Rexxarat

Hey!

I have been driving my GLC trying to get used to the new vehicle, but the ride is great. I am in VT and plan to travel quite a bit, so I come across the tire pressure issue to ensure safety of all who come aboard...

Please see the pictures and tell me if my tire pressures look okay given..




- I live in cold northeast
- These tire pressures are about 10 mile drive to stop and shop type.. speed capped at 55-60mph on a local highway
- In the evening, temp reaching 10-13 F
- Sports package. 19" AMG

Your 2 cent would be really appreciated.

Also, I think my windshield liquid is frozen? Because the manual says if it hits below 1L, the multifunction display would prompt me to add more fluid? I will pop up the trunk tomorrow morning to see what the deal is inside for sure. Anyone had this issue yet?



Thanks.

Rexxarat

bump.!

JEVA

I don't have mine yet so I can't comment on the second question but if you are within a few PSI of the recommended level you should be good. Sometimes people will run a little lower pressure in the winter to add traction but honestly I'm not sure how much, if any, that helps. Usually when it turns bitter cold, the tire pressure will drop as the air inside contracts and you may need to add some air.

rbrylaw

What Joe said!

Rexxarat

Thanks a lot guys.

I am expecting a long distance travel 300-400mi and wanted to make sure my tire pressures were all set to hit the road.

As to the windshield liquid, I think it froze... I popped up the hood and tried to pour some in but it took little and it was almost full again. Also because the manual says it would bring the warning light or something on the multifunction display, but it didn't. So it doesn't look like low level of windshield liquid but rather freeze. So I just need to wait and thaw ??

JEVA

Sounds like it, it should thaw from the ambient engine heat if you drive it for a bit. You should buy some washer fluid that is rated to handle the low temps there so it doesn't freeze again. The liquid freezing in the system could potentially damage components because of the expansion of the water as it turns to ice (though maybe the systems are engineered to withstand this). When it thaws, I'd check for leaks just in case.

fabbrisd1

Yes - many GLC's produced in Germany came to US early Fall with "SummerFit" windshield washer mix - since they were held at Port - that delay caused a glitch - and with unseasonable warm weather most areas of the country - that gliutch just got caught.

Washer fluid needs to be changed to "WinterFit" washer mix for our US winters - sorry - it's a "glitch" that was just caught here in the US - with dealer bulletin last week.

JEVA

Is there even an easy way to drain the system other than holding the spray until it runs low? I've never had to do that on any car before.
FYI - I wouldn't recommend running the sprayer until dry as it could burn out the pump if there is no liquid in it.

SteveE400

Turkey baster with a plastic hose on its nose?

JEVA

Well, there's that My mind was hung up on a drain plug or something

Rexxarat

One thing I find a bit odd on the MB recommended fuel-efficient tire pressure on 19" is like 32-35 front and 35-43 rear, but the actual max permissible tire pressure on these tires are around 50 psi.

Any thoughts?

Is MB recommendation really worth to follow to pump some air more or out?

JEVA

The max tire pressure listed on the tire is just that, the max. Do NOT follow this as a guide as to how much pressure should be put into the tire. Always follow the specifications in the manual and/or the sticker inside the door as in the image you originally posted. This is not just for fuel economy but also your safety. Over inflated tires can be dangerous and significantly impact the way the car handles and grips the road in a negative way - especially in the winter.

mdsbuc

+1

fabbrisd1

New MB's get delivered from the factory set at "transport" pressures - usually around 45psi.

At dealer checkin - that higher pressure is taken down to 30psi - then re-inflated (or exchanged if dealer does NitorFill).

On GLC'swhich are 4matic - I have my guys set at 38psi all around - even all around - same setting we have agreed for new deliveries GLE-SUV (except coupe), GL (except GL550, and same settings for G-Wagen.

On GLA's we set at 36psi.

Fuel filler door label is OK reference - both driver's doorpost and manuf recommendations are nonsense.

You "should feel" a driving difference going-up/going-down in about 2psi increment - if you choose to dial-in best "feel" for your personal preference - adjust by 2psi, drive for a week

JEVA

Say what?

Rexxarat

I agree with you on the fuel filler door label reference to be just OK.

Look at my case of the front two: when I turn on my car, the initial tire pressure estimate is around 33. The gas cap door label says 32 on normal 35 on max. I have run-flats by the way.

When I run on a high way, the front two heat up up to 35-36, even 37 from time, and this is with just two passenger in the car.

If I have to follow the fuel filler door label strictly, I would have to put my front two tire pressure down up to 30psi, so on normal road in high ways, it heats up just right in the range of 33-34 given the winter and its air contraction environment.

Would this make sense for you if you had 19" run flats? I am just very skeptical of the door label references.

But the rear ones have a larger range 32-42, so they are okay I guess... I am CONFUSED.

rbrylaw

Yes, of course as the car rides on the road, the pressure will go up. But the fuel filler door tire recommendation is not for tires that have been driven for an extended period, it's for ensuring the pressure is correct on cold (or relatively cold) tires.

mdsbuc

Indeed! Those fuel door recommendations are for cold temps only... done before any driving.

mikbar2

Tire inflation stickers for all cars sold in US are stated as cold ambient temps when adjusting.

DBV

We are in our third day with the GLC and temps this morning are 5 degrees in Cleveland. Our back windshield fluid and right passenger side fluid do not work. I wonder if it was delivered with summer washer fluid too? Sure hope so, as none of our previous Mercedes never had this happened. Our car was built in early Dec and delivered on Jan 15th.

sblvro

There is no summer fluid.

DBV

Whatever - so the opposite of the winter fluid then. I think you would get the point. That comment sure was worthwhile.

larrypmyers

Being familiar with the harsh Cleveland winter weather I'm thinking you will need to get your C in a heated garage, at least overnight. Hopefully this will be of sufficient duration to thaw your washer system.

With a temp. of five degrees you need to be concerned with hard freeze up rupturing a line or component in the system.

After you get it thawed out drain the system and refill with fluid formulated for winter temperatures. The folks at any auto parts store will know what you need.