2009 BMW 750i: Tale of Two Flat Tires
October 30, 2009
Getting two flat tires in a single trip takes some luck, and getting two flat tires within 25 minutes takes some skill. But when the tire we're discussing is the same tire...well, I'm not sure what that takes. Maybe it's just a matter of acknowledging a greater power really wanted that tire to be flat!
Or at least as flat as our long-term BMW 750i's run-flat tires can be.
It all started with a random lane change on the 101 freeway. Halfway through it I spotted road debris but I had no real option to avoid it without massive steering input at roughly 65 mph. It looked like nothing more than a blue party streamer, so I didn't think it deserved drastic or dangerous action on my part.
"Hmm, that seemed loud for a paper streamer..."
About 10 minutes later I heard a "DING" and the LCD screen lit up with the first message above. I figured it was more than just a paper streamer I had hit with my right front tire. But at that point I was on Malibu Canyon Road with no where to stop, plus I knew the BMW 750i had run-flats so I figured I'd get to PCH and stop at a gas station.
Once parked it didn't take long to spot the problem. In fact, a good chunk of the blue streamer remained with the tire, conveniently marking the nail's location. And once again, between the run-flat sidewall and the lack of any obvious signs of air loss (no squished sidewall or scary sounds, vibrations or pulls from behind the wheel) it seemed a no-brainer to continue on and stop at Stokes Tire Pros in Santa Monica for a simple patch. I even called ahead and told them I would be there in 15 minutes.
Probably about 45 seconds after hanging up, while heading south on PCH behind a large truck (I was staying in the slow lane and keeping it under 45, just to be safe) I spotted a massive pothole just as it slipped out from under the truck before disappearing under the BMW. It was on the right side. Lined up perfectly with...
The right front tire, already confirmed to be carrying a nail and rolling on low tire pressure according to the 750i's gauge cluster, slammed into said pothole.
This was immediately followed by a definite sound, vibration and pull coming from the right side of the car. I uttered several inappropriate words and pulled into another gas station to see if there was any visible change in the tire's condition. The now-drooping sidewall was easy to spot, but a closer examination revealed the new issue with the tire.
I've rarely seen a tear this large in a sidewall, and I've never seen one like this in a run-flat tire. I'll probably never know if the pothole would have done this to any tire, or if it was a combination of the existing low tire pressure and the impact that ripped this hole in the 245/45R19 Goodyear Excellence.
I still made it to Stokes (about 10 miles away), but I was now using the flashers and staying under 30 mph. They had to special order the tire, but they had it installed by mid-afternoon. They also gave the car a four-wheel alignment, something I suggested given the severe impact and clear evidence of force traveling through the car's right-side front suspension.
Final bill: $473.62.
I now have a new appreciation for the capabilities of both run-flat tires and potholes.
Karl Brauer, Edmunds.com Editor in Chief @ 19,730 miles