KJWLI

The tire pressure warning went off in my 2022 glc 300 4matic SUV. When I looked at the info on the side of the door the numbers seemed pretty high. I have Continental 235 55 R19’s. Are they high?
Thanks,
Kyle

Serhan

Yes, the door tire pressure is the safest tire pressure for max loading for driving over 100 mph as required by US DOT... You should check and use the tire pressure from the gas fuel door.

sn202020

Look at Fuel cap cover inside. 32~35 psi I like.

Instead of the door pillar label, which shows too high pressure somehow.

KJWLI

Who knew? The fuel door showed 32 PSI for front and back. I’m curious as to why there would be 2 stickers, in 2 locations showing 2 different sets of pressures. If one is for max load and the other for normal load, why not show both on one sticker?
Kyle

W205C43PFL

The one on the fuel cap is usually the better one to go with, as for the the one in the door sill since it complies with regulations that all cars have to have a sticker there, therefore there is a sticker there, the door sill one is usually a very high pressure. (Alright I realized I am bad at explaining and not exactly answering your question, I should step out...)

MBguy013

Don't forget that when you set the pressure to your desired setting, to reset the TPMS so that you don't continue to get the warning. It's in the service menu and simple to do.

W205C43PFL

Found the answer to the confusion: https://mbworld.org/forums/glb-class...ml#post8560757

jadatis

In earlyer days pressure was also given for upto 160kmph/99mph, and for 3 persons and a little load, for wich carmaker determined the expected axleloads.

Nowadays only for GAWR's and max technical carspeed. Or even for energy saving higher
41 psi is US XL P-tire referencepressure, and so often given and not calculated anymore.

But if based on GAWR's I expect motor in the back.
Will google your tire, expect it to be XL / reinforced/extraload and european system so AT 42 psi upto 160kmph/99mph.

Then I will give a pressure/axleloadcapacity - list with build in maximum reserve, at wich comfort and gripp is still acceptable. For that I give 90% of calculated axleload for 160km/99m/h

Then you " ONLY" have to determine the axleloads in your use 99% acurate, your responcibility and the most tricky part.

Then look them back in my list, and dont be surprised if it gives much lower pressures.
​​
Here the list only found XL /// loadindex 105 is maxload upto 160kmph/99mph of 925 kg / 2039 lbs AT 42 psi.
So list is for that max speed used, wich you wont go over for even a minute.
And max reserve.
If you want for higher speed, I have to make a new list.

KG axleload/ cold PSI/ LBS axleload.
783 kg/ 18 psi / 1727 lbs
821 kg/ 19 psi / 1810 lbs
858 kg/ 20 psi / 1893 lbs
896 kg/ 21 psi / 1975 lbs
933 kg/ 22 psi / 2057 lbs
970 kg/ 23 psi / 2139 lbs
1007 kg/ 24 psi / 2221 lbs
1044 kg/ 25 psi / 2303 lbs
1081 kg/ 26 psi / 2384 lbs
1118 kg/ 27 psi / 2466 lbs
1155 kg/ 28 psi / 2547 lbs
1192 kg/ 29 psi / 2628 lbs
1228 kg/ 30 psi / 2709 lbs
1265 kg/ 31 psi / 2789 lbs
1302 kg/ 32 psi / 2870 lbs
1338 kg/ 33 psi / 2950 lbs
1375 kg/ 34 psi / 3031 lbs
1411 kg/ 35 psi / 3111 lbs
1447 kg/ 36 psi / 3191 lbs
1484 kg/ 37 psi / 3271 lbs
1520 kg/ 38 psi / 3351 lbs
1556 kg/ 39 psi / 3431 lbs
1592 kg/ 40 psi / 3511 lbs
1628 kg/ 41 psi / 3590 lbs
1665 kg/ 42 psi / 3670 lbs/ referencepr
1701 kg/ 43 psi / 3749 lbs
1737 kg/ 44 psi / 3828 lbs
1772 kg/ 45 psi / 3908 lbs
1808 kg/ 46 psi / 3987 lbs
1844 kg/ 47 psi / 4066 lbs
1880 kg/ 48 psi / 4145 lbs
1916 kg/ 49 psi / 4224 lbs
1952 kg/ 50 psi / 4303 lbs
1987 kg/ 51 psi / 4381 lbs/ maxcold often given

Tmps going of when colder, must be seen as a secundary problem. often the borders and pressure settings can be changed, but mostly only upto a certain point.
My cold advice is measured at an ambiënt temperature of 65 to 70 degr F, and you can let it swing with ambiënt temperature and still no overheated tire-material, wich is main goal of pressure-determination.

Mind this is my conclusion in time, " tire-specialists" on RV forum state to fill determined best pressure at ambiënt temperature, whatever it is.
So then anticipate in a heated garage on ambiënt temperature you drive in, is a bit higher when driving in 40 degrF.

My system is easyer, only check if in line with ambiënt temperature, and dont fill up and let off air every time.

mikapen

Most of the above is overly complicated, improperly interpreted, and in some cases bogus. At least as it pertains to tire pressures on a specific car, which I think is what this thread is about.

Read the gas flap and set tire pressure accordingly. The other numbers don't really apply.

jadatis

I hope topicstarter apreciates my long story,
And only has to give tirespecifications.
I do my long story's to make you understand, once
​​​​you do, you can forget it an only remember what is important.