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BMW 3-Series Run Flat Tires

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Comments

  • boston303boston303 Posts: 35
    Well, if someone informed you that the tires cost twice as much as other GF high performance tires and that they only last 30% of the life of GF tires I think that equates to a muiltiplier of 6 times more expensive than normal tires.. That wouldn't cause you a double take? I suggest few buyers had any clue of the poor performance and true expense of these tires. Shameful of BMW. Add to that BMW's insistence that you cannot replace the tires with normal go flats and again we have a car once heralded as the Ultimate Driving Machine being relegated to simply just another car with an tires that do not perform particularly well (I will except "M" series) and served up with an automatic transmission for drivers who would prefer to choose a car for it's color and not its performance elements. I know of many people who have purchased a car but had tires swapped out for another choice. Unfortunately that is not a true option with BMW. "Bimmer's" have gone to the "Beemer" crowd I fear...
  • shiposhipo Posts: 9,152
    "I know of many people who have purchased a car but had tires swapped out for another choice. Unfortunately that is not a true option with BMW."

    Why is it not a "true" option? Simply yank the RFTs and wrap on a set of GFTs the day you bring the car home. If the car is leased, store the RFTs until lease end and put them back on. If the car is purchased, peddle the RFTs on Craig's list and be done with them. :confuse:
  • MrShift@EdmundsMrShift@Edmunds Posts: 43,640
    This might be somewhat relevant...I was reading about the history of bicycles, which of course had a tremendous influence in America on the history of the automobile (bikers demanding better roads, bike manufacturers becoming car manufacturers, etc) and I read that when pneumatic bicycle tires came out, the switchover from hard rubber tires was almost immediate. In a couple of years, the rubber tire was dead, dead, dead.

    I'm sure not seeing this with RFTs. If there is an "improvement" over GFTs (debatable), then it is incremental at best.
  • shiposhipo Posts: 9,152
    "I'm sure not seeing this with RFTs. If there is an "improvement" over GFTs (debatable), then it is incremental at best."

    Let's see, in exchange for being able to drive (and potentially ruin) an RFT following a pressure loss event (both a positive and a negative), you get a tire which is heavier (a negative), rougher riding (a negative), louder (a negative), and with a shorter tread life (a negative). I'm not seeing the attraction. :)
  • busirisbusiris Posts: 3,445
    You should really get your facts straight. There is absolutely ZERO requirement from BMW that any owner stay with RFT's.

    I understand you dislike RFT's to the max, but you really don't seem to know much about them or BMW (can't repair RFT's, can't replace them with GFT's, etc).

    In fact, you seem to have a general dislike of BMW in general.

    Or, anyone who doesn't share your opinion of the company.
  • MrShift@EdmundsMrShift@Edmunds Posts: 43,640
    Well that's not *entirely* true, because if you leased a BMW with RFTs, I believe the leasing company would require that RFTs be on there when you return the car.

    To give you an idea of how desperate BMW/MINI owners are:

    image
  • capriracercapriracer Somewhere in the USPosts: 785
    If you want to convince BMW abot RunFlat Tires, you need to get in sync with their thoughts or they will ignore your input:

    RFT are more expensive. BMW would agree with that.

    RFT ride harsher. BMW would agree with that

    But BMW would not agree that RFT are noisier - in and of themselves - they can be made to be quiet just like GFT.

    And BMW would not agree that short treadlife is a property of RFT. They can be made to wear as well as GFT.
  • shiposhipo Posts: 9,152
    While BMW might well believe RFTs can be made to last as long as GFTs, the current crop of tires on the market suggests otherwise. How? The highest UTQG rating I can find for an RFT in a size which would fit a late model BMW is 400, that said, there are many GFTs in that same size which score 500 or better, 600 or better, and even a few which score 700 or better. Not exactly a ringing endorsement for the lifespan of RFTs. :P
  • capriracercapriracer Somewhere in the USPosts: 785
    But there are GFT tires with lower ratings than RFT, so what does that prove? You need to compare apples to apples. If you compare like tires, you'll find they have the same UTQG rating in both GFT and RFT:

    Examples: BS RE050A 140 A A, Michelin PS2 220 AA A, Pirelli PZero 220 AA A, Yoko Advan Sport 180 A A..... OK I'll stop now, but you get the idea.

    There is nothing inherent in a RFT that affects the wear qualities.
  • MrShift@EdmundsMrShift@Edmunds Posts: 43,640
    Well when I saw all four RFTs on my friends 2007 BMW 328ix melt before our eyes at 18,000 miles, I had to think something was up that was not mechanically related.
  • shiposhipo Posts: 9,152
    Hmmm, I'm thinking we're going to have to agree to disagree. My personal belief is that even though there are two tires called say "Michelin PS2", one in RFT form and one in GFT form, those two tires are essentially separate and distinct. True, they may have a similar or even identical tread pattern, but the carcasses of the two tires are completely different as are the driving characteristics.

    From my perspective, it is just as valid to compare tires from different manufacturers (or even different models from the same manufacturer) for tread life once you distinguish between RFT and GFT types.
  • busirisbusiris Posts: 3,445
    Well that's not *entirely* true, because if you leased a BMW with RFTs, I believe the leasing company would require that RFTs be on there when you return the car.

    Yes, a leased car usually must be returned in the condition in which it was leased, less reasonable wear-and-tear. However, nothing in any lease I have ever seen even suggests that RFT's can't be replaced with GFT's, just as long as the car is returned with like-original equipment tires on it.

    While I understand what you are saying here, it really doesn't apply to any BMW policy regarding the requirement of RFT's on its vehicles. The choice of GFT's or RFT's are entirely up to the owner/lease holder, and no warranty issues are tied to the use of non -OEM equipment tires, as long as the tires are reasonably sized for the car.

    Off hand, I know 4 BMW/MINI owners who have moved to GFT's with no reactions from BMW or MINI.

    After all, doesn't the M3 come with GFT's and a patch/plug/repair kit?
  • cdnpinheadcdnpinhead Forest Lakes, AZPosts: 3,206
    . . . no warranty issues are tied to the use of non -OEM equipment tires, as long as the tires are reasonably sized for the car.

    While what you say here is entirely accurate, there are numerous reports of BMW dealers telling people that replacing RFTs w/ GFTs will "void the warranty" and/or that it "can't be done."

    Balderdash for sure, but it does happen.
  • busirisbusiris Posts: 3,445
    Oh, I'm sure it happens...

    But then again, there are dealers across the spectrum of manufacturers that tell owners having a non-dealer entity service their car (or even perform an oil change) will void their warranty.
  • kyfdx%40Edmundskyfdx%40Edmunds Posts: 25,879
    Leased BMWs that come with run-flats, have to be returned with run-flats...

    Moderator - Prices Paid, Lease Questions, SUVs

  • busirisbusiris Posts: 3,445
    edited July 2011
    Leased BMWs that come with run-flats, have to be returned with run-flats...

    I think everyone is in agreement with that statement.

    The specific question at hand was whether or not a lease-holder could swap the RFT's out for GFT's and run GFT's during the term of the lease, then return the car with the original RFT's re-installed (or a tire like the OEM RFT's). And the answer to that question is a definite "yes".

    As in any lease, the car is to be returned at lease-end in the delivered condition, minus accepted wear and tear.... unless wording in the lease specifies otherwise.

    There is no prohibition against running GFT's on any model BMW sold in the USA (at least, none that I am aware of...).
  • capriracercapriracer Somewhere in the USPosts: 785
    Shipo,

    You may have inadvertently gone somewhere where we have an agreement!

    The RFT's we are discussing have 2 common characteristics - aside from RunFlat capability: They are high performance tires and they are OE (Original Equipment) tires.

    High performance tires are noted for their grip and they do this by sacrificing treadwear - and this is a common complaint about HP tires.

    OE tires are designed to the vehicle manufacturer's specs and that usually puts an emphasis on rolling resistance, and that is done by sacrificing treadwear and/or traction - and clearly traction is not one of the options in a BMW! Treadwear is a common complaint about OE tires.

    So it should be expected that OE HP RFT's - like the ones we are talking about - should have some complaints about treadwear - simply because they are OE and HP.

    Further, we should expect tire manufacturers to do something different for their OE tires to get them to have better RR - and that was where you wound up - a separate and distinct tire for each OE application - and that would include the tires under discussion.

    Further, the "separate and distinct" part would apply to both GFT's and RFT's - which muddies the waters even further - making separating out what is causing what very difficult to get a grip of.

    We know that OE GFT tires sometimes have wear issues and we know that replacement market GFT's generally don't. We also know that OE RFT's sometimes have wear issues, but what we DON'T know about is replacement market RFT's (at least ones designed for good wear qualities!) So while we agree that the tires under discussion are separate and distinct, we disagree over what is causing the wear issue - and we are missing some information that would be very helpful in sorting this out. We need to approach this problem from a different angle - and I would suggest we look at how these two types of tires are designed.

    The one over-riding design feature in a RFT is that there is something in the sidewall that greatly stiffens it. This certainly has implications on ride qualities and cost, but there doesn't seem to be a connection to treadwear. Wear rate is pretty much determined by the tread compound. And since rolling resistance, traction, and treadwear are affected by the tread compound, this would account for the differences seen in GFT's. That principle shoudl apply top RFT's as well.

    There are a lot of things that would adversely affect treadwear, but there is no inherent characteristic of RFT's that precludes good wear.
  • busirisbusiris Posts: 3,445
    There are a lot of things that would adversely affect treadwear, but there is no inherent characteristic of RFT's that precludes good wear.

    Disclaimer: I am not an automotive tire engineer, so this is only an observation...

    A tire maintains traction (grip) by several factors, including tread rubber compound, tread design, and flexibility.

    Inherent in that flexibility characteristic is sidewall "mobility". For example, one would expect to see better traction (and, by default, the ability to go at a faster rate of speed in making a circle) in a car equipped with a modern GFT (say 185/75 R15 sized tire) than the same diameter wheel surface that only had 1/2 inch of rubber surrounding the outer surface of the wheel.

    Why? Because we live in an imperfect world, and there are no uniform surfaces, so the tire surface must continually modify its section that is currently meeting the road surface.

    So, it would seem to me that sidewall stiffness does indeed play some part in traction, and in that regard, the easiest way to enhance traction is to use a softer rubber compound, which in turn, usually translates into less tread life.

    Now, as to what that differential might be, I couldn't say.

    But, I suspect that is the reason some RFT owners can get virtually the same mileage out of a set of RFT's as GFT's, because they don't get anywhere near pushing those limits (my wife and her MINI fit in this category, and she easily got 50K out of her OEM RFT's)....whereas, other RFT owners are more "spirited" drivers, and often have a driving style that enters that realm of traction "testing".

    Just my opinion and observations.
  • shiposhipo Posts: 9,152
    edited July 2011
    I managed to get more than 50,000 miles out of the OEM All-Season GFTs with a 400 UTQG which came on my 328i (and I never took it easy on those tires). Granted this is going back to before the RFT issue ever reared its ugly head, but not all OEM tires suffer from limited tire wear.
  • busirisbusiris Posts: 3,445
    ...not all OEM tires suffer from limited tire wear.

    I agree, but it can appear to be model-specific.

    For example, I have a daughter that has a 2008 Nissan Altima which came equipped with Continental Conti Pro Contact tires. After almost 40K miles, there is excellent treadlife left.

    My other daughter owns a 2009 Nissan Versa with the same tires (different size) and the tires were almost bald at 35K miles.

    Both cars were purchased new, and neither daughter is an aggressive driver. The only significant difference that I can identify is that the Versa went on a cross-country trip and back whereas the Altima didn't.

    Beats me why the same tire had such different wear results on the 2 cars...
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