Seeking advice/experience on run-flat tires

I’m curious about run-flat tires for my pickup truck and trailer.

Summary: After a highway blowout* on a trailer tire, I was thanking various deities it happened near a freeway exit. Just prior, we had been in a single lane construction area for many miles. I shudder to think how much worse it would have been to either stop near speeding traffic, or continue many miles on a shredded tire to reach safety. Even our quick stop failed to save portions of the wheel wells from damage as the tread flopped around the inside. In addition to the tire, we had body damage to repair. As I understand them, run-flat tires will hold together, and allow you to continue at reasonable speeds for many miles to reach a safe area or even a shop.

So I’m considering them for both the truck and the trailer, but wanted to ask for advice here. Some websites claim the “ride” is worse on those tires, but I’m wondering if it would be an issue on a 3/4 ton truck (the tires are already at 80 lbs pressure – it rides rough already).

So my questions to those who have used, or have knowledge about run-flat tires:

  1. Is there a considerable difference in either ride, handling, or noise?
  2. Do they actually work as advertised (ability to drive 20+ miles to repair at reasonable speeds)?
  3. Do they last as long (miles) as typical tires?
  4. Are there other issues I haven’t thought of? (Must all 4 tires be run-flats, or can a normal tire replace one of the r-f’s for a time? Are there issues with the existing TPMS systems?)

*Later determined road debris and damage were the cause. With the deteriorating condition of many US highways, I expect this may continue to be a problem.

I am not a tire expert. However, We do have run-flats on my wife’s car.
Tire noise is higher.
Handling is a fit different, but within the variance for any new set of tires.
We like them. Fortunately we haven’t had and flats in that car. The only flat recently was when she was driving my car. Sigh.

The only thing I know about run flat tires is that most BMWs come from the factory with them, and many owners hate them.

Excellent intro there @Crafter_Man! Thank you. :wink:

I have run-flats on my BMW. Very low profile Pirelli P-zeros. So a very different mission from a pickup truck or trailer. What follows may be more or less useful for that reason.

The run-flats work well for low air pressure situations. Handling is essentially normal at zero air pressure. My tires are rated for something like 100 miles at 50mph when dead flat. I’ve driven farther & faster than that on one that was already out of tread and I knew would be replaced not repaired once I got to the shop. Wear & handling was normal while flat. I would not have been up for driving aggressively on it, but I could drive in an ordinary sane manner with no handling concern.

Road hazards like nails, screws, etc, into the tread can be plugged & re-inflated just like an ordinary tire. Balancing and mounting is no different than a similar non-runflat low profile tire

The tire is just as susceptible to sidewall damage, blow out, or tread separation as an ordinary tire. What’s different is what happens next.

They run normally with a big sidewall cut that deflates them. I’ve had that happen on Miami’s junk-littered freeways at speed and except for the loud bang! it was a complete non-event. I thought I’d just hit some debris. It was only a few seconds later when the TPMS complained that I knew I had a dead tire. The sidewall gash was big and the deflation was instant. The car didn’t wiggle a bit.

I’ve had a tread separation on an old runflat that was on a car that had sat for years in storage. So lots of age and little mileage used; that’s not good for a tire.

So there I am going about 80mph and bang! The handling was as above: a non-event. The loose tread flap made a lot of noise and did some minor damage to the wheelwell liner as I slowed. Once stopped I inspected it, razor-knifed off most of the ~3"x6" loose tread flap and drove the massively unbalanced totally flat tire ~15 miles down the freeway shoulder at ~20mph then a few miles of surface streets mixing normally with traffic to the nearest tire center. Of course this happened on the interstate well out into ruralia, not in town. Again a non-event overall.

None of these events has resulted in wheel damage.

Given the size of my trunk there’s simply no space for a spare. Hence the factory run-flats. I’ve not tried fitting non-run-flats, so I can’t compare the handling exactly A for B on this particular car. But I’ve been driving sports cars aggressively now for 45 years and gone through a metric boatload of high speed tires by every performance brand you’ve heard of. These tires grip better, handle better, etc, than any earlier generation non-run-flats. If they are giving up something for their run-flatness, it can’t be much.

The only downside I can see is they cost extra, and P-zeros specifically don’t last many miles, but for both your and my very different missions it’s still the case that if you have to sweat the price of tires, you’ve already bought the wrong vehicle.

Hope some of this is relevant.

My intuition is that run-flat and off-road would be a poor combo. But if you’re trailering the boat to a lakeside launch ramp or campground that ought not be an issue.

Hitting potholes can be more dramatic because there’s not as much give to the sidewalls. On low profile tires like mine potholes are already bad news run-flat or no. High profile tires like a pickup might suffer more ride degradation through a pothole or might even be more prone to forcing a blow-out. Too much force and not enough deformation to spread the impact across time and space. Smart pickup drivers avoid potholes; idjits shout “Hey y’all! Watch mah truck own this pothole!”. You’re not an idjit.

I went through the two big online tire retailers; neither break out truck tires by run-flat. I used a generic 2018 Silverado, 2wd, crew cab. I’m sure the truck tires exist, just a specific breakout is missing. A designator like RFT will be used in the tire description. Bridgestone Dueler H/L 400 RFT are a truck/SUV tire as an example. Note that most trucks have full size spares unlike cars which have “donuts” or a can of tire fix-it and a prayer.

Trailer run flat tires: They will require a pressure sensing device: “Because self-supporting tires are so good at masking the traditional loss-of-air symptoms that accompany a flat tire, they require a tire pressure monitoring system to alert the driver that they have lost air pressure. Without such a system, the driver may not notice underinflation and may inadvertently cause additional tire damage by failing to inflate or repair the tire at the first opportunity. Typically, self-supporting tires maintain vehicle mobility for 50 miles at around 50 mph.”

Also trailer tires are a different class from car/truck tires. Use of a car/truck tire in some states is an inspection fail. Trailer tires will have more plies for increased strength and load rating.

Thanks to everyone for their replies.

@LSLGuy: I especially appreciate the voice of experience, and am glad to know the tires will hold up, even at speed. My mission is of course a much lower velocity, but with less stability than your tuned sports car. So these tires may be a must for me. I sudden failure of a steer tire could be “interesting” when handling a long vehicle with a hinge (hitch) in the center. :dizzy_face:

@smithsb: Thanks for the head up about TMPS. I see the reason, since a trailer tire 30 feet behind me could undergo a lot of deflation and/or damage without it being obvious. I’ll look into aftermarket systems (I know they exist, but haven’t researched them much).

Next replacement cycle will be with run flats, based on what I’m learning. Will put them on the wife and kid’s car as well. pullinDaughter shredded a tire in Dallas last year, apparently due to debris also. I wonder if these will gain in popularity as road maintenance declines?

To offer a dissenting experience - I had run flats on my new AWD Toyota Sienna. That was the only set I ever had. As soon as they needed replacing, at the reco. of my tire dealer, I switched to regular tires and carry a can of the instant tire inflator / repair now.

To answer your original questions:

1. Is there a considerable difference in either ride, handling, or noise?
Yes - in my passenger vehicle, they were noticeably noisier. I didn’t notice a difference in handling or ride.

2. Do they actually work as advertised (ability to drive 20+ miles to repair at reasonable speeds)? I can’t say, never had a flat.

3. Do they last as long (miles) as typical tires? NO - this was the biggest issue I had. Mine lasted less than 25,000km (about 15,000 miles). I was stunned when my mechanic told me they need to be replaced after less than a year and a half of 75% city driving 25% (good) hwy driving. He said very short lifespan is the biggest issue with run flats.

4. Are there other issues I haven’t thought of?
The operating costs are way higher. For my van, they were more expensive to buy than comparable regular all-seasons, plus they last a fraction of the distance plus (I found) that when I switched to regular all-season (Michelins), my mileage jumped by about 10%.

In spite of my experience, I think your decision to try them is good, it’s not like you can’t switch back if / when you want. It sounds like you have specific driving conditions and situations that make it worthwhile to pay extra for the peace-of-mind insurance they’d offer you.

Heh, my experience was kind of extreme, due to the car. It was a MINI Cooper S with sport suspension. A teeny, light car, with really stiff suspension on really stiff tires is a bad combo if you’re driving down a rough road and need to go to the bathroom. I actually got rid of the run-flats because I was driving the car competitively, and the run-flats were at a distinct disadvantage in a sport where you can realistically lose by .001 seconds.

But, without the run-flats, the brutal boneshaking ride became at least a stiff, almost pleasant, tolerable ride. I drove it halfway across the country after changing to normal tires and sacrificing some of the limited storage space to a worn out race tire/wheel in the back for emergencies. Similar to LSLGuy’s BMW, there’s no place for a donut in the BMW produced Cooper S. My wife actually kind of enjoyed that trip, other than a long stretch of I-20 that was under construction. She hated even riding across town in it with the run-flats. It became something she could tolerate after I changed them.

Due to my experience, I’d advise switching one vehicle at a time and thinking about how it changed that one, if I were you. If it works on the smoothest riding one, then try it on the one with the next harshest ride. I enjoyed the convenience of driving home on a low tire without having to air it up before I plugged it at home once or twice before I ditched them from run-flats, but it wasn’t anywhere near worth the awful ride and generally worse handling those tires offered on that car. I used to drive a 3/4 ton truck, and I wanted all the handling and ride quality the M+S tires could offer. If you hit something bad enough and enough of the tread cap comes loose, it’s not going to save the fender well.

We do. Incandescent hatred actually.

In my experience, you’ll have a difficult time finding someone to plug/repair a run-flat. Most tire dealers won’t do it.

Thank you, that is something to think about. But the truck/trailer combo has a fairly high operating cost (per mile) anyway, but this is only for travel, not day to day commutes. I have a little Corolla as my daily runabout. I think (like you said) it will still be worth it.

Thanks for this advice. Unless they’ve changed policy, Discount Tire allows you to try out a set of tires and replace them with a similar set if you don’t like the ride. I’ve done this before with truck tires and there was no charge other than price difference. I’ll make sure they still do this (or find another chain that will). My plan is to start with the trailer tires, since the ride doesn’t matter, and they’re the ones that fail the most. I’ve lost several trailer tires over the years, but the recent one was the most “interesting”.

Thanks again to all for their advice.

Could well be. I get my tires, and my plugs, from the independent BMW shop I use for all my maintenance. So far they’ve not balked at all.

I suspect the difference is that a generic tire store sells/services run-flats as maybe 1 in 100 tires. For my guys run-flats are almost their entire tire business. So not so mysterious / unfamiliar to them.

Back to OP @pullin: ISTM you really need to have some sort of TPMS on the trailer.

Unwittingly dragging a heavily loaded dead tire a couple hundred miles to the next fuel / potty stop would be bad. Even if you have religion about manual tire pressure checks before you leave each stop, road hazards are everywhere, including the on-ramp 200 yards past wherever you just checked everything.

Agreed! …and already shopping. They seem to run around $150 on Amazon, so I’ll get a system even before I replace the tires next year. Might save my bacon no matter what type of tires are back there.

I’d agree with this. Run flats are a vanishingly small percentage of the market, like 3% or something. And that points out the other problem with run flats: if you damage one and need another, nobody but nobody stocks them (except perhaps your BMW-specific shop). If you’re out on the road in Sticksville, USA and suddenly have need of a replacement tire, you could be stuck there for days waiting for it to show up. I’d expect the OP’s pickup+trailer also hauls a full size spare, so not that big a deal perhaps in this case.

And in fact that’s almost exactly what happened with my tread failure on the Interstate. See this post from 2017 for the harrowing tale which was told in that thread for a totally unrelated reason.

I, too, has a Mini S. I’ll disagree it was bone shaking, though. I drove it across country. I liked it.

But out west here it can be 50 miles to the next town on the interstate, so I was still afraid of a total tire failure in the middle of nowhere. I’d rather have had a real spare.

I did have one shred the tread, with the steel belt flapping against the wheel well. Glad that was local.

Ok, but did yours have the R56 era sport suspension? It came with stiffer springs/shocks and a different roll bar. It was decidedly more stiff than the base S suspension, and most people I’ve spoken with agree that suspension option rode like a buckboard with run flats.

@pullin : Yeah, if you’re willing to return to the tire store, that will work. It’ll allow you to evaluate them on each of the vehicles, since even cars of the same model can be different depending on the options. I personally hate going there, and often buy tires that no one keeps in stock, so I shop hard before I order myself some tires.

I too have a BMW with runflats and they are a PITA. First, I’ve had 2 flat tires - they are EXPENSIVE to replace. One time, it failed in late September and there were no similar tires to be had (at least by the dealer) in Canada. So I switched to snow tires and they ordered the replacement, which showed up in November. When they called me, I said “OK, we’ll do the switch in March when I put summer tires back on and have the regular servicing done too.” Come march, they had forgotten this and shipped the tire back. ??? The other time, they repaired the tire while I waited a week or more for a replacement, but would not guarantee/recommend it for long road trips.

I assume there’s a hard sidewall inside the tire, so after pressure loss you are essentially riding on a pair of hard extra-large rims. What’s this “repair”? The dealer told me the tires likely are essentially garbage after running flat, however I kept them for emergency spares, given the delay to get replacements. Maybe when it’s time for new tires, I will get regular tires and for trips, order from; the difference in price between regular and run-flat should cover it. Most annoying is that for my model, front and back tires are different sizes.

When you hit a bad railroad crossing or pothole, there’s a noticeable “bang” like the shocks did nothing and hit bottom. but on regular roads, the only problem I had was the TPMS warning.

I do not have any experience with them, but a friend’s wife had them on a late model Toyota Sienna. He said that if one gets damaged beyond repair, then you need to replace all four - I guess you cannot have a new one with 3 others having some wear. Not sure if this is the case, tho.

BMW dealer never mentioned any such thing. I can see that you want the tread on your tires to be somewhat even, so if it’s close to out of tread, probably a good time to replace the set.

Mine was the opposite - I replaced two (summer) tires in less than 2 years, so I had a balanced newer pair on the back wheels and had to replace the fronts when the tread got too bare.

As opposed to purchasing “run flats” I would propose regular checking of tire inflation, tread wear, rotation and finally replacement. In the 40 something years of driving, I’ve never had a “blow-out”. Sure, I’ve had a tire lose pressure because I’ve picked up a nail or screw, and had to have it repaired, but never a full on blow out of the tire.