Towing reverberation

Solent Ribman · 17 June 2009, 21:17

Our 6m Ribeye on single axle braked Bramber Trailer has a constant reverbaration [only description I can think of] that runs through the vehicle when towing. It's a sort of wave feel, as though the trailer is trying to push the car and the car is then trying to stop it going forward. Any thoughts from anyone what is causing this? Is it normal - being relatively new to distance towing, I don't have any experience to call on. Is there a cure?

JSP · 17 June 2009, 22:31

I've had a similar ( I think) experiance with a trailer that had to much weight on the hitch.

neilda · 18 June 2009, 00:08

Is there an inexpensive way to check that the wheels are aligned on the trailer?

Andy_Rs600 · 18 June 2009, 08:50

Is wht you are describing up and down, left and right or forward and backward?

Up and down tends to be nose weight, often too little, but sometimes too much.
Side to side is also often too little nose weight, improper axle alignment or topo much windage forward on the boat if it only happens at speed.
Forward/backwards sometimes happens with a worn damper on your overrun brakes, but normally you'll start hearing the banging when you brake first.

Solent Ribman · 18 June 2009, 12:32

I did think there may be an issue one way or another with the hitch weight, but to be honest I would have thought with 300kg of Yam on the back it would be hitch light!

JSP · 18 June 2009, 12:36

Quote:

Originally Posted by Solent Ribman

I did think there may be an issue one way or another with the hitch weight, but to be honest I would have thought with 300kg of Yam on the back it would be hitch light!

Easiest guide is to stick the Jockey wheel on some bathroom scales, not perfect but gives you an idea.

jyasaki · 18 June 2009, 15:12

A look in the mirror while running should tell you if the trailer is actually swaying on you. Too little tongue weight will cause the rear of the trailer to hunt. Too much usually won't cause a problem for the trailer, but lightens the front wheel weight on the tow vehicle (steering gets weird; also causes excessive squat in the back of the TV.)

For the axle alignment, I usually just tape measure from the a known point to a point on the axle: back of the frame rails to the rear spring mount, for example. Then check that the axle is mounted to the center of each spring.

How are your brakes activated? Surge coupler?

I've had a similar problem with hydraulic surge brakes; something set the trailer to surging forward, activating the brakes, which then pulled back, releasing them, then it bounced forwards again starting the cycle over.

Adjusting the brakes a bit looser corrected the problem.

Luck;

jky

jambo · 18 June 2009, 15:38

[

I've had a similar problem with hydraulic surge brakes; something set the trailer to surging forward, activating the brakes, which then pulled back, releasing them, then it bounced forwards again starting the cycle over.

Adjusting the brakes a bit looser corrected the problem.

Luck;

jky [/QUOTE]

I have the same problem as jky and have just had to live with it unfortunately.

J

CJL · 18 June 2009, 21:10

On small dinghy trailers I've had problems at ahem slightly higer speeds than 60mph but getting the wheels balanced sorted it.

Not sure if it will solve your problem but it may help.

C

Tino · 23 June 2009, 08:53

Quote:

Originally Posted by Solent Ribman

I did think there may be an issue one way or another with the hitch weight, but to be honest I would have thought with 300kg of Yam on the back it would be hitch light!

You might be too light on the hitch...which causes tail swing. the weight on the ball should be around 50kgs depending on the car..A little more for a big 4x4. Giving you that snaking side to side feeling followed by a jack-knife if you are not very careful.

I suppose the trailer is a 4 wheeler...check the hitch height...If this is wrong this might be causing the front or back axle to bounce off the ground which will give you a wave feeling.. up and down.

However what you describe is more fore and aft pushing/pulling would suggest that the damper (a shock absorber) in the hitch is knackered. This allows the override braking system to spring back and forward...giving you that fore and aft bumping feeling.

Rigaud · 24 June 2009, 13:52

Quote:

Originally Posted by Tino

You might be too light on the hitch...which causes tail swing. the weight on the ball should be around 50kgs depending on the car..A little more for a big 4x4. Giving you that snaking side to side feeling followed by a jack-knife if you are not very careful.

I suppose the trailer is a 4 wheeler...check the hitch height...If this is wrong this might be causing the front or back axle to bounce off the ground which will give you a wave feeling.. up and down.

However what you describe is more fore and aft pushing/pulling would suggest that the damper (a shock absorber) in the hitch is knackered. This allows the override braking system to spring back and forward...giving you that fore and aft bumping feeling.

Actually your supposed to have 10% of your towing weight on the hitch to make certain your properly balanced. In other words as an example if your boat/trailer package weighs in at 3000lbs then you should have approx. 300lbs on the hitch. If you end up with 100-150lbs on the hitch then your not balanced properly.

Tino · 25 June 2009, 15:51

Quote:

Originally Posted by Rigaud

Actually your supposed to have 10% of your towing weight on the hitch to make certain your properly balanced. In other words as an example if your boat/trailer package weighs in at 3000lbs then you should have approx. 300lbs on the hitch. If you end up with 100-150lbs on the hitch then your not balanced properly.

your 10 % rule is only right for trailer combos of between 300 - 500kgs.

For a 1000kgs trailer there is NO WAY you should have 100kgs on the ball.

10% of a large trailer combo is FAR TOO much weight on a towing bracket. I have regularly towed 3.5 tonnes....which if we used your 10% would mean that the towing bracket of my car would have 350kgs downward force which is more that 400% of the max permitted by the manufacturer. It would be the equivalent of having. 4 really big people in the boot of your car which would make it very unstable and I'd think the front wheels might actually lift off the ground if you managed to drive far enough to reach a bump!!

jyasaki · 25 June 2009, 16:10

The figures I've seen for tongue weight usually specify between 5 to 15 percent. Most cite 7 to 10 percent, but a few say 10 to 15, and a very few 5 to 10.

If you have that percentage and the tongue weight causes problems with the tow vehicle, you should be looking at a weight distributing hitch.

Problem is that simply lightening up the tongue weight may cause instability in the trailer at speed.

jky

Tino · 25 June 2009, 16:36

Quote:

Originally Posted by jyasaki

The figures I've seen for tongue weight usually specify between 5 to 15 percent. Most cite 7 to 10 percent, but a few say 10 to 15, and a very few 5 to 10.

If you have that percentage and the tongue weight causes problems with the tow vehicle, you should be looking at a weight distributing hitch.

Problem is that simply lightening up the tongue weight may cause instability in the trailer at speed.

jky

The manual for my current car specifies that the maximum weight on a tow hitch is 100kgs and the max legal towing capacity is 3500kgs. If I was to use any of your rules the weight on the ball would be grossly outside the maximum allowed.
I have never used a Weight Distributing hitch and have never had a problem!

Rigaud · 25 June 2009, 20:52

Quote:

Originally Posted by Tino

your 10 % rule is only right for trailer combos of between 300 - 500kgs.

For a 1000kgs trailer there is NO WAY you should have 100kgs on the ball.

10% of a large trailer combo is FAR TOO much weight on a towing bracket. I have regularly towed 3.5 tonnes....which if we used your 10% would mean that the towing bracket of my car would have 350kgs downward force which is more that 400% of the max permitted by the manufacturer. It would be the equivalent of having. 4 really big people in the boot of your car which would make it very unstable and I'd think the front wheels might actually lift off the ground if you managed to drive far enough to reach a bump!!

Different regulations for different country's I guess but yep and I have a 10,000 lbs towing package on my truck and NOT a car. My max. capacity tongue weight is 1000 lbs for that particular reason. Just my truck alone weighs in at 5300 lbs so not to worry. Here you can not tow the weights you mentioned with a car and even small v6 SUV's are limited to about 3500 lbs max witch is why I mentioned the 10%.

By the way, are you certain it's KGS and not LBS for the weight because 3500kgs would be over 7,000 lbs and I would love to see a car pulling that much weight.

fred bolton · 25 June 2009, 22:53

The guys trailer is SINGLE axle nose weight is limited to the manufacturers limits and will probably be between 50 and 100 kgs If you cannot lift the hitch it is too heavy. I would guess 75kg would be the ideal nose weight which maybe 10% of your outfit. However Brits do not use a 10% rule as has already been said even Land rovers can tow 3500 tons but you would NEVER stick 350kg on the towball

Tino · 26 June 2009, 07:31

Quote:

Originally Posted by Rigaud

Different regulations for different country's I guess but yep and I have a 10,000 lbs towing package on my truck and NOT a car. My max. capacity tongue weight is 1000 lbs for that particular reason. Just my truck alone weighs in at 5300 lbs so not to worry. Here you can not tow the weights you mentioned with a car and even small v6 SUV's are limited to about 3500 lbs max witch is why I mentioned the 10%.

By the way, are you certain it's KGS and not LBS for the weight because 3500kgs would be over 7,000 lbs and I would love to see a car pulling that much weight.

Merc ML280CDI 4 x 4 7 speed Automatic (3l Diesel) tows 3500kgs with ease. I suppose you would call it an suv but it drives like a car with the comfort of your best lounge chair and will tow a 3500 trailer up a slipway! It weighs 2250kgs = 4950lbs

jyasaki · 26 June 2009, 15:22

Quote:

Originally Posted by Tino

The manual for my current car specifies that the maximum weight on a tow hitch is 100kgs and the max legal towing capacity is 3500kgs.

You do realize that those are two unrelated specs, right?

Quote:

I have never used a Weight Distributing hitch and have never had a problem!

Doesn't necessarily mean that everything is hunky-dory. It only takes one incident to negate that statement.

jky

Tino · 26 June 2009, 15:37

Quote:

Originally Posted by jyasaki

You do realize that those are two unrelated specs, right?

Doesn't necessarily mean that everything is hunky-dory. It only takes one incident to negate that statement.

jky

Yep...totally unrelated. Weight on ball = MAX 100kgs and the max gross weight of braked trailer 3500kgs. The manufacturer of the vehicle, the manufacturer of towing bracket and the manufacturer trailer specify that the max nose weight is 100kgs. I guess that they cant all be wrong and imagine that they are better qualified than me!

I have towed trailers like that literally thousands of kilometers...including Dublin - Lisbon and back many times ( almost 5000 km round trip) and never had the slightest problem.

cheers

Rigaud · 26 June 2009, 22:03

Quote:

Originally Posted by Tino

Merc ML280CDI 4 x 4 7 speed Automatic (3l Diesel) tows 3500kgs with ease. I suppose you would call it an suv but it drives like a car with the comfort of your best lounge chair and will tow a 3500 trailer up a slipway! It weighs 2250kgs = 4950lbs

Ah, that explains it.

So your pretty much equiped as I am just different brand.

Most SUV's with that size engine are gas and not that great for towing heavy loads over here.

We see too many towing tent trailers, utility, or boats and just horribly balanced. Many on the road you can clearly see the trailer swaying side to side or even shaking all over the road. People don't verify the bearings and other maintenance plus sometimes I swear they must have 5lbs on the tongue.