Suggested Tire Pressure

[x5turtle]

I am using 255/55/18 tires, they are michelin~ I just look under my door and it says 32psi for front and 39 psi for rear. I am just wondering~ cuz I have been driving on 49psi for 20k miles already, which the dealer set me up on... and when I found out yesterday, I release the air immediately. I just want to know~ cuz some of you saying that 32 for all four tires but the label under the driver's door is saying 32 for front and 39 for rear. please advise~

[UCrewX5]

In my opinion, 49 is WAY too high. Must have felt like you were riding on rocks. 32 all around is good for me.

[SuperGreg]

Originally Posted by x5turtle

I am using 255/55/18 tires, they are michelin~ I just look under my door and it says 32psi for front and 39 psi for rear. I am just wondering~ cuz I have been driving on 49psi for 20k miles already, which the dealer set me up on... and when I found out yesterday, I release the air immediately. I just want to know~ cuz some of you saying that 32 for all four tires but the label under the driver's door is saying 32 for front and 39 for rear. please advise~

49 WOW! 32 all around. Maybe it meant 39 rear with a full load?

[x5Monkey®]

Originally Posted by x5turtle

I am using 255/55/18 tires, they are michelin~ I just look under my door and it says 32psi for front and 39 psi for rear. I am just wondering~ cuz I have been driving on 49psi for 20k miles already, which the dealer set me up on... and when I found out yesterday, I release the air immediately. I just want to know~ cuz some of you saying that 32 for all four tires but the label under the driver's door is saying 32 for front and 39 for rear. please advise~

39 rear is mostly advised when carrying heavier weights in the rear. 49 is off the charts way too high, IMO.
my advice is to start off with 32 all around and play with the pressure to suit your taste. If your roads are pretty smooth then you might want to raise it up a bit, especially for some spirited driving. i run 35 all round, but do mostly highway driving. anything above 36 psi and i feel like i'm riding on balloons.

[kirkX5m]

i do mine @ 35
the weird thing you mentioned about the dealer though is once i dropped the m3 off for service and got it back with pressure at 49 also
INSANE?!!??!?!

[shahkg]

The servicemen at the stealers are idiots, they just put in air pressure until the tire looks round. They don't bother to take a reading, morons.

The different front/rear pressure are to induce understeer (make the car want to go straight when you turn) and therefore reduce the chance of "fishtailing". It's more for unexperienced drivers. I like to run 33/35, works for me...just like the understeer feeling. Also keeps the truck going in a straight line during highway cruising.

[Kewl X5]

I know that when they transport the cars, they do purposely put more air in the tire to help decrease the chance of flatspotting the tires. But once the car is sold, they should have put the proper tire pressure.


I think the maximum the side tirewall on the X5 tires are usually 50 psi so who knows maybe some monkey thought that was the proper tire pressure?

[joll]

I got 42psi all around

[x5rap]

I have a grille guard which adds 40lbs as far forward as you can put it. I run 34 front and 39 rear. 34 psi is 1 psi above spec. It sounds like my rears should come down a pound or two. 49psi is just wrong for the vehicle. You'll prematurely wear out the center of the tire and it'll drive lousy.

[x5turtle]

hmmm~ thanks for the advise~ I now go with 33psi front and 39psi rear~ polly will lower the rear a bit~
but my fuel consumption have decline alot after deinflating the tires from 49 to 33. Actually~ I enjoy the 49 psi ride more~ or maybe I started off my new car with 49~