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Yet another GLK250 Tire Question

20K views 37 replies 11 participants last post by  Dietmar 
#1 ·
Hi all,

Just purchased my first Mercedes. Have owned multiple Porsche, Audi and BMW vehicles so looking forward to seeing how I will like the GLK over the long term (hopefully a lot!). However I have a question for this group. I have a 2014 GLK250 with the AMG style option with the Dunlop GrandTrek Touring AS MO tire. So a few questions. First is it definitive or not whether these tires are run flat (or even the Mercedes limited version of run flat)? My dealer said they are (run flat), but I'm not convinced. Second...I know this is a special tire for Mercedes from Dunlop however when looking at the Dunlop site it states that all GrandTrek Touring AS tires are all season. That's fine, but my tires actually have the winter symbol on them (snowflake inside of the mountain) indicating that these are in fact winter tires. Anyone else have these as well? I've sent an email to Mercedes for confirmation, but this would be the first time I've ever purchased a vehicle and have it come with winter tires and not all season or summer tires. As I live in a ski town I'd really like to confirm what the heck these tires are truly rated for. Thanks for any input.
 
#2 ·
Hey ... Welcome ... I hope you like your new ride!

the designation MO means Mercedes Original, NOT extended mobility ... which would be MOE.

If you have a Canadian spec GLK, there should be a can of gunk and a compressor in the tool area and behind the left rear light panel.

In Canada the snow flake in the mountain means WINTER tires, not all season. You'll need 'em in Whistler anyway.

Drive safe ... and do a drop off the Peak for me :)
 
#3 ·
Thanks fcch!

That's what I thought. Never trust a dealer. If I had gotten a flat and driven that would have killed the rims. S'funny I actually would have preferred for the tires to be all season as I would have then purchased 17" rims and winter tires. I now have 20" winter tires, which if I want to use means I will have to buy 20" rims (would prefer not to use the AMG rims in the winter). I guess I could still buy 17" snow tires and use these ones for summer. Being snow tires they should just be softer and wear down a bit quicker in the summer.

Thanks again!
 
#5 ·
My GLK came with the Pirelli Scorpion zero tires, which are all seasons, but also have the snowflake symbol.
That means that they have a snow rating, and would be adequate for light winter conditions, but they are by no means winter tires.

You will find several opinions here on the stock GLK tires, where some people say they are good enough in the snow, and some people say they are useless, and they go for a set of snows in the winter.

I personally, have a set of 18" rims with 235/55R-18 Bridgestone Blizzaks, and that works well for me.. specially driving back and forth to Whistler for skiing.

The 20 inches Pirellis (I also have the AMG rims), are not used in the winter, even with the snowflake rate.
 
#6 ·
Hey mtbmarc,

Thanks. My thoughts exactly...not even sure why these have the snowflake symbol when the standard Dunlop GrandTrek Touring AS tires don't. Anyhow totally agree on getting new rims and real snow tires. Getting pricing right now on a few options on the recommended 235/60/17 size. I've had the Nokians on one of my Audi's and loved them. The last ones I had were Toyo Gsi5...they were pretty good, but not great. I'll look at the Blizzaks as well. Nice to know they are working out well for you on your drives to Whistler...although perhaps this year hasn't been the best test!

Let's hope for our usual snow dump in Feb/March. cheers!
 
#7 · (Edited)
It is weird that they have the snowflake ... especially if it is inside the mountain icon. ... Whenever the indication is M+S (Mud and snow) ... they are NOT winter tires.

I have the Nokian SUV 7 but they are studded 235/60 R17. With RSSW rims it was half the price that the dealership was asking for their "winter package".

Love 'em.
 
#8 ·
Yeah the whole thing with the tires has been weird. For my first Mercedes I'm loving the vehicle, but once again the dealership is leaving me less than impressed. Why is it that the customer always knows WAY more than the dealership? Anyhow totally agree on loving the Nokians and it's the way I'm leaning. And like you said pricing is coming in anywhere from 33-50% cheaper than the dealer. Heck if I wanted to pop across the border it would be quite a bit cheaper than that even with the tanking loonie. Thanks for all of the comments all.
 
#10 ·
Hey fcch!

Yep do realize that we don't get a TPMS. I actually would have liked it as I have them on my Sprinter and it's really nice to see the actual pressure for slow leaks. Still it is nice to save the money on the new tires!

So now I have another favour to ask of you. Can you please send some of your snow this way!

cheers.
 
#13 ·
I know little about cars but hope by posting the information about my tires, I can get some advice from you the knowledgeable fellow members. The GLK 250 was delivered to my wife in late January (for convenience, I will call it my car here). We are in BC, Canada. The car was apparently manufactured in Nov 2013 as the label on the door sill said 11/13 among other things. I know that cars made in other periods of time may have other tires.
The tires are marked: Continental Contact 4X4 235/50R19 99H M+S Radial Tubeless MO.
I see that on the speedometer screen (when I use the small arrow and OK buttons to make the "tire pressure" monitor information appear) says something like "runflat". I guess it means when I see the "runflat" warning appears on the road, at least one tire has lost pressure and I will need to deal with that. There is also a "restart" function for use after any changing/fixing/rotating/pumping/re-fitting of the tires.
Intuitively I don't think I have runflats and searching for information on the internet tends to confirm that, so I tried to search the manual but it generically described all types of tires available to different kinds of GLKs in the US and Canada. So I could not find the relevant information I wanted. To make it even less clear, when asked, the Mercedes sales and service people have told me that the tires were runflats.
I don't mind runflats or non-runflats but I need to know why the tire pressure monitor screen on the speedometer says "runflat" with an option to "restart" whilst information available tend to indicate that I do not have runflat tires. I wonder if a tire pressure monitor intended for runflats can monitor the pressure of non-runflats (that I probably have) accurately.
Can anyone please kindly shed some light on that?
 
#14 ·
Hi NSW,

Well from on BC person to another I can say my dealer experience has not be great and it's only through the forum here that I got my answers. So I'll try to at least clear a bit of it up. The tires you have are MO tires, which means that they are Mercedes approved, but NOT run flat. To be run flat it would have to say MOE or have SSR on the sidewall as well which is Continental's marking for run flat tires. Here is a link to the specs for Continental tires: http://www.continental-neumaticos.es/www/download/neumaticos_es_es/temas/consejos/databook_es.pdf

You can scroll right to the very end of the document for the footnotes to see the MO and SSR designations.

As far as I know the Canadian spec GLKs don't have a true TPMS system. Meaning they don't monitor the exact pressure in each tire, but they do have a sensor that monitors rotational speed so if you get a major flat they will let you know.

You should have, in the back of your vehicle on the left hand side, a can of sealant and an electric pump to seal small slow leaks.

I'm not sure why you have "run flat" showing up on the screen (I'm not at my vehicle right now so I can't check mine), but perhaps it is just a selection to choose IF you do have run flat tires. Perhaps someone else on the forum can shed some light on this, but I'll check my vehicle tomorrow.

Hope that helps a bit!
 
#15 · (Edited)
Thank you so much Guitarick for responding!
I have checked out the PDF file linked to in your post and now thanks to you I know that there are MO and MOE tires. Perhaps that is it but still I think if Mercedes wants to dictate a set of specifications to a tire maker, may be a little bit, not a lot, of run flat ability can possibly be included. Otherwise, why not just buy normal Continental tires or other makes. So the MO tires may have just a little bit of run flat capability but still affords the people in the car a comfortable ride whilst the MOE tires may have more run flat ability but can provide less comfort. Ultimately, the SSR tires may be the true runflats. Different degrees of runflat ability are required/permitted by law in different places:). Continental seems not to have made what is meant by MO/MOE very clear. They just more or less say MO means Mercedes specifications and MOE means Mercedes Specifications (Extended). It is open to us to interpret that MO tires still have a little runflat ability though less extended. But please do not believe me. We may need to find out a clear cut answer. It is about safety. Please note that I am not arguing with you. You are just being helpful but I am trying to give my tires (and the Mercedes sales and service people who have told me that they are runflats) some benefit of doubt.
As for getting to the tire pressure monitor, you can use the 4 arrows with the OK button in the center at the left side of the steering wheel to achieve that. Please try the left/right pointing arrows first until you see the page that contains the words "tire pressure" and then use the up/down arrows to move a line that appears there to just below "tire pressure" and then press "OK" and you will see what I mean. You will have to do that when the key is turned a notch or the keyless start button is pressed once/twice (do not step on the brake to avoid starting the car) without actually having to start the car.
It is late now but may be tomorrow I will try to find the bottle of sealant from the trunk as advised by you. I doubt my wife will like to use it in case of a flat tire. Her first reaction may be to park the car and call Mercedes Road Side Assistance or BCAA.
Lastly, IIRC, I have not seen any description of "MO" in the manual. "MOE" has however, been mentioned and explained. I think that is bad but this does give me a little bit of room to imagine that may be MO is just a lower grade of MOE. Wishful thinking ;).
Thank you again fellow BC resident!
 
#16 ·
NSW,

So the MO tires may have just a little bit of run flat capability
...

Sorry no. The MO Continentals do not have any runflat characteristics.

As for the can of sealant, it is kinda hidden behind the small panel in the rear left side. It's the small panel you would use to access the wiring for the left rear tail lights.

Hope you like your GLK :)
 
#17 ·
I can confirm what fcch has said - In Canada, the MO tires we get are not run-flats. And the GLK250 has no spare (The GLK350 does). In Canada we do get a compressor and a can of sealant.

The MOE tires that they get in USA are not really runflats either, but they can be driven short distances when flat. But not as far as true run flat tires.

When I bought the GLK250, both the dealer and I thought we were getting run-flats. I ended up buying a spare.
 
#18 · (Edited)
Thank you gentlemen! I think you are right. I am fine with either runflats or non-runflats as long as I am sure about what I am having. I have found the pump in the trunk but I am yet to locate the sealant. Perhaps I have none. I will try again tomorrow.
Here are some pictures for your reference. They are self explanatory but some have served an unintended purpose of misleading me. In one of the pictures, you can see the pump and a jack (I do not have a spare!!) LOL.
Thanks again. This board is good!

Edit: Just found the sealant in its "hidden" place. Hope I will not have to use it. It does not seem easy to use to me anyway.
 

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#22 ·
Thanks for your post ronwp! I have read the corresponding page (P.359) on my manual and am now quite sure that the tires on my wheels are not runflats.
Well, at least they will last longer and are cheaper to fix when "nailed". Presumably they will also provide a more comfortable ride. So I am fine with them.
However, I hope my suspension is not tuned originally for MOE tires (I worry because my car does have an operative runflat indicator (monitor) and its counterparts in the US do have MOE tires) and thus will provide a not so good ride and worse handling when matched to my present MO (instead of MOE) tires. I must say I do not understand why Mercedes have made me pay for the runflat indicator but does not let me have MOE tires.
Having said that, I believe my tires will have enough "crawl flat" ability, say for may be up to several meters at slow speed, to let me park the car safely to wait for roadside assistance whenever a loss of pressure is detected :).
 
#23 ·
Go to page 337, You will see:
Tire pressure loss warning system
(Canada only)
General notes
While the vehicle is in motion, the tire
pressure loss warning system monitors the
set tire pressure using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tire. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appear in the multifunction
display.
You can recognize the tire pressure loss
warning by the Run Flat Indicator
Active Press 'OK' to Restart message
which appears in the Service menu of the
multifunction display. Information on the
message display can be found in the
"Restarting the tire pressure loss warning
system" section (Y page 338). :)
 
#24 · (Edited)
I understand what you mean Ronwp and appreciate your advice.
I think Mercedes could have avoided misunderstandings by using another name for the Run Flat Indicator. They can call it tire pressure monitor or something similar. See the pictures attached to my post on 2 - 4 -14 (#18) please.
Imagine someone renting/borrowing a 2014 GLK 250 in Canada, drives it and perhaps suddenly gets a MO tire damaged by a nail on the road, then he will see a warning signal from the "Run Flat Indicator" appearing on the speedometer screen. He may be led to think "so this car has run flat tires and it is OK to drive on for a while". In fact, the car does not have MOE/run flat tires and the wheels may be damaged and an accident may be caused if he drives on. It is something that no one would like to see.
It is now settled that I do not have run flat tires. I am fine with that and do enjoy having tires that probably have a longer life and a more compliant ride. I just think Mercedes should have "come clean" about that (one can see from the above that there are other posters who have also been once led to believe that their cars came with MOEs/run flats whilst in fact their cars only have MO tires).
Just my humble opinion, and thank you again.
 
#25 ·
Isn't Canadian MO rated 50 miles under 50 mph like US ?

MOE gives better ride than "run flats" but here in the US MOE 50 miles not 200 miles like run flat - but both those mileage ratings are kindof a cruel joke since man you will really know when either a MOE or run flat are without air.
 
#27 ·
Really appreciate your response fabbrisd1. Thanks to ronwp (please see his post above), now I am aware that P.359 on our manual can confirm that only MOE tires can run flat. MO tires have no run flat ability (at least there is no indication, on that page of the manual, that they have such ability).

I agree that a driver may still know when a MOE/MO tire is running without air pressure even without a warning system. Perhaps the car's automatic warning system can either produce an earlier (than human detection) alarm or confirm what a driver may suspect under some circumstances. I just think that Mercedes should have avoided using words like "run flat(indicator)" in the warning system when the cars do not come with tires that have any run flat characteristics. This (that those words are still used anyhow) have led me to think that may be the MO tires are not different from MOE tires but are prevented from being called MOE(E = extended) in Canada because of local laws. See also next para. for more explanation why I think so. Disclaimer: I would guess that 99.999% I am wrong.

Just my wishful thinking, may be MO tires do have a little little bit of run flat ability but may be due to that the run flat ability is so limited (e.g. not significantly better than ordinary tires), the local laws where the cars are sold prevent the manufacturer(s) from claiming the they are run flats of any kind. I must repeat and emphasize that this is only my wishful thinking and can most unlikely be true. Anyway, the MO tires are OK to me as they come with a repair kit. The kit is better than a spare when there are multiple nails on the road which can damage more than one tire at one time or during one trip. Talk about positive thinking :). The MO tires may not be run flats but they are cheaper to replace/repair and should presumably provide a more complaint ride. So, I am still happy.
 
#26 ·
nsw, the best practice is to conduct regular physical confirmation of your GLK's tire pressure using a tire pressure gauge. I keep a separate pressure gauge in each of my cars and check the tire pressure regularly. As the outside temperature changes, the tire pressures can change a fair bit, so keeping the pressures up to specification on a regular basis is a good thing. As well, you should reset your run-flat indictor system after re-setting your tires' pressures. This step is forgotten by many. Doing so re-aligns and re-calibrates the monitor to the proper set-point.

The concern (or more like a warning or something to be aware of in the back of your mind) with an ABS-based run-flat indication system is that it can take a significant pressure loss in a tire to trigger the flat-tire warning. Because it it not a direct pressure reading system, there is not a specific 'pressure-loss' set point that will trigger a warning -- it will be a % rotational speed difference. The tire's design and configuration/size will affect how much it deforms with pressure loss, and thus how much pressure loss it will take before triggering the system warning. With such a system, a lower-profile, more rigid tire will likely result in a greater pressure loss before triggering the warning that perhaps a taller, more compliant tire would.

As far as I know, all the German manufacturers use this method in Canada, my 335d has a similar ABS-based 'flat tire monitor' and I've had warnings being indicated at pressures (checked by a tire gauge) ranging from a just a few (6-7) PSI low, to a significant difference (~20 PSI low). In fairness, the BMW system's warning was yellow for the small loss, and red for the greater loss, so it did indicate the severity of the loss. I am not sure how the MB run-flat indicator warning would be presented, but the point being that depending on the characteristics of the tires mounted on your vehicle at the time, you may receive a warning when there is notably more pressure loss than a direct pressure reading TPM system as used in the US.

That said, I hope you are enjoying your GLK 250 as much as my wife and I are.

Regards
D.
 
#28 ·
I must thank the OP for starting this thread so that I can read such valuable advice/explanation from you. I will remember to manually check the tire pressure periodically for safety.
Yes, my wife and I are enjoying the GLK 250. Apart from an apparently smaller trunk than the 2009 Toyota Matrix that it has replaced, the GLK is a good easy to drive car. It will be kept for long, very long. The Toyota does have an advantage though (sorry to go off topic, but when talking about whether I enjoy the GLK, I have to compare it to other cars). I have once travelled and left it (Toyota) in the garage for 4 months. It started at once without fuss when I returned home and turned the key. The E Class (my other car) on the other hand, required to be helped by a neighbor with a jump cable. Now back to topic....;).
Thank you very much for taking the time to respond to my post. This is a very useful board with so many knowledgeable and helpful members.
 
#29 ·
Please forgive me for asking one more question :). Please read on if you do not feel bored and do like sleuthing ;). I know that the GLK 350s in Canada do not have the same tires as the GLK 250s (again in Canada). They have a set of superior regular tires (Pirelli?) and a donut spare but have no repair kit (please correct me if I am wrong). My point/question is if a set of regular tires with no run flat characteristics (now we seem to believe that are what the MO tires are) plus a repair kit is good enough, why can't the 250s have the same tires as the 350s considering that the 250s do actually already have the repair kit to compensate for the lack of a spare tire? I think this bespeaks that the MO tires that the 250s are equipped with do have some additional characteristics (when compared to the standard tires on the 350s) in order to compensate for the lack of a spare. May be without those additional characteristics, even having a repair kit is not enough. I wish someone could enlighten me as to what do the MO tires have that the standard tires on the 350s do not. I know there must be someone who knows out there.

PS: I have verbally asked the service people of the Mercedes dealer who I usually use to give me a definitive answer as to what the MO tires are, limited run flat, or the like, or not. I am yet to receive a reply. I am afraid that I may not get an answer at all. May be in a few years when it is time to replace the MOs, I will ask if I can buy the tires currently used by the 350s for putting on my 250 and see what the service people will say. After all, if the standard tires on the 350s are less expensive (but possibly have better ride and handling characteristics), I do not see why I cannot buy them for my 250. The repair kit is there in case I get a flat and need a fix on the road anyway:).
 
#33 ·
I will ask if I can buy the tires currently used by the 350s for putting on my 250 and see what the service people will say. After all, if the standard tires on the 350s are less expensive (but possibly have better ride and handling characteristics), I do not see why I cannot buy them for my 250. The repair kit is there in case I get a flat and need a fix on the road anyway:).
The manual gives the specs for tires. It shows same tire specs for 350 and 250, except in USA for GLK where MOE tires are specified.

The MO only indicates that the tires were built to Mercedes specs. Nothing to do with runflat capability. They have none. Just designed to match the characteristics of the suspension.

There are many here who have put standard snow tires on their GLK 250/350s and these are not MO tires.

Whether the Conti MO tires are better or worse quality than the Pirellis? Who can say? Just like for snow tires, I suspect any standard tire would be satisfactory although perhaps not quite as well matched as the MO tires.

Can anyone who has a 2013 or 2014 GLK350 confirm whether or not the original tires are MO or not?
 
#30 ·
I have 19" MOExtended MS all season with snow flake and a direction of Travel Arrow.
Because MB wanted a smoother riding run flat tire it does not meet international criteria /definition of a Run Flat... Hence MOE label. They are Modified Run Flats.
The arrow indicates the forward direction of travel ...so when rotating these tires the arrow(s) must point forward rotation. Just had mine rotated 5k miles front to back, back to front at a local shop. When 10k I'll have it done at my dealer. 2013 GLK 250

See link MOExtended tires (tires with run-flat properties) - Flat tire - Breakdown assistance - Mercedes-Benz S-Class Owners Manual - Mercedes-Benz S-Class | MercedesManuals.org
 
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