Stoley

My local shop forman recommends 36 front, 38 rear. What do you put in your tires?

UUronL

Consult the manual. It has all the acceptable pressures for each given model, wheel/tire combination, and load.

znod

I checked the manual, the door jam, and talked with BMW service. Pressures in the neighborhood of 36 to 38 are way too high--probably lawyer pressures. After checking thoroughly, I decided on 30 psi to 32 psi all around when unladen. I think that above 32 psi is too high although not dangerous to a point, of course. I emphasize that I have the sport package/larger tires.

Above post slightly editied. Actually, I had decided on 30 to 32 all around. When I add air I put in 32 and then add again when the pressure gets to 30. I had forgotten what I am doing (30 psi all around is for my Z06, duh). And, as some are indicating, a little less in the front might be better. I put the same amount all around for memory ease. I have too many things to remember and seldom write things down. ~(:^)

cobradav

US Door jam data is typically higher due to liability issues perceived by mfrs. The data in Manual is generally lower and more appropriate to good vehicle performance, wear, etc. I think it is the best place to start and make slight adjustments based on your operation. But since they are generall lower, best to do frequent checking as u could get into a too low condition faster than if starting at higher pressures. I check pressures every car wash (at least weekly). Tires are cool and CLEAN.

gwf545

The table from the Owner's Manual:
All pressure specifications in the table are
indicated in psi/kilopascal with cold tires.
Cold = ambient temperature

...................................Light Load.........Heavy Load
...................................Front...Rear... ...Front...Rear
225/50R17 94 V M+S 32/220 38/260 38/260 45/310
225/50R17 94 W
245/40R18 93 Y
225/50R17 94 Q,T,H M+S


245/45R17 95 W.........29/200 35/240 35/240 42/290

245/45R17 95 Q,T.......29/200 35/240 35/240 42/290
H,V M+S
--------------------------------------------------------
Mixed Size

Front:245/40R18 93 Y....32/220............38/260
Rear: 275/35R18 95 Y....35/240............42/290

Front:245/35R19 89 Y....32/220............38/260
Rear: 275/30R19 92 Y....35/240............42/290


Compact wheel:
T 135/80 R 17 102 M...........61/420

But my door sticker says: 38 Front 44 Rear

Sorry about the format here, but it's not WYSIWG so I can't get it all to line up.

UUronL

I checked the manual, the door jam, and talked with BMW service. Pressures in the neightborhood of 36 to 38 are way too high--probably laywer pressures. After checking thoroughly, I decided on 30 psi all around when unladen. I think that above 32 psi is too high although not dangerous to a point, of course.
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I lost ~2 MPG of fuel economy when I moved from the door listings to the lower-pressure options listed in the manual. It did soften up the bumps though and likely improved grip.

Markymark

Our roads are kinda rough, so I use 31psi front, 32psi rear

heezy545i

I usually do 33/36. 32psi around for the staggered 18s seems a bit low to me.

About the current door jam listings, I believe manufacturers are now only required to list maximum recommended tire pressures.

ipse dixit

Depending on road conditions, weather, and the load you are carrying, I would suggest anywhere between 32 to 38 PSI.

If you want to dial out some understeers, try 38 (front) and 35 (rear).

If you have bumpy roads with lots of potholes, increase your PSI (i.e., 36-39 PSI) to protect from bent rims.

If you are carrying grandma and don't want her to lose her dentures, try 33 PSI all around.

UKAussi

Although not 100% sure, I believe one of the items BMW adjusted on my car after replacing the Dunlops under warranty was the tire pressure.
Too low pressure in the front with the sport package could lead to adverse wear on the inside edge of the front tires