bellavance

My C300 came with 225/50x17 RunFlat tires. Door Sticker specifies 39 lb front and 45 lb rear.

I've just fitted the car with regular Michelin X-Ice xi3 snow tires.

What tire pressure should I use with these tires?

Thanks.

PeteInGilroy

Great question, since I plan on swapping out my run flats for conventional tires after I take delivery of my C300 Luxury...Unless I hear some great ride advantages of the run flats. Is the suspension specifically tuned for run flats?

floridadriver

Without watching for unusual wear pattern, which would be too late, it's hard to say the correct pressure. Can you find from manufacturer the maximum weight at the maximum psi? May be able to come up with good estimate and then look for wear and adjust from there.

Pete, if they say they 'tuned' it for run-flats, I'd take that as jargon for they softened up the the ride a touch to compensate for run flats. In reading reviews, seems they notice when hit a pothole it 'crashes' more into the cabin with runlets (not just in this model). Bridgestone also has new runflat call Driveguard which supposed to be much more like conventional touring tire. (I don't have experience with it). Either way, what would you then do with your brand new OEMs?

bellavance

Pete,

What would you do about the lack of a spare tire and the absence of space to put one in the trunk?

mihaelb

Sell them, of course! probably even have some change left over after buying the regular new tires at that point

mihaelb

Buy one of those spray-can tire fixing things

floridadriver

Where's a good source to sell them? There's some on Craigslist around here now, Conti RF brand new, zero miles, asking $275 total for a set of 4. They're not very popular. Local tire store here buys used tires for $40 each if new, but states not interested in oem run flats. Bridgestone just came out this past spring with a new run flat called driveguard that is similar price as non run flats and highly rated and talked about on the bmw and mini forums. I'd be interested to do the same as you and get rid of the ioem ones if didn't basically have to toss them.

c4004matic

Ive done this before, but I did it since the OEM tires that came with my F150 were too bad to bear. I would keep the Conti till they wear out and then get normal tires. The Conti is in fact a very good tire. Essentially no one will buy your old "new" tires. The place where you swap them will most probably send them for recycling since they are loath to resell them, for liability issues. They are also a very hard sell since they are different sizes, how many cars in the market need staggered runflats?

bellavance

I have two Fix a Flat cans in my trunk.

bellavance

No staggered tires on the C300 Luxury model. 225/50x17

PeteInGilroy

I haven't asked the dealer yet, but I'm hoping they would do a swap for conventional tires. If not, I may run them for 6 - 12 months and then ditch them.


The C300 Luxury does not have staggered tires.


I'll have to research the Bridgestone Driveguard, as well as the newer self-sealing tires.


If I go with conventional tires, I would definitely store a couple of cans of fix-a-flat and an air compressor.


I imagine MBZ would still cover towing even if I had conventional tires.

c4004matic

I think the ditching plan will be the simplest. I hope to ditch the runflats too after a season and grab some Michelin Pilot super sports. Best tire in the market in my book. Mercedes does offer a compressor fixaflat system that fits nicely in the trunk hidden compartment. It actually works better than the regular fixaflat system since it uses the compressor to inject the goo.

Jinzen

36 PSI all around.

Actually that's the Tire Pressure the C300 4Matic Luxury calls for under normal load (oddly enough).

My C300 4Matic Luxury actually shows this on the gas door - 36 PSI All Around; 39F/45R under maximum load.

I run 36/40 right now, it really doesn't make a difference. I prefer slightly grippier up front. It goes to 39/44 after driving a while anyway. Dealer had set the pressures to 38 All Around at delivery.

Brampton

The decal on the Driver's door sill & the Gas door state 38F/45R.
The dealer has set it to 35psi. They insist that that's the way it should be.
Any opinion??