Tire Has Sudden Loss Of AIR!

[4x4van]

I'm not even going to get into the wisdom of running 70+mph in a 20K-80K vehicle, but I agree with Cat320, and to some extent Cloud Dancer. The graphics in that video are highly exaggerated to overstate the side forces and understate the forward forces. And the exact same forces that you supposedly eliminate by stomping on that throttle, come back as soon as you DO let off the throttle. You've accomplished nothing other than traveling another 280+ feet (the length of a football field) before you even begin to slow down.

In my 28+ years of driving RVs, I've had several tire blowouts, 2 of them on the right front. Once at speed (I run at 65mph), and once while beginning down a freeway offramp (still running at least 55-60mph). In neither case did I stomp on the accelerator. Rather, I let off the throttle, maintained steering control, and smoothly applied the brakes to slow the rig to a stop. At no point was the "pull" significant enough to cause any fear or concern (the only thing that is "scary" about a blowout is the loud "BANG") even when going downhill, nor did it significantly try to pull me into another lane. For those of you who say that stomping on the throttle for a few seconds will not result in any increased speed, try this: Next time you are going down the highway and you are following behind someone, stomp on the accelerator and hold it there for 2-3 seconds. Then come back and tell us how your DW sitting in the passenger seat reacts, and how long it takes for your black eye to heal! You WILL have to get on the brakes (or at least let off the throttle completely) to keep from running into that vehicle in front of you. And even if you don't accelerate very much, you've still just covered another football field without making any progress whatsoever to get your disabled rig stopped.

The most important thing in any blowout is to not panic and stomp on the brakes. But every couple of months, someone posts that same video. So now, on with the show

[bamaguy911]

Originally Posted by 4x4van

And the exact same forces that you supposedly eliminate by stomping on that throttle, come back as soon as you DO let off the throttle. You've accomplished nothing other than traveling another 280+ feet (the length of a football field) before you even begin to slow down.

Totally agree with the first sentence. One only "stomps" the accelerator for a second or two. At 60mph, you will travel 88 to 176 feet while you are trying to maintain control, not the 280 feet.

..........try this: Next time you are going down the highway and you are following behind someone, stomp on the accelerator and hold it there for 2-3 seconds. Then come back and tell us how your DW sitting in the passenger seat reacts, and how long it takes for your black eye to heal! You WILL have to get on the brakes (or at least let off the throttle completely) to keep from running into that vehicle in front of you.


IMO, this is not an issue in a motorhome or a big truck, unless you have a monster powerplant powering it. If I tried this in my Caddy SRX, the actions from my DW would be similar to the one you mentioned.
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The most important thing in any blowout is to not panic and stomp on the brakes.

Very true!

I wish safe travels and NO sudden loss of air to all!

[4x4van]

Originally Posted by bamaguy911

One only "stomps" the accelerator for a second or two. At 60mph, you will travel 88 to 176 feet while you are trying to maintain control, not the 280 feet.

Most people that tout the value of that video say 2-3 seconds. And I am using a speed of 65mph as a basis since lower than that should be relatively easy to control anyway. The videos I keep seeing of RVs losing control after a blowout are almost universally going even faster than that. At just 65mph, you are traveling 95 feet per second, that's 190' in 2 seconds, 286 feet in 3 seconds. Oh, and the video? No fewer than 5 times in that video, the driver floors it for at least 6 seconds before releasing the gas pedal. 6+ seconds! That's nearly 600' (at 65mph)! He even says to floor it till you regain stability!

Originally Posted by bamaguy911

IMO, this is not an issue in a motorhome or a big truck, unless you have a monster powerplant powering it. If I tried this in my Caddy SRX, the actions from my DW would be similar to the one you mentioned.

While flooring it for 2-3 secconds will not result in a dramatic increase in speed, it WILL increase your speed at least a bit. And 6+ seconds? 2 black eyes from the DW!

[Cloud Dancer]

Without exemption, all the front tire blowouts which resulted in loss of contol, in large motorhomes, that I have looked at over and over, have convinced me that the drivers where substandard, OR suffered some kind of incapacitation.
Yes, IMO if it happens to a johnny-come-lately, no-experience driver,...it's almost to be expected that the first thing they do is stomp on the brake,....which IMO is a ticket to the guard rail or the ditch.
Also, why would you want to be in a hurry to touch the accelerator if you're on cruise control. If you do that, it tells me you do NOT understand how the propulsion system in your motorhome works, nor what causes the asymmetric thrust AFTER the front tire blows.
The power steering, AND the asymmetric thrust are the two most important forces which can help you retain control, in event of a front tire failure (if you know how to use them).

[Lt46]

I'm here to say the advice offered by Michelin worked for me. At 65 mph in the left lane, my LF blew out. I experienced a strong pull to the left, not from the steering wheel turning but due to the front-end drop and friction from the tire shredding with each revolution. The LF had crossed the white paint lane marker with the remaining 10" of asphalt left between me and the grassy median. I stepped on the gas and felt the persistent leftward tug release with minimal rightward steering wheel correction. I couldn't tell you if it was gas application or the actual complete shredding of the tire, leaving me on riding on the rim that made me feel back in control of the rig. Whatever it was, I was then able to get off the the breakdown lane to safety. The application of power sure seemed to help in this scenario and no, I didn't have a stop watch to time how long I gassed it or a tape measure for how far I traveled. My belief is it was for seconds though.

[Cloud Dancer]

Originally Posted by Lt46

I'm here to say the advice offered by Michelin worked for me. At 65 mph in the left lane, my LF blew out. I experienced a strong pull to the left, not from the steering wheel turning but due to the front-end drop and friction from the tire shredding with each revolution. The LF had crossed the white paint lane marker with the remaining 10" of asphalt left between me and the grassy median. I stepped on the gas and felt the persistent leftward tug release with minimal rightward steering wheel correction. I couldn't tell you if it was gas application or the actual complete shredding of the tire, leaving me on riding on the rim that made me feel back in control of the rig. Whatever it was, I was then able to get off the the breakdown lane to safety. The application of power sure seemed to help in this scenario and no, I didn't have a stop watch to time how long I gassed it or a tape measure for how far I traveled. My belief is it was for seconds though.

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Obviously, not all of us give hoot about the origin of the helpful force which comes into play when you "step on the gas". But, I will try to explain it anyway:
First, it has to originate from the power output of the engine, which said power is transferred to the drive axle by way of the differential gears, the axles shafts, and to the 2 pairs of drive tires (2 per side). Normally, the resulting propulsion is fairly equal, side to side (due to the fairly equal distribution of vehicle weight). But, when suddenly a front tire becomes five(5) inches shorter, the distribution of weight is no longer normal. There is significant weight transferred to the healthy front tire PLUS to the dually set of REAR tires which are on the SAME side of the failed FRONT tire. Due to the design of the differential rear axle gears, and how they work, these 2 drive tires, which are now supporting more weight, will develop more THRUST than the drive tires on the opposite side. This is called asymmetrical thrust. This is the thrust that will now try to veer the front of the vehicle to opposite side of the failed front tire. This is the reason you should NOT reduce your cruising power. Now, if you are on cruise control IMO it's more intuitive to leave it in cruise control than it is to "step on the gas". Obviously, the author of the Michelin Tire video believes it's added insurance to "step on the gas". Me, I've found out that on my big diesel pusher, it's sufficient to just leave the power level where it is. Keep it mind, that you suddenly have an added advantage anyway. The added weight on the healthy front tire now HAS MORE traction also. This means it is now more effective when you turn the steering wheel to the opposite side of the "pull-to-the -ditch".
It's been proved many times, if the driver remains cool and immediately executes the two(2) first CORRECT steps, and also does not touch the brake,...a blown front tire should be a "non-event".

[V3600]

There's another thread going talking about this subject. I posted the following from the current CDL training manual:

Tire Failure

Hold the steering wheel firmly — If a front tire fails, it can twist the steering wheel out of your hands. The only way to prevent this is to keep a firm grip on the steering wheel with both hands at all times.

Stay off the brake — It is natural to want to brake in an emergency. However, braking when a tire has failed could cause loss of control. Unless you are about to run into something, stay off the brake until the vehicle has slowed down. Then brake very gently, pull off the road and stop.

Check the tires — After you have come to a stop, get out and check all the tires. Do this even if the vehicle seems to be handling all right.