Saprissa

I keep my tire psi at about 2-4 above normal. Lot of highway driving.
I have both a C320 COUPE and C320 SportSedan. Definitely a bigger (heavier) engine than a 230K. Amdeutsch, interested about learning more about the weight balance up front, so I might have to adjust psi settings on front tires.

Both my C320's have staggered wheels (17x7.5 front / 17x8.5 rear).
And no, you cannot rotate staggered wheel set-ups.

DiamondNoir2K5

I understand that normal rotations involve all for wheels, so that's obviously not possible with staggered wheels.

But if you have staggered, wouldn't it make sense, at least from a left-right treadwear balance standpoint, to at least swap your left and right side tires/wheels from time to time? Do anyone do that?

Or is there something I don't understand about tire rotation that makes left-right swapping a stupid idea?

CitronC230K_03

most staggard wheels have directional tires, thereofre you can't do a left-right trade.

DiamondNoir2K5

Oh, I see. You learn something new everyday!

While we're on the subject, do any of you folks use an electric air pump to inflate your tires at home? Have any recommendations on a good brand or are they all just pretty much the same?

I'd like to do it at home instead of at a gas station because a) i won't procrastinate as much if i can just do it in my garage any time and b) i don't have to worry about cold vs. warm pressure adjustments.

Saprissa

that's exactly what I was going to say.

My MICHELIN PS tires, specifically say Direction --->
and the in-board side of the tire, says something like "face other side", I don't remember.

Carlos / Saprissa@aol.com

CitronC230K_03

they usually will specify which side goes inside and out. plus including arrows for the directionally challenged.

Saprissa

I haven't needed the use of an electric air pump. I had the tire pressure adjusted to where I wanted it when I had the tires/wheels installed. Since then, I check them every once in a while with an analog dial gauge, and haven't had to adjust. If I did, it probably wouldn't be that much off, since I go over a bit on the PSI. Nothing a quick stop at the air pump during a routine gas fill-up can't do. Plus, Service A & B intervals check for tire pressure too, and I just make sure to tell 'em just the way I like it. I would think most electric air pumps at reputable auto-shop stores are pretty much the same. I just wouldn't buy one at your local 99cent store.

amdeutsch

HTH

Link

DiamondNoir2K5

Oh. Yeah, that's exactly what I was talking about. Thanks.

TNblkc230wz

My coupe doesn't have have staggard wheels. The weight differences is about 50 Lbs over the front axle, but they can both have the trunk load the same

Nickle

Can someone let me know what the factory tire pressure specs are for the '05 SS 17 inch tires?

Thanks.

Blake P

Factory specs for tire pressure should be on the back side of your gas tank cover.

Nickle

OK, checking the back of the gas cap cover . . . hmmm, since my car is an '02, it doesn't have specs for the '05 17 inch wheels my car has.

Anyone have the specs? Thanks.

amdeutsch

Same as MY02 IAW Luke from the tirerack. Check/search the tire forum. HTH

Nickle

The specs for the '02 16s are 28 and 32 front/rear.

That seems awfully low for 17s.

I guess I'll search around.

Blake P

Sorry, from your post it was impossible to tell what kind of car you have. My bad!

Nickle

No prob! I searched the Tire forum, some seem to recommend using the stock pressures no matter what size wheels and tires are on the car.

That may or may be right, I don't know. But since these are the stock '05 Sport Sedan wheels, I'd like to run them at the pressures recommended by the factory for the '05 Sport Sedan.

Thanks!

DiamondNoir2K5

Nickle,

I have seen Luke post several times that you do your pressures more based on the weight and weight distribution of your car chassis rather than the wheels and tires. Therefore you would still go with the pressures printed on your gas flap.

Btw, on an '05 C230 Sedan where those wheels are stock, the pressures are still listed as 28f 32r. I just checked my tires today, I keep them at 32f 36r, which is 4PSI over factory recommendation.

vdubpower

what pressure do u guys run the stock tire/wheel 17s pressure at. i have a sport model. the gas tank lid says 28 ad 32, isnt that low? i think i have the continental tires on there, with 7000 miles

thanks

amdeutsch

There have been numerous threads on this subject matter.

RobertG

If you want better fuel milage run higher tire pressure like 32 psi
If you want better handling run lower pressure 28 psi.Car manufacturer knows what is best for their vehicle.Keep in mind that when the tire gets hot the tire pressure will increase.

MB-BOB

For best gas mileage and longevity of the tire, inflate it to the recommended maximum cold pressure on the tire sidewall, or no more than 5-10% less.

The pressure placard on the pillar gives suggested pressures, and is the same (standard) for all C-Class cars (standard sedans, sport sedans, and AMGs). However, there is a wide range of tires (sizes and aspect ratios) actually supplied with the car you buy. As a result, the TIRE can have vastly different max pressure values than the standard placard. Make sense?

My car came with 51psi Pirellis (16in), and I pretty well shortened their 60,000 mile life while following the placard and inflating only to 32psi. At 20,000 miles the tires were thoroughly worn on the shoulder tread (classic underinflation). I bumped the inflation to 42psi and then got another 8,000 miles of even wear from them. BTW, the ride quality was just as good at the higher pressure as at the lower. The tire maker engineers the tire for ride comfort at the pressure intended for each type of tire.

I seriously doubt the plus size tires (especially the 17in tires on the 230K SS) carry a 32psi rating (think MUCH higher). So, in my case, the "manufacturer knows best" adage is not good advice. My Dunlop SP Sport A2 replacement tires have 12,000 miles on them and they look nearly new. I inflate them to the maximum allowed, 44psi, and there is no uneven wear on the tread at all.

So, the rule of thumb is to be guided by the actual tire pressure value molded on the tire. Give the tire what it wants, not what the car wants. Makes sense, really.

mick1

I set the pressure on my front tires at 32 and rear tires at 34

MB-BOB

You guys with 230K SS really should read the max tire pressue value on your tires and then re-read my post (#4) above. Fair warning.

What is the Max pressure allowed on the 17s?

mick1

I got the Bridgestone Pozenta tires and the max pressure for them tires is 50 PSI