This happens too often to be coincidental

[The Gritz Carlton]

Watch Chase Elliott win the NASCAR Cup Series Championship this weekend. One of the tactics they use to slow another car down "while passing" is the "side draft". It disturbs the even flow of air around the other car and creates an actual vacuum between both cars, allowing the passing car to boost ahead. This is the same effect you are feeling when being passed. Just move over to the right edge of your lane when being passed and the effect will either go away or become greatly reduced.

[NMRVer]

My .02.
Antisway bars and a stearing stabilizer are the best way to stop getting blown all over.
For my challenger front and rear made a very big difference and it also stopped us from getting that we're tipping over feeling going around corners.

If you have the money, new aftermarket air ride systems are great.

Each brand has pros and cons. We choose Road master.

[hikerjohn7]

Originally Posted by RACarvalho

And why are you trying to pass 18 wheelers?
Simple solution is drive 65mph or less and then they have to be concerned with that!!!

Just teasing you....

ACE just told you above.

You may be teasing but it's the best suggestion so far put forth in this blog thread. Getting behind semis, though not too close mind you, is the safest strategy. It takes a little longer to get there but your chance of making your destination without wrecking your RV is drastically reduced. That's especially true if you blow a steering tire which can make you lose control at high speeds.

[roy stone]

Could be wind, suction, or some other reason, do you give ample indication by signaling your intent prior to passing? Sometimes our
driving habits are so entrenched that they could be at fault also.

[TRMott]

Originally Posted by 16ACE27

More likely, at their phones. We see it all the time when they can't seem to stay in their own lane.

You're not kidding! We see the glow on their faces, as they are looking down, from their phones or tablets! We have even seen what looks like a tablet/laptop mounted and they're watching it! I don't know how they get away with that! If I can see it, why can't Hwy Patrol see it??

[TRMott]

Originally Posted by Jusplainwacky

I don't get this...on a long trip and passing many 18-wheelers along the way I found many of them start to wander over towards me as I'm passing them...and I'm not talking just slightly. Sometimes I thought our mirrors would hit. And there were times that my SO would be saying "WATCH OUT"!!
It happens too often to be coincidental and many times I find myself trying to leave plenty of room between me and them when passing.

What puzzles me is why are they drifting over??

We have also noticed how they swerve near, but during the summer we were running with windows open for air and noticed it less, so suction, and not paying attention to the road, would also be my guess. (and now I am reading peeing?!)

As for stabilizers, we took ours to Safe-T-Plus and had one installed on the rear. WORLD of difference! It can be installed on your own but we took ours to them and they do it without labor charges at their place.

[TRMott]

Originally Posted by MJC62

Have a friend who is a truck driver and he says when truckers are wandering all over the highway back and forth over the lines, they are pissing in a cup.

NOOOO! Thanks for that image! That being said...you, and SIMIDM, are probably correct!

[Bob Nodine]

Modern semi trucks have powerful engines with automatic transmissions and it takes a big hill to slow them below 70 MPH. If you are passing semi trucks you are driving to fast for a motorhome. I find it best to select a speed where most of the traffic is passing me so I can leave the cruise control on and don't have to keep hitting the brakes. Usually 63 to 64 MPH works best. Sit back and relax, enjoy the scenery, and lower your frustration.

[Jimbo56]

Originally Posted by The Gritz Carlton

Watch Chase Elliott win the NASCAR Cup Series Championship this weekend. One of the tactics they use to slow another car down "while passing" is the "side draft". It disturbs the even flow of air around the other car and creates an actual vacuum between both cars, allowing the passing car to boost ahead. This is the same effect you are feeling when being passed. Just move over to the right edge of your lane when being passed and the effect will either go away or become greatly reduced.

The Phoenix race? Joey Lugano won!

[Jimbo56]

Originally Posted by TRMott

You're not kidding! We see the glow on their faces, as they are looking down, from their phones or tablets! We have even seen what looks like a tablet/laptop mounted and they're watching it! I don't know how they get away with that! If I can see it, why can't Hwy Patrol see it??

Cuz HP are watching theirs!

[RACarvalho]

Originally Posted by Bob Nodine

Modern semi trucks have powerful engines with automatic transmissions and it takes a big hill to slow them below 70 MPH. If you are passing semi trucks you are driving to fast for a motorhome. I find it best to select a speed where most of the traffic is passing me so I can leave the cruise control on and don't have to keep hitting the brakes. Usually 63 to 64 MPH works best. Sit back and relax, enjoy the scenery, and lower your frustration.

Exactly.
To add to that, because you are not stressing that much, you can increase the distance between rest stops and by the end your average speed is the same or better than someone that is driving at a higher speeds but stopping frequently.

I remember this trip where a guy on a Corvette passed me 4 or 5 times but I never passed him!

Trick is to make driving the MH the least stressful possible so you can go farther... and as a bonus you are safer...

[Metalman]

Originally Posted by Bob Nodine

Modern semi trucks have powerful engines with automatic transmissions and it takes a big hill to slow them below 70 MPH. If you are passing semi trucks you are driving to fast for a motorhome. I find it best to select a speed where most of the traffic is passing me so I can leave the cruise control on and don't have to keep hitting the brakes. Usually 63 to 64 MPH works best. Sit back and relax, enjoy the scenery, and lower your frustration.

And increase your MPG.

[hikerjohn7]

Originally Posted by Bob Nodine

Modern semi trucks have powerful engines with automatic transmissions and it takes a big hill to slow them below 70 MPH. If you are passing semi trucks you are driving to fast for a motorhome. I find it best to select a speed where most of the traffic is passing me so I can leave the cruise control on and don't have to keep hitting the brakes. Usually 63 to 64 MPH works best. Sit back and relax, enjoy the scenery, and lower your frustration.

Your description as to how you like to drive your RV gets a thumbs up with me. There is a valid reason why professional fleet trucking companies required their trucks to drive at 65 mph. Not only does it save lives, it reduces risks of loss of vehicles and resulting law suits. And when you are driving an RV, especially with a toad on the back, the risks are similar and are much greater than a car. Driving an RV at 70 is risky because it takes much longer to stop than a car and it is much more prone to roll over. And my biggest fear is blowing a front tire. Your chances of losing control like we see in so many videos where blowouts result in RVs going off the road.

And another thing many RV drives don't realize is that you don't have as much protection in a Class A RV as you do in a car. You don't have all that engine metal between you and the front of the vehicle. If you roll, all over, all you have is a big glass window between you and anything you might impact.

So, I agree. Stay under 65 to be safe and keep lots of distance from other vehicles. You can enjoy the trip so much more since you seldom have to even get out of the right lane.

[Dan-sr@perra-us.net]

Originally Posted by hikerjohn7

And another thing many RV drives don't realize is that you don't have as much protection in a Class A RV as you do in a car. You don't have all that engine metal between you and the front of the vehicle. If you roll, all over, all you have is a big glass window between you and anything you might impact.

Or a truck for that matter.

[hikerjohn7]

Originally Posted by Jusplainwacky

I was wondering if that was the case...but I also questioned if it might be them looking in their side mirrors and not where they are going.

I plan to review threads about stabilizers, cause I was in high wind areas, and I was getting blown all over. I ended up buying one but haven't put it on.
But what puzzles me, is how does a stabilizer keep the rig from being blown around or when passing these rigs? Seems to me that the wind is going to push the rig regardless if you have stabilizer on.

I am a retired engineer and I have always been intrigued by why an RV, when it gets hit by a side wind, tends to steer to the side. Unlike cars, it's steering has to be continuously corrected in windy weather and when trucks pass. A large RV is like a big sail. So I can see how the wind gusts place large instantaneous side loads on the RV causing it to tilt. But you would not think that that would actually change the RV's direction. But it definitely does.

The only explanation I can come up with is that it's because the rear tires, being dual tires, are stiffer to side loads than the front tires. So, the front tires deflect sideways more than the rear tires when the wind pushes on the side of the RV. That causes the angle of the RV's frame to the road to change slightly. And the slight angular change could be what makes the RV steer sideways.

In the case of passing semi trucks, I think the semi creates a vacuum and actually sucks the RV toward it which has the same effect as wind side load. I have noticed that as the truck gets right up to the RV, my rig tends to lurch towards the truck. It's a pain but I have kind-of conditioned myself to be ready for it.

Some claim that stabilizers help but I am not sure why unless the steering mechanism is somehow also deflected by the wind side load and the stabilizers add stiffness to that system. I have a Jayco with J-Ride which is supposed to be a stabilizing system. I think it helps somewhat but I my class A still steers off course during wind gusts and when semi trucks pass.

One thing I have learned there is that when you pass open fields with no trees or open water, expect higher wind gusts and be on the alert with both hands on the will. There is definitely a skill factor involved in driving tons of equipment at highway speeds. My guess is that professional large truck drivers experience very similar challenges.

[Metalman]

I am not sure if this holds true with all motor homes, but our first motor home was a Class C and it was much heavier in the rear than in the front. I don't remember any serious problems with stability in cross winds or when being passed by a semi, but I sure learned about braking early, when I had to apply the brakes forcibly and the front tires lost traction.

[16ACE27]

Originally Posted by hikerjohn7

I am a retired engineer and I have always been intrigued by why an RV, when it gets hit by a side wind, tends to steer to the side. Unlike cars, it's steering has to be continuously corrected in windy weather and when trucks pass. A large RV is like a big sail. So I can see how the wind gusts place large instantaneous side loads on the RV causing it to tilt. But you would not think that that would actually change the RV's direction. But it definitely does.

The only explanation I can come up with is that it's because the rear tires, being dual tires, are stiffer to side loads than the front tires. So, the front tires deflect sideways more than the rear tires when the wind pushes on the side of the RV. That causes the angle of the RV's frame to the road to change slightly. And the slight angular change could be what makes the RV steer sideways.

In the case of passing semi trucks, I think the semi creates a vacuum and actually sucks the RV toward it which has the same effect as wind side load. I have noticed that as the truck gets right up to the RV, my rig tends to lurch towards the truck. It's a pain but I have kind-of conditioned myself to be ready for it.

Some claim that stabilizers help but I am not sure why unless the steering mechanism is somehow also deflected by the wind side load and the stabilizers add stiffness to that system. I have a Jayco with J-Ride which is supposed to be a stabilizing system. I think it helps somewhat but I my class A still steers off course during wind gusts and when semi trucks pass.

One thing I have learned there is that when you pass open fields with no trees or open water, expect higher wind gusts and be on the alert with both hands on the will. There is definitely a skill factor involved in driving tons of equipment at highway speeds. My guess is that professional large truck drivers experience very similar challenges.

It is simply caused by the bow wave of air pressure and rear suction acting on the rear, and then the front of the MH side areas.

Speed difference and separation increase/decrease the effect. Happens to towable RVs as well.

[EA37TS]

Originally Posted by hikerjohn7

I am a retired engineer and I have always been intrigued by why an RV, when it gets hit by a side wind, tends to steer to the side. Unlike cars, it's steering has to be continuously corrected in windy weather and when trucks pass. A large RV is like a big sail. So I can see how the wind gusts place large instantaneous side loads on the RV causing it to tilt. But you would not think that that would actually change the RV's direction. But it definitely does.

The only explanation I can come up with is that it's because the rear tires, being dual tires, are stiffer to side loads than the front tires. So, the front tires deflect sideways more than the rear tires when the wind pushes on the side of the RV. That causes the angle of the RV's frame to the road to change slightly. And the slight angular change could be what makes the RV steer sideways.

In the case of passing semi trucks, I think the semi creates a vacuum and actually sucks the RV toward it which has the same effect as wind side load. I have noticed that as the truck gets right up to the RV, my rig tends to lurch towards the truck. It's a pain but I have kind-of conditioned myself to be ready for it.

Some claim that stabilizers help but I am not sure why unless the steering mechanism is somehow also deflected by the wind side load and the stabilizers add stiffness to that system. I have a Jayco with J-Ride which is supposed to be a stabilizing system. I think it helps somewhat but I my class A still steers off course during wind gusts and when semi trucks pass.

One thing I have learned there is that when you pass open fields with no trees or open water, expect higher wind gusts and be on the alert with both hands on the will. There is definitely a skill factor involved in driving tons of equipment at highway speeds. My guess is that professional large truck drivers experience very similar challenges.

Cars and SUVs are also subject to crosswinds. I first learned this in the 80’s driving through Kansas during March in a Grand Prix. 25 mph cross winds weren’t noticeable until you went under an overpass then the vehicle would lurch because you didn’t realize you were holding the wheel in a manner to compensate for the wind.

Only difference is the car or SUV is smaller and easier to drive that an RV with more sidewall surface area acting as a sail.

There have a few times when our Grand Cherokee has been blown around by trucks on the highway. Here it could be the surface area of a truck momentarily blocking a crosswind.

Bottom line, why it happens, I don’t know and I don’t care and I, repeat I, was concerned about how the RV handled I wouldn’t own it and I would stick to things that were within my area of driving skill and comfort level.

[Dan-sr@perra-us.net]

Originally Posted by Jusplainwacky

I don't get this...on a long trip and passing many 18-wheelers along the way I found many of them start to wander over towards me as I'm passing them...and I'm not talking just slightly. Sometimes I thought our mirrors would hit. And there were times that my SO would be saying "WATCH OUT"!!
It happens too often to be coincidental and many times I find myself trying to leave plenty of room between me and them when passing.

What puzzles me is why are they drifting over??

Maybe just trying to get a good look at your "Seat Covers".

[Trophy1200]

Google Venturi effect and all will be revealed.

Happy New Year.