225/45zr17 tire pressure

[HW]

i've done my due diligence search and have not found info on factory recommended tire pressures for 225/45zr17 summer. seems like my factory tag is missing the O symbol for the rear tire pressure.

strangely, it lists 29psi (4 passengers) as the one for the front which seems low to me. and 33 for loaded front. :dunno:

for 225/45/zr17 m+s it lists 36/44 loaded and 32/36 for 4 pass.

seems to be a wide rage? :dunno:

[Pinecone]

Personally, I would jut put 38 - 42 all around.

The higher front pressure will give more neutral handling. The higher overall pressur will give better cornerin, better turn in, better braking and most times, longer tire life. The downside is a slightly rougher ride.

I use the factory recommendation as a basic start, but even then I normally add 2 -4 psi to their recommendations.

[kyfdx]

i've done my due diligence search and have not found info on factory recommended tire pressures for 225/45zr17 summer. seems like my factory tag is missing the O symbol for the rear tire pressure.

strangely, it lists 29psi (4 passengers) as the one for the front which seems low to me. and 33 for loaded front. :dunno:

for 225/45/zr17 m+s it lists 36/44 loaded and 32/36 for 4 pass.

seems to be a wide rage? :dunno:

Since your tag is gone.. I will tell you what mine says.. '03 325i Sport

30psi front/35psi rear.

[HW]

wouldn't 38-41psi promote uneven tire wear down the centre?

i have 34F/36R right now. i remember KP said that he had excessive centre tire ware so he went down to 32 all round. but running that low gives an aweful ride. :dunno:

[drmwvr]

i've done my due diligence search and have not found info on factory recommended tire pressures for 225/45zr17 summer. seems like my factory tag is missing the O symbol for the rear tire pressure.

strangely, it lists 29psi (4 passengers) as the one for the front which seems low to me. and 33 for loaded front. :dunno:

for 225/45/zr17 m+s it lists 36/44 loaded and 32/36 for 4 pass.

seems to be a wide rage? :dunno:

I asked this question sometime back. Here is a link to the thread were we discussed it. Never had any concrete conclusions :dunno:

http://www.bimmerfest.com/forums/showthread.php?t=40443

[HW]

I asked this question sometime back. Here is a link to the thread were we discussed it. Never had any concrete conclusions :dunno:

http://www.bimmerfest.com/forums/showthread.php?t=40443

thanks! it appears that the numbers given on my ('00 323ci) door jam is lower than yours which perhaps was the reason for the premature cracking of the sidewall on my oem conti tourings. :confused: :mad:

and no tech bulletin from bmw of the change :mad:

[HW]

I asked this question sometime back. Here is a link to the thread were we discussed it. Never had any concrete conclusions :dunno:

http://www.bimmerfest.com/forums/showthread.php?t=40443

in the tag, do you suppose 225/45R17 91 W refers to "winter" or "W" speed rating? :dunno:

strange. yours list 30/35 w/ the triangle (325) and mine (323) lists 29/33 w/o any symbols next to it.

[drmwvr]

in the tag, do you suppose 225/45R17 91 W refers to "winter" or "W" speed rating? :dunno:

strange. yours list 30/35 w/ the triangle (325) and mine (323) lists 29/33 w/o any symbols next to it.

That's a good question; I don't know. Since I have 225/45ZR17s (Z-rated) I do not get the W, H, M or Q alphanumeric code after the tire size. Regardless, I have been running 34f and 38r with good results. Interestingly enough, when I had my first oil change at the dealership, they put 40psi in all four tires :dunno:

[HW]

That's a good question; I don't know. Since I have 225/45ZR17s (Z-rated) I do not get the W, H, M or Q alphanumeric code after the tire size. Regardless, I have been running 34f and 38r with good results. Interestingly enough, when I had my first oil change at the dealership, they put 40psi in all four tires :dunno:
the Z rating has now been divided into W and Y ratings. the Z rating is anything above 149mph which was open ended and didn't say that it cannot be used above say 250mph. the W and Y rating fixes that abiguity. W is good for upto 168mph, Y is good for upto 186mph. the V/149, H/130, U/124 ...

most Y and W tires are labeled ZR on the sidewalls (i think).

so how's your tire wear on 34/38?

[drmwvr]

the Z rating has now been divided into W and Y ratings. the Z rating is anything above 149mph which was open ended and didn't say that it cannot be used above say 250mph. the W and Y rating fixes that abiguity. W is good for upto 168mph, Y is good for upto 186mph. the V/149, H/130, U/124 ...

most Y and W tires are labeled ZR on the sidewalls (i think).

so how's your tire wear on 34/38?

Interesting, I wonder what the Q and M designations are for?

In regards to tire wear, so far so good. However, I only have 15k miles on the odometer so I would not expect to see too much wear. The tires appear to be wearing level and I do like the way it rides with 34/38. FYI, I have Bridgestone Turanzas.

[exoticar]

Thinking of buying a new BMW 750 LI and would like help as to what tire would give me the smoothest ride. High speed is not my interest, a smooth rides is what I want