Keep in mind that while energy is 1/16 of 80 mph, speed is only 1/4. That means reaction time still matters, and you must be fully attentive. As a limper, you have one job.

Why not just tow or use the spare tire, if a blowout is so certain? Tell you a secret, a blowout is rather unlikely at 20 mph. But we're gonna plan for the worst and hope for the best.

Keep in mind that while energy is 1/16 of 80 mph, speed is only 1/4. That means reaction time still matters - it will be 1/4 not 1/16 - so you must be fully attentive. As a limper, you have one job - to react promptly to the expected problem.

Why not just tow or use the spare tire, if a blowout is so certain? Tell you a secret, a blowout is rather unlikely at 20 mph. But we're gonna plan for the worst and hope for the best.

Depends what you mean by "driving".

• The car can certainly be hostled around your driveway.
• You can venture around local streets in your neighborhood if you keep it below 20 mph or so. The general concept is don't drive it hard/"normal".
• You can zigzag through side streets to get from your house to a wheel shop, Pick-n-Pull, what have you, again keeping it down to 20 mph.

Venturing out onto arterial roads should be kept to an absolute minimum, because you can't move fast enough to be safe -- a car going a dramatically different speed from everyone else creates a significant hazard to other drivers.

The freeway is out of the question.

What's the deal with going so slow?

The amount of kinetic energy decides how much mangulation will happen in a crash, and how hard the car will be to control in a tire blowout.  Moving the car would be a lot safer if we could keep that small.

Well, as it happens, here is the formula for kinetic energy: V is velocity (speed), M is mass (the weight of the car) and E = kinetic energy.

 E = M x V x V

See, we multiply by V twice. If M stays the same (which it will) but we triple V, then E goes up by nine times!

So by driving 1/3 normal speed (20 instead of 60 mph) we reduce kinetic energy by a factor of nine. That means in the fairly high probability of a tire blowout, you'll be able to still control the car.

The wheel is done, so you're better off just buying a spare.

You can buy matching OEM wheels online from a variety of web sites, and also through interchange amongst full-service scrap yards.

The wheel is made of aluminum and steel, and recycles nicely. Let the tire shop do it. If the tire is undamaged just have a tire shop transfer it to the new wheel.

Limping: Stay under 20 mph at all times. Expect a blowout!

• You can venture around local streets in your neighborhood if you keep it below 20 mph or so. The general concept is don't drive it hard/"normal".
• You can zigzag through side streets to get from your house to a wheel shop, Pick-n-Pull, what have you, again keeping it down to 20 mph.

Venturing out onto arterial roads should be kept to an absolute minimum, because you can't move fast enough to be safe -- a car going a dramatically different speed from everyone else creates a significant hazard to other drivers. If you have heavy commute hours, exploit them: for instance if I had to cross the Golden Gate Bridge I would do it in the thick of commute hour, where you'd be lucky to go 20 mph.

The freeway is out of the question.

What's the deal with going so slow? Physics.

We're assuming there will be a blowout or wheel breakage, and moving so slow it's safe.

The amount of kinetic energy decides how much mangulation will happen in a crash, how much forces will act on the car in a tire blowout, how much dynamic force acts on the wheel when you hit a bump, etc. It's impractical to move the car unless we can keep these forces VERY small.

Here is the formula for kinetic energy.

E = M V ²

Energy = Mass (car weight) x Velocity (speed) squared.

The squaring of velocity is what makes this possible. If you go 1/4 the speed, you have 1/16 the kinetic energy. Cars are designed for blowouts to be manageable by a competent driver at 80 mph. At 1/16 of that, they're so easy I have confidence anyone can do it.

At the low speed, things happen at proportionately lower speed (1/4 of 80 mph). But the main win is the massively lower kinetic energy, which does some things for us.

• It lets the brakes stop in 1/16 the distance- less than the car's length!
• A blowout may make the car swerve out of the lane (though I've blown out tires at 80 mph and it didn't do much of that). But where does the energy come from to swerve? The kinetic energy of the car - which we reduced to nothin'. So the swerve won't be hard or fast; you can easily counteract it with the steering wheel.
• The car can't flip over; there's not enough kinetic energy to do that.

Keep in mind that while energy is 1/16 of 80 mph, speed is only 1/4. That means reaction time still matters, and you must be fully attentive. As a limper, you have one job.

Why not just tow or use the spare tire, if a blowout is so certain? Tell you a secret, a blowout is rather unlikely at 20 mph. But we're gonna plan for the worst and hope for the best.