Recommended Tire Pressure in PSI

zeez_Dubai · 11-28-2010, 12:58 AM

Hello,

I have the OEM RFT R18 wheels that comes standard with the car.
what is the recommended tire pressure for front and back wheels in PSI please?

Not sure if this matters but i use nitrogen for the wheels.

tempreture in winter min is around 16C and in summer high is around 50C

thanks

Mr. ///M3 RD · 11-28-2010, 07:32 AM

Here you go have a read at the LINK below. Also have a look in your Driver Door Frame there is a Label that will show your front and rear recommended tire pressure.

Click here for the LINK

richard in NC · 11-28-2010, 07:50 AM

Exactly, it should be on the door frame. If you have changed your tires, all should be listed in the owners manual. But of course it says to refer to the door frame.

Note I always add about 1-2 psi to the recommendation. Especially when approaching the winter months, knowing it will be colder on some mornings. Plus I've found the RFTs ride better with a bit more air.

skier219 · 11-28-2010, 08:43 AM

Quote:

Originally Posted by richard in NC

Note I always add about 1-2 psi to the recommendation. Especially when approaching the winter months, knowing it will be colder on some mornings. Plus I've found the RFTs ride better with a bit more air.

+1

Mr. ///M3 RD · 11-28-2010, 09:34 AM

Quote:

Originally Posted by richard in NC

Exactly, it should be on the door frame. If you have changed your tires, all should be listed in the owners manual. But of course it says to refer to the door frame.

Note I always add about 1-2 psi to the recommendation. Especially when approaching the winter months, knowing it will be colder on some mornings. Plus I've found the RFTs ride better with a bit more air.

+1

Tip, if you take a long trip with the top down and perhaps a small suitcase in the trunk add 10% above the recommended air pressure for the rear wheels to avoid premature inside tire wear (due to trunk weight and the 2.5 degree rear wheel camber ~ this was recommended to me by a US major tire shop and confirmed to me by my very knowledgeable BMW Service Manager).

jadatis · 11-28-2010, 01:43 PM

Quote:

Originally Posted by Rolf-Dieter

+1

Tip, if you take a long trip with the top down and perhaps a small suitcase in the trunk add 10% above the recommended air pressure for the rear wheels to avoid premature inside tire wear (due to trunk weight and the 2.5 degree rear wheel camber ~ this was recommended to me by a US major tire shop and confirmed to me by my very knowledgeable BMW Service Manager).

You can also calculate it with spreadsheet I made, in wich I use the same equation and system, the car and tire-manufacturers use in Europe and since 2005 also in America. Also the camber-angle of 2,5 you can fill in for the pressure.
http://cid-a526e0eee092e6dc.office.l...0tyre-pressure
yust search for the needed data and if you cant work with it , give me the details, and I will give you a full report.
In the newest spreadsheet I use an even saver power in the equation.

Greatings from Holland
Peter

Mr. ///M3 RD · 11-28-2010, 06:17 PM

Quote:

Originally Posted by jadatis

In the newest spreadsheet I use an even saver power in the equation.

Greatings from Holland
Peter

Hi Peter,

Thanks for your post and effort to assemble such a comprehensive number of spreadsheet.

Unfortunately I use a Apple Computer running Mac OS X and therefore cannot open the spreadsheets.

My winter set is on all 4 corners 8x18 Wheels and 225/40/R18 Tires. (I think my pressure was set to 34 PSI Front and 38 PSI Rear).

My Summer set is front 8x19 Wheels and 225/35/R19 tires, rear are 9x19 Wheels and 255/30/R19 tires. Here I use during the summer front 40 PSI and rear 45 PSI. I use a bit higher then recommended here since I had some premature inside tire wear on my rear tires. (details in my garage). I do check my tire pressure on a weekly basis ever since I encountered two cracked wheels (my 19 inch rear wheels) this past summer.

Greetings from Canada

Rolf-Dieter

skier219 · 11-28-2010, 06:51 PM

Rolf, the spreadsheet works fine on my Mac, and even my iPad. As long as you have Excel, you can download it directly instead of displaying in the browser. Numbers should be able to open it too.

jadatis · 11-29-2010, 05:10 AM

@ rolf Dieter
If it still wont work the way skier219 wrote(was it all clear? pressentation is not my strongest point), I Need the next data.
1. maximum load or load-index of the tires, if you see on the side-wall"max load xxxx lbs/kg at yyy psi/kPa" then the xxxx is the maximum load. 225/40 R 18 91V
would mean load-index 91=maxload 615 kg, and V up to 240km/h max speed.
Quessing from your name, you can also read Germain site , I found, wich calculates it too.

of the car Gross axle weight rating ( GAWR), front and rear.
Also maximum technical car speed, and here the camber angle is above 2, so has to be taken into account. Then the empty weight would be nice and the weight and number of persons mostly in it and luggage. This for trying to determine the real weights on the seperate axle or wheel with spreadsheet I did not translate to english. If you can determine the weight on the seperate axles some way, I can fill that in in your own import to give an advice for your normal use.

If you are for instance mostly alone in the car, the pressure rear can mostly be the same as front or even lower, asuming the motor in the front. In Europe before 2000 it was normal to give advice on the stikker, for up to 3 persons and a little load, for wich the car maker determined the weights. After 2005 things chanched and they give ,to my opinion, much to high advice-pressures, for comfort ( normal 4 persons and load,for wich GAWR are used). To my opinion this is all because of the Ford/Firestone-affaire.

BlueZ4AZ · 11-29-2010, 01:14 PM

Recommended PSI is located on the sticker in driver's side door jam. Nitrogen makes no difference in terms of PSI.

cdeslandes · 11-29-2010, 01:38 PM

Quote:

Originally Posted by BlueZ4AZ

Recommended PSI is located on the sticker in driver's side door jam.

And in the manual!

cdeslandes · 11-29-2010, 01:40 PM

Quote:

Originally Posted by Rolf-Dieter

Hi Peter,
...
My winter set is on all 4 corners 8x18 Wheels and 225/40/R18 Tires. (I think my pressure was set to 34 PSI Front and 38 PSI Rear).
...

You may want to consider boosting rear pressure to 42 or 44 psi in the rear due to the narrower rear tires. Check the manual.

Irvillac · 12-02-2010, 06:41 AM

Having lived in Dubai and formerly driven a Z3M, I was advised to under-inflate slightly during summer using a nitrogen mixture and inflating to spec at this time of year. I would suggest going to the Pirelli service centre on the Sheikh Zayed Rd (between jct 4 and 3, if I remember correctly) - they seemed to know what they were talking about. I heeded their advice having had PZeros on the Z3M and my Audi RS6.
hope this helps.

11-28-2010, 12:58 AM	#1
zeez_Dubai Private 13 Rep 86 Posts Drives: Orion Silver Bmw Z4 35i Join Date: Dec 2009 Location: Dubai iTrader: (0)	Recommended Tire Pressure in PSI Hello, I have the OEM RFT R18 wheels that comes standard with the car. what is the recommended tire pressure for front and back wheels in PSI please? Not sure if this matters but i use nitrogen for the wheels. tempreture in winter min is around 16C and in summer high is around 50C thanks
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11-28-2010, 07:32 AM	#2
Mr. ///M3 RD Happy Camper 613 Rep 7,869 Posts Drives: C63 AMG & 280 SL on Weekends : Join Date: May 2010 Location: GTA, Ontario - Canada iTrader: (0) Garage List 1969 Restored Merce ... [7.50] 2011 M3 Coupe TRADED [7.34] 1987 BMW 535is [1.00] Cars from the Past [6.50] The ///M3 Engine S65 [9.59]	Here you go have a read at the LINK below. Also have a look in your Driver Door Frame there is a Label that will show your front and rear recommended tire pressure. Click here for the LINK __________________ Cheers, Rolf-Dieter Life will take us to some interesting places, fortunately The ///M3 will too with a many of us know this very well, now my C6.3 AMG with 487 HP does it too ---> Click here for some good stuff I found
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11-28-2010, 07:50 AM	#3
richard in NC Colonel 1229 Rep 2,602 Posts Drives: 2009 Z4 35i Join Date: Jul 2009 Location: Charlotte, NC iTrader: (0)	Exactly, it should be on the door frame. If you have changed your tires, all should be listed in the owners manual. But of course it says to refer to the door frame. Note I always add about 1-2 psi to the recommendation. Especially when approaching the winter months, knowing it will be colder on some mornings. Plus I've found the RFTs ride better with a bit more air. __________________ 2020 X3M non-comp, Alpine White over black : Exec Pkg, ventilated M Sport seats, 20"s 2020 M2 Comp, Sunset Orange/Blk: Orange stitching, DCT, exec pkg, bicolor rims Gone '18 M550i, '16 X4 M40i, '15 M5, '13 X3 35i, '12 335is, '11 X5 50i, '09 Z4 35i, '08 550i, 06 X3, 06 650i, '02 M5, '99 540i
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11-28-2010, 06:51 PM	#8
skier219 Captain 607 Rep 969 Posts Drives: X3 M40i, M2C, Ferrari 328 Join Date: Nov 2010 Location: USA iTrader: (0)	Rolf, the spreadsheet works fine on my Mac, and even my iPad. As long as you have Excel, you can download it directly instead of displaying in the browser. Numbers should be able to open it too.
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11-29-2010, 05:10 AM	#9
jadatis Private 12 Rep 86 Posts Drives: No BMW Join Date: Sep 2009 Location: Holland Europe iTrader: (0)	@ rolf Dieter If it still wont work the way skier219 wrote(was it all clear? pressentation is not my strongest point), I Need the next data. 1. maximum load or load-index of the tires, if you see on the side-wall"max load xxxx lbs/kg at yyy psi/kPa" then the xxxx is the maximum load. 225/40 R 18 91V would mean load-index 91=maxload 615 kg, and V up to 240km/h max speed. Quessing from your name, you can also read Germain site , I found, wich calculates it too. of the car Gross axle weight rating ( GAWR), front and rear. Also maximum technical car speed, and here the camber angle is above 2, so has to be taken into account. Then the empty weight would be nice and the weight and number of persons mostly in it and luggage. This for trying to determine the real weights on the seperate axle or wheel with spreadsheet I did not translate to english. If you can determine the weight on the seperate axles some way, I can fill that in in your own import to give an advice for your normal use. If you are for instance mostly alone in the car, the pressure rear can mostly be the same as front or even lower, asuming the motor in the front. In Europe before 2000 it was normal to give advice on the stikker, for up to 3 persons and a little load, for wich the car maker determined the weights. After 2005 things chanched and they give ,to my opinion, much to high advice-pressures, for comfort ( normal 4 persons and load,for wich GAWR are used). To my opinion this is all because of the Ford/Firestone-affaire. Last edited by jadatis; 11-29-2010 at 05:19 AM..
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11-29-2010, 01:14 PM	#10
BlueZ4AZ Go SU 33 Rep 902 Posts Drives: 2009 Z4 sDrive35i Join Date: Jul 2009 Location: Chandler, AZ iTrader: (0)	Recommended PSI is located on the sticker in driver's side door jam. Nitrogen makes no difference in terms of PSI.
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12-02-2010, 06:41 AM	#13
Irvillac New Member 1 Rep 5 Posts Drives: Z4 3.5i Forcetech Join Date: Jul 2010 Location: France iTrader: (0)	Having lived in Dubai and formerly driven a Z3M, I was advised to under-inflate slightly during summer using a nitrogen mixture and inflating to spec at this time of year. I would suggest going to the Pirelli service centre on the Sheikh Zayed Rd (between jct 4 and 3, if I remember correctly) - they seemed to know what they were talking about. I heeded their advice having had PZeros on the Z3M and my Audi RS6. hope this helps.
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