Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations - Page 3





Page 3 of 3 FirstFirst 1 2 3
Results 41 to 54 of 54
  1. #41
    Join Date
    Nov 2010
    Location
    Somerset West
    Age
    61
    Posts
    2,124
    Thanked: 794

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Thank you for confirming your experience as well. I don't intend to disagree, just adding my additional chirps on what you've written between your text in blue.

    Quote Originally Posted by Henris View Post
    I haven't read through all of this, but this is my take.


    1. Measurements of the trailer. The old golden triangle is of utmost importance. The wheels need to face 100% forward and the towball must be dead center. When you do these measurements, forget about the vehicle(trailer) measurements. The wheels and the coupler are the focus.

      While these geometrics are excellent design/build discipline, they're not going to stop a trailer from swaying. (The towball will always be dead centre, when this is off centre, the back of the trailer crabs and your wheel toes go in and out either end - correct that and you're spot on again.)
    2. Weight on the towball is a huge factor. There is a percentage in the theory somewhere, but I am not sure what that is. I just make sure that the weight on the towball is substantial.

      The rule is 10% of the trailer weight with a minimum of 30 kgs and a maximum of 100 kgs. In Australia and the US you can continue increasing tow-ball weights, but not for the EU spec which SA has adopted almost ad verbatim. So with this legal limitation in mind, it becomes more difficult to resolve an unstable tow using the tow-ball weight method.
    3. The load must be stable. Totally stable. When you have things in the caravan or trailer, they must not move. So either secure with a net, or just tie them down. On corrugations the load tends to "walk". Or when you get into that sway, the load will add to the sway.

      100%

    4. When you do pick up a sway, calm down and think. Watch the trailer. There are plenty warnings on the trailer that starts to sway. So don't try and fight that sway. Anticipate and then respond. You could watch the load and when you see the load line up, jump on the brakes. The idea is to get the trailer brakes to engage and pull straight. You can also accelerate to pull the load straight. NEVER fight that sway.

      100% - it takes a bit of courage to hit the brakes at the right time, but it's better than loosing control of the entire rig.
    5. When you tow, you never steer of drive the car. You guide it. Be gentle. Don't force anything. I will, every time I load a weight, test the response of the trailer. Try and induce the trailer into a sway and the adjust the load as needs be.

      100% - test the rig you're towing so you know it's point of instability while you still have some safety and control of the environment.
    6. Tire pressures are important. So run as hard as you are permitted by circumstances. When I have loaded a rigged car, I run at about 3.5bar. Keeps the load stable and the tyres cool. When I am empty, on tar I run at about 2.5-3 bar. Gravel I will go down to about 2bat empty and about 3 bar loaded.

      100% - I forgot to add this to my list of instability causes. Tks for picking up on this.
    Henri, you're towing massive loads that constantly change and your experience in this regard surely exceeds mine. Respect. If I may add another point on wheel alignment. Numerous trailers take a big knock every now and then. This generally results in a slight tow out with positive camber. The positive camber is not an issue, but toe out also adds to the trailer wanting to swim a bit, notably as one side takes more load (traction) than the other, the trailer will veer outwards. The rule is to be at zero or up to 0.5 degrees toe in. Supposedly the wear on the tyre is also lessened with a slight toe in - but I cannot confirm this.

  2. #42
    Join Date
    Dec 2014
    Location
    Cape Town
    Age
    54
    Posts
    3,276
    Thanked: 2175

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by Heinz Modricky View Post
    Thank you for confirming your experience as well. I don't intend to disagree, just adding my additional chirps on what you've written between your text in blue.



    Henri, you're towing massive loads that constantly change and your experience in this regard surely exceeds mine. Respect. If I may add another point on wheel alignment. Numerous trailers take a big knock every now and then. This generally results in a slight tow out with positive camber. The positive camber is not an issue, but toe out also adds to the trailer wanting to swim a bit, notably as one side takes more load (traction) than the other, the trailer will veer outwards. The rule is to be at zero or up to 0.5 degrees toe in. Supposedly the wear on the tyre is also lessened with a slight toe in - but I cannot confirm this.
    When you do pick up a sway, calm down and think. Watch the trailer. There are plenty warnings on the trailer that starts to sway. So don't try and fight that sway. Anticipate and then respond. You could watch the load and when you see the load line up, jump on the brakes. The idea is to get the trailer brakes to engage and pull straight. You can also accelerate to pull the load straight. NEVER fight that sway.

    100% - it takes a bit of courage to hit the brakes at the right time, but it's better than loosing control of the entire rig.
    That is what saved my bacon in my incident.
    I was with a friend who was an old time caravan user and he said to accelerate through it, which worked fine until we needed to slow down again, then it started all over again, except at higher speed....
    I was on a quiet road with a slight downhill, so I aimed the El Camino I was towing with down the middle of the road and waited until the trailer's leading side passed from view in the mirror and braked hard until the trailing corner reappeared on the other side and let off the brakes, repeat once it had started back the other way until we coasted to a stop.

    There was an articulated rig at the bottom of the slope when we crested to go down and he pulled up next to us and he said he had never seen so bad a sway that still stayed upright.
    Cheers,
    John Kilfoil

    Rover P6
    Land Rover Discovery II Td5 Manual
    Range Rover P38 HSE
    Moto Guzzi LeMans
    Aprilia Tuono V2

  3. #43
    Join Date
    Nov 2010
    Location
    Somerset West
    Age
    61
    Posts
    2,124
    Thanked: 794

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by JohnnoK View Post
    I was with a friend who was an old time caravan user and he said to accelerate through it, which worked fine until we needed to slow down again, then it started all over again, except at higher speed....
    Yep, that only works if you have an steepish uphill ahead of you that you can reach in time to slow down on again.

    Best of all, that's now three of us that confirm that braking as the sway comes in line with the car is the best action to take. Took me some time to work this out.

  4. #44
    Join Date
    Apr 2014
    Location
    Roodepoort
    Age
    64
    Posts
    1,229
    Thanked: 3881

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    For now I will keep the speed down. We are not in a hurry. XPlorer is too heavy to take a risk.

    Quote Originally Posted by janseekat View Post
    Jouko
    I have an xplorer fitted with a oldish Trapezium . My caravan show no sway when passing a truck. Also tows excellent at 110 +. Also towed gravel (C28) and the trapezium performed good.But for gravel etc the nylon or whatever material bushes wont last long. There are 4 of them on the trapezium. The locking pin mentioned is only for reversing. Without it it is mission as the sway arm will bend and the movement of the Trap. requires more steering movement.
    Jouko
    ----------
    2003 Grand Cherokee 4.7l
    2012 Smart
    Never drive a normal car 8)

  5. #45
    Join Date
    Dec 2014
    Location
    Cape Town
    Age
    54
    Posts
    3,276
    Thanked: 2175

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by Heinz Modricky View Post
    Yep, that only works if you have an steepish uphill ahead of you that you can reach in time to slow down on again.

    Best of all, that's now three of us that confirm that braking as the sway comes in line with the car is the best action to take. Took me some time to work this out.
    Wasn't an uphill, rather the flat bit before the down slope.
    I am testament that Adrenaline is brown.....

    Mine was a combination of poor loading because the car I loaded was nose into the garage and I had to back down a driveway to get to it, so the engine was at the rear of the trailer and bad luck because we were doing fine up to the point where the one tyre half threw it's retread off and developed self-steering...
    Cheers,
    John Kilfoil

    Rover P6
    Land Rover Discovery II Td5 Manual
    Range Rover P38 HSE
    Moto Guzzi LeMans
    Aprilia Tuono V2

  6. #46
    Join Date
    Apr 2007
    Location
    Nigel
    Age
    59
    Posts
    16,139
    Thanked: 2402

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    There is another way, that I have used.

    As soon as you feel the sway, then yank the steering left to right. But not at the same time as the trailer. The idea is to break the oscillation. So if the osculation is every 2 sec, then yank your steering every second.

    But, I recommend you play with this and make sure you can manage it.
    Last edited by Henris; 2020/10/29 at 07:39 AM.
    LC 78 Troopie 1HD-FTE
    Uniglide
    +27 zero eight 2 four 95 9252

  7. #47
    Join Date
    Oct 2011
    Location
    Midrand
    Age
    49
    Posts
    3,056
    Thanked: 1076

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    I have only once ever had a serious trailer sway and that was towing a Merc230e back from Ladysmith where my wife had broken down. I was in the great Ser3R6 and had borrowed my mates rally car trailer.

    As it turned out the merc did not fit too well, and the trailer had negative nose mass! I found that as soon as I picked up over 70, the trailer started to sway. It was a pretty slow drive back, but then there was nothing unusual about an R6 going slowly.

    Other than that I have never experienced trailer sway, but with heavier loads I tend to keep to <100km or just over. There is also a rule that you drive down hills in the same gear that you would go up. So if you would go up Van Reenens in 4th, then go down in 4th as well. With a venter trailer or similar this is not too much of an issue, however with a car or ski boat on the back you need to tow pretty carefully.

    I have never had huge tow ball mass, but 100kgs seems like a good number.

  8. #48
    Join Date
    Nov 2010
    Location
    Somerset West
    Age
    61
    Posts
    2,124
    Thanked: 794

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by Henris View Post
    There is another way, that I have used.

    As soon as you feel the sway, then yank the steering left to right. But not at the same time as the trailer. The idea is to break the oscillation. So if the osculation is every 2 sec, then yank your steering every second.

    But, I recommend you play with this and make sure you can manage it.
    This could work, on the basis that the faster running trailer is kept "centred" long enough to activate the trailer brake and slow it down, but I'm going to take a raincheck on this method. This is going to take super big gunnies for me to pull off, and I don't have these.

  9. #49
    Join Date
    Mar 2020
    Location
    Potchefstroom
    Posts
    16
    Thanked: 17

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by stephenplumb View Post
    As it turned out the merc did not fit too well, and the trailer had negative nose mass! I found that as soon as I picked up over 70, the trailer started to sway. It was a pretty slow drive back, but then there was nothing unusual about an R6 going slowly.
    I also managed to load a negative nose mass once by accident, and the swaying also started at over 70 km/h.

    The experience provoked the following thoughts -

    It is as if the trailer steers itself like a pendulum, as if the weight shifts heen en weer, alternately compressing the leaf springs, which moves the axle a tiny bit backwards on the side that compresses and therefore steers the trailer. Road speed affects frequency, so at a rate the combination of the mass and the springs like to oscillate at, the swaying will keep going. Lowering speed lowers the frequency, bringing it under the Q of the system, stopping the oscillation.

    Loading more weight to the front shortens the pendulum and increases the resonant frequency, ideally to something that does not cause a problem.

  10. #50
    Join Date
    Oct 2011
    Location
    Midrand
    Age
    49
    Posts
    3,056
    Thanked: 1076

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by pseudonaam View Post
    I also managed to load a negative nose mass once by accident, and the swaying also started at over 70 km/h.

    The experience provoked the following thoughts -

    It is as if the trailer steers itself like a pendulum, as if the weight shifts heen en weer, alternately compressing the leaf springs, which moves the axle a tiny bit backwards on the side that compresses and therefore steers the trailer. Road speed affects frequency, so at a rate the combination of the mass and the springs like to oscillate at, the swaying will keep going. Lowering speed lowers the frequency, bringing it under the Q of the system, stopping the oscillation.

    Loading more weight to the front shortens the pendulum and increases the resonant frequency, ideally to something that does not cause a problem.
    Thats quite a physics heavy explanation. I have no considered it that deeply but the idea sounds plausible. I just stick with +ve nose weight now. I would assume that if one was approaching a resonant frequency, then the amplitude of the oscillation should increase suddenly? I guess thats when you find your face on your window sliding down the road, wondering where it all went wrong?

  11. #51
    Join Date
    Jul 2011
    Location
    Richards Bay
    Age
    37
    Posts
    564
    Thanked: 124

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    I tow a Gypsey Regal with a Nissan X-Trail with a gooseneck towbar. No stabalizers or fancy anti-sway tech.
    The only time the caravan swayed slightly is when I overtake a large 18 wheeler where the truck sucks me in, and when the caravan escapes that "suck", it sways a bit. I just give it some right foot and the car pulls the caravan straight again.

    I once went over 120 on a downhill and the caravan started to sway on it's own. But I tow between 100km/h and 120km/h with 120 being the absolute limit before the caravan becomes unstable and me feeling safe. Under 120, I have never experienced strange swaying issues while driving with that gooseneck.

    But now with the Pathfinder, I can tow comfortably at 150km/h....

    P.S Just kidding.

    Here is an interesting video I saw some time ago:

    Last edited by IcePick88; 2020/11/04 at 02:55 PM.
    2007 Nissan Pathfinder LE 2.5dCI 4x4
    2013 Nissan Xtrail 2.0dCi XE 2x4

  12. #52
    Join Date
    Oct 2011
    Location
    Midrand
    Age
    49
    Posts
    3,056
    Thanked: 1076

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by IcePick88 View Post
    I tow a Gypsey Regal with a Nissan X-Trail with a gooseneck towbar. No stabalizers or fancy anti-sway tech.
    The only time the caravan swayed slightly is when I overtake a large 18 wheeler where the truck sucks me in, and when the caravan escapes that "suck", it sways a bit. I just give it some right foot and the car pulls the caravan straight again.

    I once went over 120 on a downhill and the caravan started to sway on it's own. But I tow between 100km/h and 120km/h with 120 being the absolute limit before the caravan becomes unstable and me feeling safe. Under 120, I have never experienced strange swaying issues while driving with that gooseneck.

    But now with the Pathfinder, I can tow comfortably at 150km/h....

    P.S Just kidding.

    Here is an interesting video I saw some time ago:

    Overtaking a truck on a downhill is a big no-no with a caravan. It presents too much side area, and if you cannot get a good distance away from the truck you will get sucked in. Sounds like you had a lucky escape.

    With a low profile skiing boat or similar you will be pretty much unaffected, but with a high sided trailer you need to be very aware of overtaking big trucks.

    I would be happy to tow a venter at 120km/hr, but with something heavy on the rear, I like to keep to around 100km/hr or less.

  13. #53
    Join Date
    Mar 2020
    Location
    Potchefstroom
    Posts
    16
    Thanked: 17

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by stephenplumb View Post
    Thats quite a physics heavy explanation. I have no considered it that deeply but the idea sounds plausible. I just stick with +ve nose weight now. I would assume that if one was approaching a resonant frequency, then the amplitude of the oscillation should increase suddenly? I guess thats when you find your face on your window sliding down the road, wondering where it all went wrong?
    That would be extreme resonance!

    Luckily the Q factors of typical vehicles are quite low. Heinz’s explanation of the trailer picking up speed when it is plucked by the tow vehicle at the edges of the sway explains how the sway keeps going, despite being damped by resistances in the springs.

    There is however a certain rate at which a specific spring-mass combination likes to wiggle, look at how quickly an empty trailer bounces and how lazily a heavy laden one dances.

    By moving, the steering effects caused by the weight transfer feed back into the system. Lots of factors determine where the point of unstability begins, but the one we can directly control on the road is our speed, so that we don’t exceed it.

    From my limited experience with sway, the most prominent feeling was not the tow vehicle being jerked about, but rather the trailer walking from side to side and I could feel that effect slightly in the driver seat and see it clearly in the mirrors. It was a low frequency sway, at a rate of about one-two-left-one-two-right. That made me realize the trailer steering itself as weight is displaced is a major contributor.

    Just some background on what was towed - 2.4m tralieswa loaded with 11 steel tables, 46 chairs, beer kegs, water cans, large gas cylinder and some miscellaneous heavyish equipment. I estimate the total towed mass around 1.2 to 1.3 tons.

    Anyway, I don’t like going fast when towing, especially as my trailer is unbraked. I try to feel how the vehicle likes to go and just drive it like that. Driving like nothing is on the hitch gives 7.5 km per liter, taking things a tad easier gives 10.5 and above, exactly the same as when not towing.
    Last edited by pseudonaam; 2020/11/04 at 03:57 PM. Reason: Typo...

  14. #54
    Join Date
    Jul 2011
    Location
    Richards Bay
    Age
    37
    Posts
    564
    Thanked: 124

    Default Re: Trailer & Caravan Sway - Tips, Tricks, Reasons & Recommendations

    Quote Originally Posted by stephenplumb View Post
    Overtaking a truck on a downhill is a big no-no with a caravan. It presents too much side area, and if you cannot get a good distance away from the truck you will get sucked in. Sounds like you had a lucky escape.

    With a low profile skiing boat or similar you will be pretty much unaffected, but with a high sided trailer you need to be very aware of overtaking big trucks.

    I would be happy to tow a venter at 120km/hr, but with something heavy on the rear, I like to keep to around 100km/hr or less.
    No. Did not overtake a truck on a downhill.

    Overtaking the truck and going downhill was two separate instances.

    But I do like sitting at 110km/h. My car is happiest there. Right on the torque when I need it. Both the X-Trail and Pathfinder.
    2007 Nissan Pathfinder LE 2.5dCI 4x4
    2013 Nissan Xtrail 2.0dCi XE 2x4

Page 3 of 3 FirstFirst 1 2 3

Similar Threads

  1. Which off road caravan or off road trailer is the best?
    By Dirk in forum Camping, Fridges, Accessories
    Replies: 53
    Last Post: 2017/10/06, 10:54 AM
  2. Trailer or Caravan
    By TiaanS in forum Camping, Fridges, Accessories
    Replies: 33
    Last Post: 2017/09/18, 05:30 PM
  3. Reversing with a trailer behind your 4x4?
    By Big Hilux in forum Vehicle & Technical Chat - General
    Replies: 44
    Last Post: 2013/02/04, 12:51 PM
  4. Camping Trailer Hire - Recommendations
    By SimonB in forum Camping, Fridges, Accessories
    Replies: 8
    Last Post: 2009/06/09, 10:02 AM
  5. Bush tested Conqueror Commander Offroad Caravan
    By Dirk in forum Camping, Fridges, Accessories
    Replies: 2
    Last Post: 2007/01/03, 06:18 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •