lanikus

@olli: you looked onto the wrong tire. I've ultrac sessanta's not just ultrac's !

For them, vredestein recommends 3.1f/3.1r which is 45psi either. So the only difference is on the front against what bmw is telling us.

But as you can see, you will not be able to give a general recommendation from car-manufacturers view. Different tire-types require different pressures. The right pressure is not only dependent on the weight and the construction of the car, but also on the constructional parameters of the tire itself.

The question of the right pressure is not so easy to answer.

The best result you will get is, when you use that make/model of tires the car-manufacturer mounts during production in combination with the recommendation of your door-plate. But who's using that combination?....

In my case, I checked the picture how my tires are standing on the ground and that looks good to me. I've 45psi front+rear. On the tires themself is written 51psi max.pressure, so I'm still below that limit.

Cu lanikus

Rudy

That's precisely why the car manufacturer's door plate has different numbers depending on the tire size and vehicle load. The easy answer to "what tire pressure should I use" is to say "use what the car manufacturer says on the door jamb." From there, you can adjust things to suit personal tastes and requirements...

BMW#7

The plate on my car suggests 2.2 front and 2.5 rear for normal load. But i've been running 2.3 front and 2.6 rear for almost a year, and I have had exceptionally good and even wear.

nicke60gre

I use 38/43 on mine and I have no problem with it.


Useful links about this topic:

http://www.carbibles.com/tyre_bible.html (scroll down this big page, until you find the tire pressure paragraph)

http://www.sportcompactcarweb.com/tech/020...pressure_guide/

my530i

Low tire pressure would cause bad gas mileage. I had 32psi all around for the last couple of weeks, and I can never go over 16.9mpg. I increase to 36/40 and I got 19.6mpg.
Time to increase to 50 psi all round to get mpg like a hybrid J/K

horatiub

on my 325i with Sport package, I have 35psi front and 41psi back

Ricracing

I fine discussion!

The car manufactures measures are those to go by.

Everyone has them in the B-pillar or see your drivers manual.


I use for everyday driving pressures in the middle of
given min and max for my size of tyres.

If one wants to save gas and have a unpleasant drive go for
the max measures.

But also notice the cargo recommendations.

Please also note that RF tyres can well be driven with very low pressures,
therefore check the tyre pressure once a month!

If you go and drive on a speedtrack put 50% above the max value.

tachyon

I boosted my tire pressure to 38 psi all around last week and I like this setting - nice balance of quite & comfort, but with a very solid feel when I toss the 550 around.

Lomag

38/42 is definitly the way to go! I'd put that extra bit in the rears if I were you!

pinguhk

I just checked my and itis only 34 all round I better up it up to 38/42 which I did and itis much better now thanks for you