Tire PSI
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Member
Joined: Dec 2009
Posts: 118
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From: Canada
Me, 2008 Hummer H2 Wife, 2010 Mercedes GLK350
Tire PSI
I have the 20" wheels, and just checked the tire pressure, it was 29-31 PSI.
What does everyone run their PSI at?
I pumped them all up to 35, it says 50 max.
I've read that if you run tires at the max PSI you will get better gas milage. The old idea that you will wear your tires out is based on old bias ply tires, radials can safley be run at the max pressure cold without doing any damage to the tire. ( So I've been told! )
What does everyone run their PSI at?
I pumped them all up to 35, it says 50 max.
I've read that if you run tires at the max PSI you will get better gas milage. The old idea that you will wear your tires out is based on old bias ply tires, radials can safley be run at the max pressure cold without doing any damage to the tire. ( So I've been told! )
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From: Northern NJ
GLK 350 / Porsche 993
Never heard this before. MAX doesn't mean what it should be run at. When tire warms up, PSI increases, so 50psi cold maybe much higher when you are driving and tire warms up.
33 is recommended for 20's (check the inside of the fuel door). Tire pressure might have been lower due to colder weather in your case.
33 is recommended for 20's (check the inside of the fuel door). Tire pressure might have been lower due to colder weather in your case.
Thread Starter
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Joined: Dec 2009
Posts: 118
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From: Canada
Me, 2008 Hummer H2 Wife, 2010 Mercedes GLK350
On the tire it says, Cold 50 PSI max.
I would think if they were at 50 PSI, the ride would be very hard, and if you hit a pot hole, you would wreck the rim!
I'll try them out at 35PSI and see if I notice any difference in MPG or ride.
I would think if they were at 50 PSI, the ride would be very hard, and if you hit a pot hole, you would wreck the rim!
I'll try them out at 35PSI and see if I notice any difference in MPG or ride.
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Joined: Sep 2009
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From: Chicagoland
2008 ML350 4matic
yikes! max pressure....might as well get solid tires. The ride comfort would be like riding in an old Radio Flyer wagon hitting every sidewalk crack...You will get better fuel mileage with increased air pressure. The contact patch will continue to round out with the increase in pressure....less surface touching the road, less resistance....better mileage. But, less contact equal less traction, less stability, and a greater chance of a catastrophic failure at higher speeds....
I like to go 2 lbs higher than the recommended in winter and then the recommended pressure the rest of the year, and I check it weekly.
I like to go 2 lbs higher than the recommended in winter and then the recommended pressure the rest of the year, and I check it weekly.
Member
Joined: Feb 2009
Posts: 163
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From: Far West Texas
GLK 4Matic
When I had my tires rotated by the dealer, they put them to a pressure I don't remember right now. What I do remember is that they were about 2 pounds different between front and back. I got home and put them back to what the sticker in the fuel door says. I didn't want to argue with the tech but I just don't see how that could be correct while having 4matic. To me, it would put a strain between to the front and rear.
Also, putting your tires at max will give you a more solid ride and bad wear patterns. I know Obama wants everyone to air their tires up max is just way to much.
Also, putting your tires at max will give you a more solid ride and bad wear patterns. I know Obama wants everyone to air their tires up max is just way to much.
Thread Starter
Member
Joined: Dec 2009
Posts: 118
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From: Canada
Me, 2008 Hummer H2 Wife, 2010 Mercedes GLK350
yikes! max pressure....might as well get solid tires. The ride comfort would be like riding in an old Radio Flyer wagon hitting every sidewalk crack...You will get better fuel mileage with increased air pressure. The contact patch will continue to round out with the increase in pressure....less surface touching the road, less resistance....better mileage. But, less contact equal less traction, less stability, and a greater chance of a catastrophic failure at higher speeds....
I like to go 2 lbs higher than the recommended in winter and then the recommended pressure the rest of the year, and I check it weekly.
I like to go 2 lbs higher than the recommended in winter and then the recommended pressure the rest of the year, and I check it weekly.
So do you run 35 PSI in the winter and 33 in the summer?
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From: Northern New Jersey
2010 GLK Black, Premium 1, Lighting, Multimedia, Appearance and Media Pkg, 2012 Corvette Grand Sport
You need to remember to reset the tire pressure monitor system so the system knows what the new calibration point is. If this has never been done and the tires are under inflated you may not get a warning.
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Mercedes Benz GLK-350
I have the 20" wheels, and just checked the tire pressure, it was 29-31 PSI.
What does everyone run their PSI at?
I pumped them all up to 35, it says 50 max.
I've read that if you run tires at the max PSI you will get better gas milage. The old idea that you will wear your tires out is based on old bias ply tires, radials can safley be run at the max pressure cold without doing any damage to the tire. ( So I've been told! )
What does everyone run their PSI at?
I pumped them all up to 35, it says 50 max.
I've read that if you run tires at the max PSI you will get better gas milage. The old idea that you will wear your tires out is based on old bias ply tires, radials can safley be run at the max pressure cold without doing any damage to the tire. ( So I've been told! )
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Nissan GT-R BE / '12 Ducati-1199 Panigale S / '12 C300-4M Loaded/GLK350-4M Loaded
I have the 20" wheels, and just checked the tire pressure, it was 29-31 PSI.
What does everyone run their PSI at?
I pumped them all up to 35, it says 50 max.
I've read that if you run tires at the max PSI you will get better gas milage. The old idea that you will wear your tires out is based on old bias ply tires, radials can safley be run at the max pressure cold without doing any damage to the tire. ( So I've been told! )
What does everyone run their PSI at?
I pumped them all up to 35, it says 50 max.
I've read that if you run tires at the max PSI you will get better gas milage. The old idea that you will wear your tires out is based on old bias ply tires, radials can safley be run at the max pressure cold without doing any damage to the tire. ( So I've been told! )
SD90 you are very lucky your tires have not exploded...
NEVER EVER load your tire to the max reading on the side of the tire... use the tire pressure chart sticker inside the door jam... and these readings must be done when the tires are cold.
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GLK 350
The TPMS has been one of the most annoying systems on the GLK. It's already back in the shop to have the module replaced for a second time.
I also hate the fact that the system only tells you that in general there's low tire pressure. Why can't it just show me which of the tires is below the threshold as oppose to me having to try and figure out which one(s) it is and then adding/removing air? It seems that most other vehicles will tell you the tire pressure in each individual wheel.
I also hate the fact that the system only tells you that in general there's low tire pressure. Why can't it just show me which of the tires is below the threshold as oppose to me having to try and figure out which one(s) it is and then adding/removing air? It seems that most other vehicles will tell you the tire pressure in each individual wheel.
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Posts: 173
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From: Colorado
2012 C350 Coupe Loaded
The TPMS has been one of the most annoying systems on the GLK. It's already back in the shop to have the module replaced for a second time.
I also hate the fact that the system only tells you that in general there's low tire pressure. Why can't it just show me which of the tires is below the threshold as oppose to me having to try and figure out which one(s) it is and then adding/removing air? It seems that most other vehicles will tell you the tire pressure in each individual wheel.
I also hate the fact that the system only tells you that in general there's low tire pressure. Why can't it just show me which of the tires is below the threshold as oppose to me having to try and figure out which one(s) it is and then adding/removing air? It seems that most other vehicles will tell you the tire pressure in each individual wheel.
Junior Member
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GLK 350
Is this just a software update or both hardware and software? My GLK is in the shop now getting the TPMS issue resolved and it'd be nice if it was just a software/firmware update that would display individual tire pressure.
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From: Colorado
2012 C350 Coupe Loaded
Kinda sucks I know.
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From: Old Dominion
2015 VW GTI.S4; 2016 Audi Q3 Prestige
The 2011 Manual says on pg.266:
you will find a table of recommended tire pressures on the Tire and Loading information placard on the B Pillars on the Driver Side.
You will find a table of tire pressures for various operating conditions on the inside of your vehicle's fuel filler cap.
However, the info @ each location contradicts each other with:
the fuel cap saying:
33F/33R Normal Load
35F/39R Heavy Load
the door jams has 2 placards saying the same but without load suggestions:
35F/39R
See attached in same order as describe above.
What is the right PSI?
Last edited by MBNA109; Nov 1, 2011 at 11:48 PM.
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From: East Texas
2004 Volvo XC70; 2012 GLK 350 4matic
My vote goes to the fuel door numbers.
We should all call MBUSA and tell them to correct the door numbers.
Wayne
We should all call MBUSA and tell them to correct the door numbers.
Wayne
Last edited by venchka; Nov 2, 2011 at 01:07 PM.
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From: Old Dominion
2015 VW GTI.S4; 2016 Audi Q3 Prestige
My vote also to the fuel filler door even though I mistakenly used the door jams rec on the way back from picking up the vehicle & drove 400 miles @ 35/39.
The dealer had given us a full gas tank so I wasn't even thinking about looking there for the contradicting info!
Ugg!
If you continue to read in the owners manual from pg 266-270+ they keep going back & forth on where to look between those 2 areas!
No wonder the wife complained the ride was rough! Eeeash.
The dealer had given us a full gas tank so I wasn't even thinking about looking there for the contradicting info!
Ugg!
If you continue to read in the owners manual from pg 266-270+ they keep going back & forth on where to look between those 2 areas!
No wonder the wife complained the ride was rough! Eeeash.
Last edited by MBNA109; Nov 1, 2011 at 11:49 PM.
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The TPMS has been one of the most annoying systems on the GLK. It's already back in the shop to have the module replaced for a second time.
I also hate the fact that the system only tells you that in general there's low tire pressure. Why can't it just show me which of the tires is below the threshold as oppose to me having to try and figure out which one(s) it is and then adding/removing air? It seems that most other vehicles will tell you the tire pressure in each individual wheel.
I also hate the fact that the system only tells you that in general there's low tire pressure. Why can't it just show me which of the tires is below the threshold as oppose to me having to try and figure out which one(s) it is and then adding/removing air? It seems that most other vehicles will tell you the tire pressure in each individual wheel.
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From: Old Dominion
2015 VW GTI.S4; 2016 Audi Q3 Prestige
Actually the exact statement in the manual on page 268 of the '11 manual is:
"The tire pressures in the tire pressure table on the inside of fuel filler flap are valid for all approved tires installed at the factory, unless stated otherwise."
"Tire pressure table for all approved tires installed at the factory"
Actually the exact statement in the manual on page 266 of the '11 manual is:
"You will find a table of recommended tire pressures on the Tire and Loading information card on the B-Pillar on the driver's side (>Page 274). You will find a table of tire pressures for various operating conditions on the inside of your vehicle's fuel filler flap."
So last I knew my tires were installed @ the factory. While the second statement above say to look in both places.
I am still
btw - The white label is next to the door jam label & basically repeats the black door jam label.
"The tire pressures in the tire pressure table on the inside of fuel filler flap are valid for all approved tires installed at the factory, unless stated otherwise."
"Tire pressure table for all approved tires installed at the factory"
"You will find a table of recommended tire pressures on the Tire and Loading information card on the B-Pillar on the driver's side (>Page 274). You will find a table of tire pressures for various operating conditions on the inside of your vehicle's fuel filler flap."
So last I knew my tires were installed @ the factory. While the second statement above say to look in both places.
I am still
btw - The white label is next to the door jam label & basically repeats the black door jam label.
Last edited by MBNA109; Nov 2, 2011 at 10:35 PM.
Super Member
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From: Old Dominion
2015 VW GTI.S4; 2016 Audi Q3 Prestige
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From: East Texas
2004 Volvo XC70; 2012 GLK 350 4matic
Dad was a man of few words. What he did say was rarely wrong. He coudn't fly B-52s and be wrong.
"Keep 35 pounds of air in your tires. The car will roll better and you'll get better mileage." He always carried a small notebook and recorded the miles and gallons of gas of every fillup. 35 psi may not be factory perfect for every tire on every car. It won't be far off. Better a pound over than a pound under.
That was Dad's way. It has worked for me since forever.
Wayne
"Keep 35 pounds of air in your tires. The car will roll better and you'll get better mileage." He always carried a small notebook and recorded the miles and gallons of gas of every fillup. 35 psi may not be factory perfect for every tire on every car. It won't be far off. Better a pound over than a pound under.
That was Dad's way. It has worked for me since forever.
Wayne
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From: Old Dominion
2015 VW GTI.S4; 2016 Audi Q3 Prestige
Just one more data point added to the confusion & a direct contrast to what MBUSA said to me on the phone - this from Dunlop/GoodYear:
to me
Sent by: Goodyear Tire & Rubber Company Consumer Relations 728 1144 East
Market Street Akron, OH 44316 Voice #: 800.321.2136 Fax #:
330.796.6829
Operating air pressure is determined by the vehicle manufacturer.
The proper air pressure is indicated on the door placard or owners manual
of your vehicle.
The air pressure indicated on the sidewall of each tire is the inflation
pressure required to carry the maximum allowable load for that tire.
Vehicle manufacturers have invested considerable time and testing to
establish an air pressure that will provide a smooth comfortable ride in
addition to an even tread wear pattern.
The 2011 Mercedes GLK 350 4Matic (20" Tire Opt.) comes original with a
235/45R20 100H, it is recommended by the manufacturer to run the fronts at
35 psi and the rears at 39 psi.
Daniel T. Gibbs
Consumer Relations
to me
Sent by: Goodyear Tire & Rubber Company Consumer Relations 728 1144 East
Market Street Akron, OH 44316 Voice #: 800.321.2136 Fax #:
330.796.6829
Operating air pressure is determined by the vehicle manufacturer.
The proper air pressure is indicated on the door placard or owners manual
of your vehicle.
The air pressure indicated on the sidewall of each tire is the inflation
pressure required to carry the maximum allowable load for that tire.
Vehicle manufacturers have invested considerable time and testing to
establish an air pressure that will provide a smooth comfortable ride in
addition to an even tread wear pattern.
The 2011 Mercedes GLK 350 4Matic (20" Tire Opt.) comes original with a
235/45R20 100H, it is recommended by the manufacturer to run the fronts at
35 psi and the rears at 39 psi.
Daniel T. Gibbs
Consumer Relations
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From: East Texas
2004 Volvo XC70; 2012 GLK 350 4matic
Does this help at all? From an interactive online MB GLK owner's manual. They mention the filler flap information as the last word.
Tyre pressure specifications
You will find a table of tyre pressures for various operating conditions on the inside of your vehicle's fuel filler flap.
Operation with emergency spare wheel: The applicable value for the emergency spare wheel is stated on the spare wheel and in the technical data section.
Operation with a trailer: The applicable value for the rear tyres is the maximum tyre pressure value stated on the table inside the fuel filler flap.
The table inside the fuel filler flap may state tyre pressures for different load conditions. These are defined in the table as different numbers of passengers and amounts of luggage. The actual number of seats may vary - for more information please refer to the vehicle's registration documents.
If no other data is stated, the tyre pressures specified on the fuel filler flap apply for all tyres approved for this vehicle.
If a tyre size precedes a tyre pressure, the tyre pressure information following is only valid for that tyre size.
You will find a table of tyre pressures for various operating conditions on the inside of your vehicle's fuel filler flap.
Operation with emergency spare wheel: The applicable value for the emergency spare wheel is stated on the spare wheel and in the technical data section.
Operation with a trailer: The applicable value for the rear tyres is the maximum tyre pressure value stated on the table inside the fuel filler flap.
The table inside the fuel filler flap may state tyre pressures for different load conditions. These are defined in the table as different numbers of passengers and amounts of luggage. The actual number of seats may vary - for more information please refer to the vehicle's registration documents.
If no other data is stated, the tyre pressures specified on the fuel filler flap apply for all tyres approved for this vehicle.
If a tyre size precedes a tyre pressure, the tyre pressure information following is only valid for that tyre size.
