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That's what it says on my car's door panel: 29F, 35R.

When repairing a flat today (nail hole) the tire shop said it's against their policy to go below 30 psi. The guy said 29 psi would be on the soft side. After a short conversation we decided to do 32 psi all-four tires.

How much pressure *should* I run? What pressure range might I increase it to without negatively affecting the tire wear/life?

These are conventional all-season (non-runflat) tires and I'm in a hot climate (90s to 100s summer days, mild winters).

[Tom K.]

Are you sure you have an E90? My '07 wagon calls for 32/39 for the basic 16" tires so if I were you, I'd try something like 32/36.

Tom

[bmw325i]

I have 35 all around but the sticker says 32/39

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Weird. 2006 325i. I've looked several times, it's 29/35. Do others with the base sedan have different recommended pressures?

EDIT: Just looked up the original Carfax I had saved. It was originally bought/driven in California. Any difference? Hmmm...different topic, but I wonder if I have a bunch of unnecessary environmental crap to slow the car down....

[VMRWheels]

I normally go 35ish all around. If the fronts are on the lower side, the tire will be more 'squishy' and your steering will feel somewhat disconnected.

[Surly73]

Make sure you're reading off the correct original wheel/tire size and speed rating. My sticker (Canada) has a whole chart on it.

My E39 which came with 235/45/17 Z-rated sport package speced 29F 33R. I bumped that up a few PSI front and rear to maintain the F/R balance. I supply that information just to let you know that yes they sometimes do spec <30. Every car, tire/wheel package and country could be different so people posting on the Internet "mine says..." without being very specific about what they have isn't really much help to you. I was having a conversation with a friend who bought a new Cruze and it's sticker recommends something like 28psi all around.

A lot of testing, measurement and calculation including load factors goes into those recommendations. It's always best to START your own personal tuning with the sticker pressures. I share discomfort with pressures as low as 29/33 so I believe I often held it around 32/35, 33/36. Try to preserve the F/R split if you can as it's a part of the handling. Higher pressures on an axle decrease grip at that axle - higher rear pressures are dialing out some of the factory understeer. If you change to an aftermarket setup then the stickers aren't right.

My E39 also had a "max weight" pressure listed which was something like 33/41. Some BMWs also have a "high speed" placard section too for sustained travel over 100mph. I believe my E90 has this. When on long trips where fuel economy was a concern, I would often add a few extra pounds of air.

[chromisdesigns]

Stock pressures on cars fitted with runflats are deliberately low, to minimize (to the extent they can) the horrible ride. When I still had the "bricks" on my car, I ran 32 in front and 35 in the rear. Now that I have **real** tires, I run 38-39 all around.

[Surly73]

Originally Posted by chromisdesigns

Stock pressures on cars fitted with runflats are deliberately low, to minimize (to the extent they can) the horrible ride. When I still had the "bricks" on my car, I ran 32 in front and 35 in the rear. Now that I have **real** tires, I run 38-39 all around.

Meh... My E39 had 29/33 on the sticker and runflats didn't even exist when that car was made. I'm not sure that your generalization is accurate.

[rogerdiaz]

Originally Posted by VMRWheels

I normally go 35ish all around. If the fronts are on the lower side, the tire will be more 'squishy' and your steering will feel somewhat disconnected.

Do you recommend 35ish all around for 19s non runflats sport suspension?