autoque

I have a European spec '08 S500 w/ AMG Sport Package which includes a 19" staggered setup. The tire sizes are 255/40R19 front and 275/40R19 rear.

Strangely I don't have a placard on the door pillar showing the recommended tire pressures, but there is one on the fuel cap and it recommends 29psi front and 32psi rear for the lightest load under 130mph/210kph.

But the placard doesn't say what tire size the recommendation is intended for. Neither does it say Sport package nor AMG wheels/tires, and I doubt Mercedes makes a different sticker just for the AMG Sport Package, and if they did, it would say on the sticker which trim the recommended tire pressure applied to. And I'm thinking maybe the fuel cap info is for S550s with 18". Or maybe they are the same. I'm confused.

Does anyone know or have a picture of the officially recommended tire pressure for the 19" AMG wheels? BTW I'm running on Hankook Ventus V12 Evo.

cool_lagoon

during cold tire use 34 psi if you are still using the original factory installed tires which is continental sport contach 2

starstylers01

29 and 32 is way too low. I have an s550 with the amg package but i think i have the 20" rims on mine.

The factory recommended psi is 38 for me

cool_lagoon

whether it is a 13" to a 22" wheel diameter, tire pressure is measured in lbs/psi for a 35 to 50 series tire 34 psi is enough, as you drive for a few miles the tire pressure increases and if you put 38lbs/psi, good luck and hope it does not blow up and cause an accident. unless your using nitrogen gas for your air. Tire/ Air running under heat pressure increases lbs/psi due to temperature and friction, will cause tire to expand and can cause serious accident or a blow out.

BTW which factory recommends the 38 lbs/psi and what tire brand, size are you using?

cool_lagoon

@autoque, tire pressure is not dependent on the tire size. let me put it this way what ever the tire size pressure per square inch (PSI) has nothing to do with the diameter of the tire, it has more to do with the tire profile, 35, 40, 45, 55 series etc. I strongly suggest all those who are not familiar with facts on tires go google this subject matter, tire and breaks are the most important component of a car in terms of safety.

autoque

Thanks for all the replies. I have a picture of the placard on the fuel cap door.

I really wonder why they have such conflicting info on it. I do think 29/32 is low but it's what the placard says...

See how it says +3 psi for 20" tires?

autoque

By the way, this figure's from the Michelin website. Just for a reference. Says 30/33.

The difference in ride quality between 29/32 and 35/35 is night and day.

starstylers01

I am using the factory Continentals I believe and the 38psi is the correct pressure. When I first bought the car they were set to this pressure. I also checked the info at the door and for my tires and wheels that is the pressure it recommends.

It also says to allow up to +4 for warm tire pressure, so thats about 42 psi. After warming up, mine usually go at about 40 psi

cliffhanger7

Sorry, I do not want to be irrelevant to the topic but I found it a useful confirmation to one of my tire issue concerns.
I also posted about tire problems on my 2007 S550. And one factor is the correct tire pressure. My placard on the fuel filler cover says 29-32 range and same info on the driver door pillar. For the Michelin Pilot Sport A/S 255/45-18, I found it too soft. I have upped the pressure to 35 psi and no improvement. Tires are wearing out on the edges, uniformly. Tires gone after just 13k miles. The conclusion was the tire sidewall flexes during turning. I changed tires to Continental extreme contact DWS 06. Tires are rated for 51 psi max pressure. By trial and error, I found that 37 psi is the least pressure to reduce my issue on tire improper wear. I mentioned this situation because my tire pressure info on the car appears to be wrong? too low. or MB revised it after my car built date? Anyway I am glad to know that the pressure I put on the tires are not too high or out of line. Now I can feel confident to up it to 38 psi which will give me slightly better margin for minimizing tire edges wear.
Thanks for the info.

DaveW68

32 PSI is the proper cold air pressure for that size wheel and tire. When the tires are fully warmed up, the pressure will increase about 4-5 PSI, which the mfr accounts for. If the edges are wearing prematurely, it is likely either out of alignment or you are very aggressive while going around turns, which will wear the outer edges. Overfilling the tires might be masking issues with your suspension or alignment. Also remember that your tire pressure will fall about 1 lb for each 10 degrees F the temperature drops. So you should check your tire pressure every couple of weeks to make sure it is around 32 PSI while cold.

konstantinos k

I understand what you're talking about but in my country cyprus which the asphalt temperature probably is around 60 or more celsius i use 40 psi no problem at all if i use less i will destroy the tyres

DaveW68

If you are running 40 psi cold tire pressure in an S550 (or S500 in Europe) on the standard 18" wheels, then you are going to prematurely wear out the inside treads of your tires. Going with the standard 32 PSI WILL NOT destroy your tires but will instead ensure that they last much longer. But you can confirm the correct tire pressure for your car by looking at the sticker on the inside of your gas filler door or on the door jamb of your driver's door.

If running the correct tire pressure is destroying your tires, then you have some major suspension or alignment issues that you need to get resolved ASAP.

Bamzilla

Recommended pressure should be on the inside of the gas door.

mnje350

What if the gas door specifies 32 front/33 rear and the door pillar specifies 36 front/39 rear cold? The manual says to refer to the door pillar. Car is a standard 2017 S550 with pierelli run flats. Conflicted about what I should use.

compaddict

iTrader: (1)

Gas door is king.
Vince

progonat

36 PSI is the magic number for both front and rear.

You can see actual labels here.

Bklyn

Absolutely. My father told me that as a kid. I got my love of cars from him. He always said, brakes and tires need to be good.

EasyPhil

39 is the magic number for a 2007 with AMG sport package.

Ninamashr

This is discussion is turning into a "What oil should I use" thread. lol