WDH, Air Bags and/or Increased rear Spring Capacity.

iana · Guru

WDH, Air Bags and/or Increased rear Spring Capacity.

travelyounger · Guru

oldbloke wrote:
Yobarr, you just can't admit you made a mistake getting a rear end upgrade that does very little if anything to correct the problem of less weight on the ront steering axles.

If your sooo, good show us, don't say you don't have time. You keep telling us your an expert.

Why is it a mistake take my dmax for instance I bought new in 2017 and had a aluminium canopy fitted and a fridge and toolbox in car in front of rear axle . The Five leaf springs had nearly turn backwards and that was even before loading my boat and van.I do use a WDH which does transfer some weight to front wheels but minimal so the suspension upgrade was the only solution WDH are not the weight solving answer as I tried with and without with very little difference to braking and weight transfer

Cheers

Peter_n_Margaret · Guru

If the rear suspension is stiffened without a corresponding change to the front, the under steer/over steer characteristics of the vehicle will change. That can lead to dangerous handling.
Cheers,
Peter

oldbloke · Guru

Peter_n_Margaret wrote:
If the rear suspension is stiffened without a corresponding change to the front, the under steer/over steer characteristics of the vehicle will change. That can lead to dangerous handling.
Cheers,
Peter

Thankyou Peter, also thinking along those lines.

"Five leaf springs had nearly turn backwards".

Just guessing that Ute is way over loaded.

yobarr · Guru

Peter_n_Margaret wrote:
If the rear suspension is stiffened without a corresponding change to the front, the under steer/over steer characteristics of the vehicle will change. That can lead to dangerous handling.
Cheers,
Peter

You are,of course,quite right with that assertion,Peter.If you are referring to John's (Travelyounger) car,he has had a major upgrade to 3600kg GVM and 7000kg GCM on his DMax.In the past,John and I had some spirited interactions,as he had misunderstood the apparent capabilities of his car,but that was subsequently sorted,and he now knows that he can run legal at around 6600kg (+/- )all up.Back to understeer/oversteer,as mentioned in your post.What many people do not realise is that the addition of a WDH adds around 40kg to the car's rear axle,as well as increasing TBO,(Towball overhang) so in one smart move they've not only increased their rear axle weight,they've also made the vehicle more susceptible to the effects of yaw,so less safe.Very clever. THEN you get those who don't understand the effects of using a WDH,and tension it waaaay up.This can result in the transfer of too much weight off the car's rear axle,and the resulting oversteer.Rather than try to make a car do things for which it never was designed,it is better to buy a suitable car in the first place,and leave the WDH in the shed. Cheers

iana · Guru

"Rather than try to make a car do things for which it never was designed, it is better to buy a suitable car in the first place, and leave the WDH in the shed." A sensible statement.

Are We Lost · Guru

Buy the right vehicle? Sure, great advice. But some people don't want a truck.

Back in Post #2 I suggested we are focused too much on the easily measurable static loads. A WDH does nothing to handling while parked on the weighbridge. What matters is the open road.

Have a close look at the video posted by Peter_n_Margaret where the front wheels of the towing vehicle become airborne. An extreme example, but it is ueful to note that both ute and van appear to be travelling fairly level. So, while parked it would appear to be well set up. The undulation in the road is not noticeable in the video, and the OKA hardly bounces when going over the same spot.

At the moment the wheels become airborne, can anyone suggest what the actual weight on the towball would be? 1,000kg would not come close to lifting the front. Can you imagine what it would do to handling even before the front wheels became airborne? If cornering at the time, the handling dynamics would be changed in an instant, then back again next instant.

The same applies with braking. Just when you need those front brakes most, the weight transfer from the van to the towball must be huge, resulting in less traction on the essential steering wheels.

Now consider if a WDH is fitted. The normal guideline is to adjust a WDH to return 50% of the load back to the front wheels. BUT ....

When more weight is loaded onto the towball and the rear end sags, the WDH tensions more, thus transferring a greater percentage of weight to the front. So, when towball suddenly increases, the percentage of load returned to the front wheels increases. This is how a WDH does such a great job at reducing porpoising, and therefore making a marked difference to recovering lost handling and braking performance.

So, don't just think about static weights while the van is parked. Don't think about the static figure of 50-100kg back to the front wheels. It's what happens on the road that matters.

-- Edited by Are We Lost on Friday 17th of December 2021 12:52:00 PM

KJB · Guru

Are We Lost wrote:
Buy the right vehicle? Sure, great advice. But some people don't want a truck.

Back in Post #2 I suggested we are focused too much on the easily measurable static loads. A WDH does nothing to handling while parked on the weighbridge. What matters is the open road.

Have a close look at the video posted by Peter_n_Margaret where the front wheels of the towing vehicle become airborne. An extreme example, but it is ueful to note that both ute and van appear to be travelling fairly level. So, while parked it would appear to be well set up. The undulation in the road is not noticeable in the video, and the OKA hardly bounces when going over the same spot.

At the moment the wheels become airborne, can anyone suggest what the actual weight on the towball would be? 1,000kg would not come close to lifting the front. Can you imagine what it would do to handling even before the front wheels became airborne? If cornering at the time, the handling dynamics would be changed in an instant, then back again next instant.

The same applies with braking. Just when you need those front brakes most, the weight transfer from the van to the towball must be huge, resulting in less traction on the essential steering wheels.

Now consider if a WDH is fitted. The normal guideline is to adjust a WDH to return 50% of the load back to the front wheels. BUT ....

When more weight is loaded onto the towball and the rear end sags, the WDH tensions more, thus transferring a greater percentage of weight to the front. So, when towball suddenly increases, the percentage of load returned to the front wheels increases. This is how a WDH does such a great job at reducing porpoising, and therefore making a marked difference to recovering lost handling and braking performance.

So, don't just think about static weights while the van is parked. Don't think about the static figure of 50-100kg back to the front wheels. It's what happens on the road that matters.

-- Edited by Are We Lost on Friday 17th of December 2021 12:52:00 PM

Correctly calibrated/matched springs and shock absorbers negate so called "porpoising " ........that is what they are all about - carrying the weight and controlling the speed of compression and rebound.....KB

Peter_n_Margaret · Guru

No, hanging 300kg plus a metre or more behind the rear axle is the problem. Dampers were never designed to control that.
Cheers,
Peter

KJB · Guru

Peter_n_Margaret wrote:
No, hanging 300kg plus a metre or more behind the rear axle is the problem. Dampers were never designed to control that.
Cheers,
Peter

So the load is inappropriate for the existing suspension - change the load or change the suspension/vehicle - in other words , "if the load requires a truck , get one..(whether you want it or not you need it..) - otherwise change the load to suit your vehicle ....... KB

travelyounger · Guru

oldbloke wrote:
Peter_n_Margaret wrote:
If the rear suspension is stiffened without a corresponding change to the front, the under steer/over steer characteristics of the vehicle will change. That can lead to dangerous handling.
Cheers,
Peter
Thankyou Peter, also thinking along those lines.

"Five leaf springs had nearly turn backwards".
Just guessing that Ute is way over loaded.

Hi 500 kg on a payload of around 1000 kg is no way overloaded

cheers

oldbloke · Guru

travelyounger wrote:
oldbloke wrote:
Peter_n_Margaret wrote:
If the rear suspension is stiffened without a corresponding change to the front, the under steer/over steer characteristics of the vehicle will change. That can lead to dangerous handling.
Cheers,
Peter
Thankyou Peter, also thinking along those lines.

"Five leaf springs had nearly turn backwards".
Just guessing that Ute is way over loaded.
Hi 500 kg on a payload of around 1000 kg is no way overloaded
cheers

Then how do you explain "Five leaf springs had nearly turn backwards".

Poor design or fault springs.?

oldbloke · Guru

Well, I'm puzzled. According to yobarr, Haymen Reece have been decieving their customers. They are wrong and he is right.

I'll believe Haymen Reece I think.

yobarr · Guru

oldbloke wrote:
Well, I'm puzzled. According to yobarr, Haymen Reece have been decieving their customers. They are wrong and he is right.

I'll believe Haymen Reece I think.

You certainly are puzzled,as NEVER have I said that HR are deceiving their customers.All I have ever done is suggest that their illustrations are designed to cater for those people who struggle to understand even basic physics,but it seems that such a simple explanation still is beyond the comprehension of some? C'est la vie. "Zero" ball weight on a PIG trailer? Yeah,right.Cheers

oldbloke · Guru

yobarr wrote:
oldbloke wrote:
Well, I'm puzzled. According to yobarr, Haymen Reece have been decieving their customers. They are wrong and he is right.

I'll believe Haymen Reece I think.
You certainly are puzzled, SPACE as NEVER have I said that HR are deceiving their customers. SPACE All I have ever done is suggest that their illustrations are designed to cater for those people who struggle to understand even basic physics, SPACE but it seems that such a simple explanation still is beyond the comprehension of some? C'est la vie. "Zero" ball weight on a PIG trailer? Yeah,right. SPACE Cheers

Since the example you refer to is fitted with a fully adjusted WDH the ball weight is distributed to the front axles of the tow vehicle and the van axles it is not unreasonable to expect 0 or near to 0 on the ball. (BOTTOM LINE) It is an example. Or are you unable to read a simple set of tables. YOU DIDN'T NOTICE THAT THE TBW IS TRANSFERED TO THE REAR AXLE, RIGHT? (MIDDLE LINE) It can't be on both axle and the TB. We both know it is transferred through the Axle to the ground. Too simple for you. Eh.

Cheers

HR WDH display.jpg

-- Edited by oldbloke on Friday 17th of December 2021 11:11:02 PM

-- Edited by oldbloke on Friday 17th of December 2021 11:12:55 PM

yobarr · Guru

oldbloke wrote:
yobarr wrote:
oldbloke wrote:
Well, I'm puzzled. According to yobarr, Haymen Reece have been decieving their customers. They are wrong and he is right.

I'll believe Haymen Reece I think.
You certainly are puzzled, SPACE as NEVER have I said that HR are deceiving their customers. SPACE All I have ever done is suggest that their illustrations are designed to cater for those people who struggle to understand even basic physics, SPACE but it seems that such a simple explanation still is beyond the comprehension of some? C'est la vie. "Zero" ball weight on a PIG trailer? Yeah,right. SPACE Cheers
Since the example you refer to is fitted with a fully adjusted WDH the ball weight is distributed to the front axles of the tow vehicle and the van axles it is not unreasonable to expect 0 or near to 0 on the ball. It is an example. Or are you unable to read a simple set of tables. Too simple for you. Eh.
Cheers

Surely it can't be the case that you still haven't learned that a WDH does NOT change towball weight? Never has,never will. If,after all the time and effort that I have put in to proving this, explaining exactly what happens when a WDH is tensioned,having others understand and accept that fact,you still don't understand,then there is little more I can do to help you.Sorry.Back to sleep.Cheers

-- Edited by yobarr on Friday 17th of December 2021 11:41:06 PM

travelyounger · Guru

oldbloke wrote:
travelyounger wrote:
oldbloke wrote:
Peter_n_Margaret wrote:
If the rear suspension is stiffened without a corresponding change to the front, the under steer/over steer characteristics of the vehicle will change. That can lead to dangerous handling.
Cheers,
Peter
Thankyou Peter, also thinking along those lines.

"Five leaf springs had nearly turn backwards".
Just guessing that Ute is way over loaded.
Hi 500 kg on a payload of around 1000 kg is no way overloaded
cheers
Then how do you explain "Five leaf springs had nearly turn backwards".

Poor design or fault springs.?

Poor design I would have to say as most utes do upgrades to handle off road conditions and towing or carrying heavy weights and Im sorry to say but its been happening since I can remember

cheers

norto · Member

Take you vehicle to a reputable suspension expert and get him to fix it. Air bags may be a cheap alternative

to doing the springs etc. Once you put a caravan on the back all the handling characteristics of your vehicle will change, not just under/oversteer

oldbloke · Guru

Yes, yobarr you continue to blab.
Yes it stays the same but is DISTRIBUTED so is shown elsewhere. As it says. But you refuse to admit your error. Blinded by your own arrogance.

travelyounger · Guru

norto wrote:
Take you vehicle to a reputable suspension expert and get him to fix it. Air bags may be a cheap alternative
to doing the springs etc. Once you put a caravan on the back all the handling characteristics of your vehicle will change, not just under/oversteer

Agree but not air bags on leaf springs

cheers

oldbloke · Guru

Hi 500 kg on a payload of around 1000 kg is no way overloaded

cheers

Then how do you explain "Five leaf springs had nearly turn backwards".

Poor design or fault springs.?

Poor design I would have to say as most utes do upgrades to handle off road conditions and towing or carrying heavy weights and Im sorry to say but its been happening since I can remember

cheers

Perhaps as a result of cost cuts or a desire to give passengers a better ride. Very difficult to have a high payload and still have a soft ride for the passengers. Heavy springs generally equal hard ride. Although I'm sure there are ways. (Expensive)

-- Edited by oldbloke on Saturday 18th of December 2021 08:21:46 AM

yobarr · Guru

oldbloke wrote:
Yes, yobarr you continue to blab.
Yes it stays the same but is DISTRIBUTED so is shown elsewhere. As it says. But you refuse to admit your error. Blinded by your own arrogance.

Surely you cannot be serious here? "Stays the same but is DISTRIBUTED so is shown elsewhere" you write.What a load of rubbish.Below you will see a definition for "distribute" showing that when something is "distributed" it is "separated into parts". Surely even you can understand (?) that it is impossible for something to be "separated in to parts" AND "stay the same"? For the 700th (+/-) time,a WDH DOES NOT change towball weight. As I have previously said,the chart provided by you,which has been provided MANY times before by other members,Clarky being one,is designed to assist people with little knowledge of physics to understand the workings of a WDH.Seems that no matter how simplified it is,some still cannot or do not WANT to understand.Please refer to my post from 10.21pm yesterday,which is direct from the HR website.You may like to contact them to offer your assistance,and to let them know that after 60 years in business,they still don't know what they're talking about? In case you already have forgotten a WDH DOES NOT change towball weight.Never has,never will. Cheers

P.S You may notice that my post contains no insults, although I must admit that I considered suggesting that some are blinded by their ignorance.

-- Edited by yobarr on Saturday 18th of December 2021 08:52:03 AM

yobarr · Guru

travelyounger wrote:
norto wrote:
Take you vehicle to a reputable suspension expert and get him to fix it. Air bags may be a cheap alternative.
to doing the springs etc. Once you put a caravan on the back all the handling characteristics of your vehicle will change, not just under/oversteer
Agree but not air bags on leaf springs
cheers

You're right John.Airbags plus leaf springs equals bent chassis.Cheers

-- Edited by yobarr on Saturday 18th of December 2021 09:05:25 AM

oldbloke · Guru

"WDH DOES NOT change towball weight.Never has,never"

Correct, it is the same. But it is distributed to other axles. And that is what the graphic shows and web site says.

And BTW, I did not insult you. Just stated how it is.

oldbloke · Guru

"WDH DOES NOT change towball weight.Never has,never"

Correct, it is the same. But it is distributed to other axles. And that is what the graphic shows and web site says.

And BTW, I did not insult you. Just stated how it is.

yobarr · Guru

oldbloke wrote:
"WDH DOES NOT change towball weight.Never has,never"

Correct, it is the same. But it is distributed to other axles. And that is what the graphic shows and web site says.

And BTW, I did not insult you. Just stated how it is.

Neil,you are either absolutely lost in the WDH wilderness,or you are just being difficult. How on earth can towball weight be "distributed to other axles" AND at the same time "stay the same".It cannot be in two places at once.If it's been "distributed",by definition,it's it has been moved. A WDH does NOT move towball weight.Never has.Never will.Nah,I think that you're just being stupid now.Cheers

iana · Guru

Well folks, to throw a spanner in the works, my thoughts are, is that a WDH does alter the downward force of the trailer coupling. It will depend entirely on how much the rear of the tow vehicle sags when the trailer is coupled, to when the WDH is adjusted so that the trailer is level.
Any rotation about the central axis will change the center of gravity, moving the center of gravity fore or aft will alter the way the weight is distributed between the two, or even three points of the trailer (you have never seen a trailer fall back on its ar-e)?

oldbloke · Guru

yobarr wrote:
oldbloke wrote:
"WDH DOES NOT change towball weight.Never has,never"

Correct, it is the same. But it is distributed to other axles. And that is what the graphic shows and web site says.

And BTW, I did not insult you. Just stated how it is.
Neil, SPACE you are either absolutely lost in the WDH wilderness, SPACE or you are just being difficult. How on earth can towball weight be "distributed to other axles" AND at the same time "stay the same". SPACE It cannot be in two places at once. SPACE If it's been "distributed", SPACE by definition, SPACE it's it has been moved. A WDH does NOT move tow SPACE ball weight. SPACE Never has. SPACE Never will. SPACE Nah, SPACE I think that you're just being stupid now. SPACE Cheers

Oh dear you really are lost Yobarr.

I will try to assist you with a very, very simple example.

I have 2 buckets

I place both buckets in the boot of my car.

Bucket 1 has 20 kg of sand in it

Bucket 2 is empty

Sooo, the total weight of sand is 20kg in the boot

I pour from bucket 1 10kg of sand into bucket 2

Now both buckets have 10kg of sand. Note: 10 + 10 = 20kg

I move bucket 1 to the rear seat =10kg

I move bucket 2 to the front seat =10kg

The 20 kg has been distributed into 2 buckets over 2 locations and surprise, surprise the total weight is unchanged at 20kg of sand added to the car. No longer in the boot but on the front and rear seats.

And that my friend is exactly what Hayman Reece is displaying in the graphic and saying on their web site.

But you already know that, right?

Cheers mate.

-- Edited by oldbloke on Saturday 18th of December 2021 11:22:01 AM

yobarr · Guru

iana wrote:
Well folks, to throw a spanner in the works, my thoughts are, is that a WDH does alter the downward force of the trailer coupling. It will depend entirely on how much the rear of the tow vehicle sags when the trailer is coupled, to when the WDH is adjusted so that the trailer is level.
Any rotation about the central axis will change the center of gravity, moving the center of gravity fore or aft will alter the way the weight is distributed between the two, or even three points of the trailer (you have never seen a trailer fall back on its ar-e)?

Ian,could I respectfully suggest that you too approach Hayman Reece and let them know that they've been doing things wrong for 60 years.See screenshot below.This topic has been covered many times on this forum,and I have fully explained the facts to the non-believers,all of whom,with one notable exception,have come to understand that a WDH DOES NOT change towball weight.If you care to search on this site for "Effects of WDH" or something similar,you will find much helpful information.Cheers

DIRECT FROM THE HAYMAN REECE WEBSITE.

-- Edited by yobarr on Saturday 18th of December 2021 11:35:49 AM

Are We Lost · Guru

C'mon you two. Like two school kids seeing who can reach further up the wall in the latrine.

Picking up on an earlier post, Oldbloke said .
"Since the example you refer to is fitted with a fully adjusted WDH the ball weight is distributed to the front axles of the tow vehicle and the van axles it is not unreasonable to expect 0 or near to 0 on the ball. It is an example. Or are you unable to read a simple set of tables. Too simple for you. Eh."

Sorry Oldbloke, its you who misunderstood the chart. The towball weight is still 220kg, not 0. The chart just does not show it. (I think your later posts seem to accept that).

What the chart is showing is the weight on the wheels. Only the first line shows towball weight because that is on the jockey wheel. After the van is connected, the towball weight is ignored, and is certainly not zero and should never be zero. But while Yobarr noted that zero weight on the ball was a ludicrous situation, he did not look further.

And Yobarr is correct that the ball weight does not change with a WDH, which is as stated by HR.

Im sure others will be confused with that chart as well. Did that come from Hayman Reese?

Also, I believe the example shows a WDH that has been over-tensioned. From a relatively modest towball weight of 220kg, they have taken 290kg off the rear axle, and put 230 on the front. A bit excessive in my opinion.

By the way . Its spelt Hayman Reese.

-- Edited by Are We Lost on Saturday 18th of December 2021 11:39:34 AM