BenzOwner02

Hi everyone, I am new here. I have a C240 02 and saw this forum and decided to subscribe. I need a favor please. My car came with stock 16s. I want to upgrade to 17s. I dont want to go any bigger for $$$ reasons. But I know that the C320 4 door sedan has about the same weight as my car and comes with 17s. Can anyone who has this car please tell me what the air pressure should be for the tires. This is usually located next to the drivers door once opened on the side. Thank you in advance I appreciate it.

Lynn

If you look at that sticker, you will see that it lists all the standard and optional tire sizes, including the 225/45-17. And all of them have the same inflation pressure.

Welcome to the forum.

BenzOwner02

Hey Lynn, thank you for your reply. However what you stated was incorrect. Each car has its own tire pressure. Mine only states what the pressure should be for 16's. Please if anyone has the C320 SPORT 4 DOOR can u please post the tire pressure posted on your door panel for 17inch. I really appreciate it. Thank you

quietflight

i run 32 psi all around on my c320 coupe with 17's but the recommended on my car is 28 front, and 32 rear.

BenzOwner02

quietflight , thank you for your reply as well. But I am going to assume from your tire pressure that your car weights a lot less than mine. On my door it says that for 16s I should have 28 front and 32 back. So now that I wanna go to 17s im sure it has to be more. Just not sure exactly. Again, anyone with the 320 4 door version please post the tire pressure. Thank you all in advance

Lynn

Every 203 I have seen, coupe or sedan, regardless of engine, has the same recommedation, 28 in front and 32 in the rear. The only car I don't know about is the C32. The difference is weight between the C240 and the C320 is only 60 pounds. Most of that weight is in the extra standard equipment in the 320. The only difference between the 3.2 and the 2.8 V6's is the stroke of the pistons. They should weigh the same and the weight distribution should be very close.

The sticker on my sports coupe shows two 16" tire sizes and one 17" tire size. The recommended pressure is 28/32 for all sizes. A similar question was posted in the tire forum by someone going to 18's or 19's. Lukes response was to use the pressures recommended on the sticker on the door frame.

BTW, an automatic Sports Coupe with the Panorama roof is heavier than your car with more weight on the front wheels. The recommended pressure is 28/32.

amdeutsch

I wish MB would be more specific in their statement; maximum load, cold, above 100 mph add 4, etc.

No flame Lynn.

I got my 225/45-17s at 28 all around without any wear problems. The MB recommendation is for maximum load. If you are like me, 90% the only person, then MBs recommendation doesn't make any sense because of the weight distribution of the vehicle.

BenzOwner02

Ok if thats the case then can someone please explain to me why the C32 AMG has 32 in the front and 35 in the back and its about 300 pounds lighter than my C240?

Also I went to a web site called www.tire.com and they had a section posted about air pressure. I have it copied below:

" Another valuable resource is the Tire Load/Inflation Tables. Your nearby tire dealer should have a copy. Not only will this document tell you the correct tire pressure for stock sizes, but it will provide the information on optional plus sizes as well. A good example would be the findings on a Honda Civic with the stock size 185/65R-14; recommended air pressure is 28 psi. Plus one size is 195/55R-15 with a recommended air pressure of 32 psi. Plus two size is 205/45R-16 with a recommended air pressure of 36 psi. Note how the air pressure increases with plus sizing to meet the load carrying capacity for the car."

I guess the only way we will solve this is if someone on this board who has a C320 4 DOOR SPORT that came stock with 17s can read the label on their door

But also if someone can also please give me a valid explanation for the 2 senarios on top that would be helpful as well. Thanks everyone

pokerFACE

probably wont help much to the thread starter's question,

but I run my 16s at 32psi front, 34 rear. handled much better than before... I found my tire pressures to be at 28/28..damn tire dealer!!!

BenzOwner02

Thanks Poker but we still need some answers to the above questions. If you know anyone out there with the C320 SPORT 4 DOOR please get us info. Thanks

Matt230K

Well, hopefully you will find someone who can tell you the recommended pressures for a C320 SPORT 4 DOOR.

But it really doesn't matter. The recommended pressures are usually on the low side for how most people llike to run them. Just try some different pressures and see what you like best. I would not go any lower than 28-32, but you can easily go to 34-36 or a bit higher.

BenzOwner02

sorry guys for bringing this post back but I am hoping someone who owns a C320 4 DOOR SEDAN can help me out. Thanks for your patience

new-c320

BenzOwner02

2003 C320 sports sedan recommended pressure 28 front and 32 rear.

Lynn

What a surprise.

BenzOwner02

hey newc320 did yours come with stock 17s?

If that is correct then why is the C32 FRONT 32, BACK 35? Thats weird

Lynn

The tire pressures recommended by the car makers are a compromise based on load rating, expected load in the car, tire wear, comfort and handling. Lower pressures result in a softer ride, while higher pressures result in better handiling especially a criper turn-in. Since the C32 is a more expensive, higher performance car, Mercedes felt that the owners of those cars would sacrifice a little comfort and maybe tire wear for better handling. I run 32 and 36 in my coupe because I prefer the crisper, tighter feel.

BenzOwner02

Thanks Lynn, but one more question, which tire pressure would give you better tread wear, the 28 32 or the 32 36? Thanks

Lynn

My rear tires seem to wear evenly, but even with 32 in the front, I am wearing the outside of those tires. 28 would make that worse. Of course, my car is somewhat more front heavy than your sedan. At least I think it is. 57% on the front.

Matt230K

Lynn, it's not even relevant what pressures you are running your tires at. You don't have a C320 SPORT 4 DOOR SEDAN.

BenzOwner02

true that matt, i just didnt want to be mean, lynn gave an effort, more than most people do, thanks

Matt230K

Notice the . Lynn, I hope you get it.

MB-BOB

I have a C320 4 DOOR SEDAN. I have a very knowledgable car sales broker who says to ignore what is printed on the door sill placard. Instead, he advises (for minimum tire treadwear) to always run the tires at their maximum permitted sidewall pressure rating.

The Pirelli P6 tires (16s) that came on my C320 say on their sidewalls that the maximum pressure is 51 psi. I currently run mine at 46psi, front and rear. They handle great, the ride is ever so slightly stiffer than at 32psi, and I hope to extend the wear for another 5K beyond the first 20,000, in which the tire wear has been extremely excessive when set at 28-32psi.

On my previous car, I had a set of Goodyear 225x50x17 Gatorbacks that I kept inflated to their maximum of 44psi... these tires wore evenly and lasted 52,000 miles.

BenzOwner02

Thanks BOB, but I think 46psi is too extreem for a car like this. I think I will just keep the tires at 35 psi all the way around. Hope the tread will last a long time.

MB-BOB

Point is... there is a wide range of pressures recommended by the tire manufacturers... depending on what tire is delivered to you on the car.

My (440 treadwear) Pirelli P6s are rated to 51psi on their sidewalls. I, too, thought that excessive, so I ran them at about 32-35PSI, for two years. After 20,000 miles the rear tires are worn within 1/32 of the tread wear indicators. Substantially more wear on the shoulders of the tire than in the middle, a sure sign of underinflation. So much so, that the MB dealer refused to rotate my tires as they should at my B service, citing safety reasons.

So, in my case the door placard is not an accurate indicator of what you should do with Pirelli P6s, because the placard is matched to what the engineers desire for the car, not the construction of the actual tire installed. The P6 certainly doesn't tolerate 32psi, which is not good considering that Pirelli does not offer ANY treadwear warranty on their EOM tires.