Tire pressure, which?

sardius · 11-01-2010, 10:49 AM

Quick question guys, the tire pressure on my winter tires, should I go with the tire manufacturer's pressure or the pressure marked on the door jamb (BMW)?

Thanks in advance

JimD · 11-01-2010, 11:00 AM

You always want to use the information on the door jamb. The tire manufacturer tells you the maximum pressure it is safe to put in their tire. The car manufacturer tells you the right pressure to use in that tire on that car for it to handle and brake right and wear well. If you use the maximum pressure the tire can take (from the sidewall of the tire), the car will not handle well and will wear out sooner (the tread in the center will disappear).

Jim

pinmagic · 11-01-2010, 11:09 AM

Years ago, I had my oil changed at Jiffy Lube. I asked the mechanic (and I use the term loosly) what pressure he had put in my tires. He said "50 pounds all around." I told him Toyota called for 29 pounds. His response? "It says 50 on the tires." So that IDIOT was sending EVERYONE out the door with max pressure in their tires.

ND40oz · 11-01-2010, 12:39 PM

Really depends on the new tires you're going with, if they're spec'd exactly the same, then yes, use the door jam pressures, or pressures specified in the owners manual depending on conditions (load, speed). But if you're changing tire sizes and different load specs, tire inflation requirements can change, especially if you plus size and change from an SL to an XL tire because of difference in load indexes. I've never minus sized before (which you may be doing with a winter tire, going to a 17 inch rim), so you may want to do some research based on your new tires specs. What tire did you go with?

sardius · 11-01-2010, 01:59 PM

Thanks guys for your replies, I am looking into the Blizzack WS70 205-50-17 winter tires...so I guess bmw recommendation?

ND40oz · 11-01-2010, 02:40 PM

Yeah, you should be fine with the BMW recommendation, which is 33F and 36R for a 205/50/17 85 H M+S. Your new ones are a 93T XL though, so a bit stiffer with higher load index. You may want to bump it a few PSI because of the XL rating, but check wear throughout the winter and you can adjust from there. XL rated tires reach their maximum load recommendation at 42 PSI vs SL tires at 36 PSI (Euro-metric).

http://www.tirerack.com/tires/tirete....jsp?techid=55

sardius · 11-01-2010, 02:48 PM

Thank you ND70oz

11-01-2010, 10:49 AM	#1
sardius Second Lieutenant 23 Rep 270 Posts Drives: 2011 135i Join Date: Jun 2010 Location: Toronto, Canada iTrader: (0)	Tire pressure, which? Quick question guys, the tire pressure on my winter tires, should I go with the tire manufacturer's pressure or the pressure marked on the door jamb (BMW)? Thanks in advance __________________ MY2011 135i / 6MT / Alpine White / Navigation / Premium Pack / BMW Performance Exhaust / aFe Pro Dry S
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11-01-2010, 11:00 AM	#2
JimD Brigadier General 369 Rep 3,547 Posts Drives: 128i convertible Join Date: Apr 2009 Location: Lexington, SC iTrader: (0)	You always want to use the information on the door jamb. The tire manufacturer tells you the maximum pressure it is safe to put in their tire. The car manufacturer tells you the right pressure to use in that tire on that car for it to handle and brake right and wear well. If you use the maximum pressure the tire can take (from the sidewall of the tire), the car will not handle well and will wear out sooner (the tread in the center will disappear). Jim __________________ 128i Convertible, MT, Alpine White, Black Top, Taupe Leatherette, Walnut, Sport Ordered 5/22/09, Completed 6/4/09, At Port 6/9/09, On the Georgia Highway 6/13/09, Ship Arrived Charleston 6/24/09 at 10pm, PCD 7/21/09
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11-01-2010, 11:09 AM	#3
pinmagic The Only Sane One Here 61 Rep 1,135 Posts Drives: 135i Convertible Join Date: Jun 2010 Location: Arlington, VA iTrader: (1)	Years ago, I had my oil changed at Jiffy Lube. I asked the mechanic (and I use the term loosly) what pressure he had put in my tires. He said "50 pounds all around." I told him Toyota called for 29 pounds. His response? "It says 50 on the tires." So that IDIOT was sending EVERYONE out the door with max pressure in their tires. __________________ 2011 135i VERT SGM/SB/MOONLIGHT - ED - with every single friggin' option they offered.
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11-01-2010, 12:39 PM	#4
ND40oz Major 409 Rep 1,349 Posts Drives: M2 CS Join Date: Dec 2009 Location: Denver/Frankfurt iTrader: (0)	Really depends on the new tires you're going with, if they're spec'd exactly the same, then yes, use the door jam pressures, or pressures specified in the owners manual depending on conditions (load, speed). But if you're changing tire sizes and different load specs, tire inflation requirements can change, especially if you plus size and change from an SL to an XL tire because of difference in load indexes. I've never minus sized before (which you may be doing with a winter tire, going to a 17 inch rim), so you may want to do some research based on your new tires specs. What tire did you go with? __________________ 21 BMW X5 xDrive40i 20 BMW M2 CS 19 Mini Cooper S Countryman ALL4 6MT
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11-01-2010, 01:59 PM	#5
sardius Second Lieutenant 23 Rep 270 Posts Drives: 2011 135i Join Date: Jun 2010 Location: Toronto, Canada iTrader: (0)	Thanks guys for your replies, I am looking into the Blizzack WS70 205-50-17 winter tires...so I guess bmw recommendation? __________________ MY2011 135i / 6MT / Alpine White / Navigation / Premium Pack / BMW Performance Exhaust / aFe Pro Dry S
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11-01-2010, 02:40 PM	#6
ND40oz Major 409 Rep 1,349 Posts Drives: M2 CS Join Date: Dec 2009 Location: Denver/Frankfurt iTrader: (0)	Yeah, you should be fine with the BMW recommendation, which is 33F and 36R for a 205/50/17 85 H M+S. Your new ones are a 93T XL though, so a bit stiffer with higher load index. You may want to bump it a few PSI because of the XL rating, but check wear throughout the winter and you can adjust from there. XL rated tires reach their maximum load recommendation at 42 PSI vs SL tires at 36 PSI (Euro-metric). http://www.tirerack.com/tires/tirete....jsp?techid=55 __________________ 21 BMW X5 xDrive40i 20 BMW M2 CS 19 Mini Cooper S Countryman ALL4 6MT
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11-01-2010, 02:48 PM	#7
sardius Second Lieutenant 23 Rep 270 Posts Drives: 2011 135i Join Date: Jun 2010 Location: Toronto, Canada iTrader: (0)	Thank you ND70oz __________________ MY2011 135i / 6MT / Alpine White / Navigation / Premium Pack / BMW Performance Exhaust / aFe Pro Dry S
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