Manual/Rim says to inflate spare to 61 PSI. Sidewall says 60. Should i got 60 or 61?

 

 

I highly doubt that 1 PSI will matter much when your talking about the range of 60's in PSI... But I would always go by sidewall suggestions rather than manual suggestion.

However, are you SURE that it says 60 PSI? That's rather high - even for a spare. Does it say MAX PSI 60, or recommended?

 

all my donut spares says 60 PSI. im 100% positive. will take picture tommorow. too cold in canada right now

 

Mini-spare tires as we have in these cars are normally a standard PSI of 60. 60 or 61 makes absolutely no difference. I usually overinflate my spare by 5 PSI anyway just so it lasts a bit longer before becoming too low. It really makes no difference if you're within 10 PSI of target on the spare.

 

No problem with small overinflate. Better 61.

 

It depends on how it is written on the sidewall.
If it states " maximum load xxxx lbs AT yyy psi ( cold)"then this is the pressure at wich the maximum load may be bare up to mostly 160km/99m/h.
This pressure is called the reference-pressure in the formula that the tire-makers use to determine the needed pressure for lower then maximum load on the tire.
If it states "maximum pressure 60 psi(cold), then it is the pressure where you may not go over when tires are cold ( so not driven with for a time).
But then even the this 1 psi would not be a problem for the spare.

But your tires are probably normal car tires or Extraload/reinforced/XL.
The difference then between reference- and maximum-pressure is used for higher speed and camber angle( alignment) of above 2 degrees.
Read about Toyo tires on a Westfield ( kittcar) with these maximum pressures, wich is higher then mostly, even for an XL.

But you can calculate the needed pressure with one of my spreadsheets.
In them I still use the European formula and its addings for speed and camber-angle, but am planning to rebuild them to my own formula.
You can read more about it on my public map on my skydrive , that belongs to my hotmail-adress with the same username as here.
I will give you the link to the map for recalculating for other then OEM tires, but can also be used to check the original.
My quess is that for an MB you can also go verry low in the pressures, like for the Westfield, but calculate it to be shure.
Then you can go lower for the spare too.
Could also be that the 61 psi was a miswriting in the manual.

https://skydrive.live.com/?cid=a526e...E092E6DC%21235
To use a spreadsheet, click on the line but not the name of it , then in the right barr the info apears, with also reactions, that you can give yourselfes also. There click on Download, and after download and eventual virus-check, you can open it in Excell or compatible programm ( Open-office-Calc fi) to use it. If you press wrong , it will be opened in the browser, but this cant handle some things , I used in the spreadsheets, so gives notice of that.
Then press "Skydrive at the top of page and go back and try again.
If you cant work it out, give me the details , and I will use it as an example here.
From this link you can navigate my complete public map, for more about calculating tire-pressure.

After this all you will see the stated pressures in its contence, and wont be bothered about this little difference.

 

61 psi is both written in manual and on the rim. check it on your own W204 or similar benz.

 

I dilemma over 1 pound of air? el oh el...there are bigger issues in the world to worry about

 

+1. Especially as there is only a slim chance you are ever going to use it.

 

You might want to edit your original and subsequent posts to indicate that you are talking about the temporary spare tire. On the other hand, I have read at least one thread here where the OP thought that the standard road tires should be inflated to the maximum pressure stated on the sidewalls. In any event, be they automotive or golf cart or bicycle tires, follow the numbers molded into the tire. The folks who built the tire know what they are talking about. Plus or minus a few % points won't cause any harm.

Wayne

 

i did mention spare in my original post.......

 

I apologize. I missed it the first time. I am sorry.

Wayne