which you drive, and the loads that you put on the tyres, you could fill them anywhere between 30 and 45 (provided that's not above the max fill). Play with it and see how it feels. I'm following BMW's spec with my Hakkapellitas and it's improved handling greatly from the 28psi the shop put in :-\

I run 32F 34R. Higher than that I find too jarring, plus usually very little weight in rear: two little kids combined weight 60lbs. Check your pressure regularly as (as you know) it will fluctuate based on ambient air temp.

I run 32-35 psi in ALL of my cars/family van, never have any issue with uneven wear etc.

This is what I do:
- WINTER 5W30 Synthetic oil
- SUMMER 10W30 conventional oil
Change oil every 5K miles or so.

word, thanks.

i put 33 in all four tires and noticed a slight change (for the better) in handling. Although, I'm probably putting snow tires on today... oh well. And i went with 0w-40. Thanks again.