Thread: Disco 3 S & Hayman Reese weight distribution hitch

Hi Gypsy Pete,
Welcome to the forum.

You have raised a very controversial question. I suggest that you raise it in the D3 Zone (in the Pinnacles).
Edit: Wow, already moved. Thanks Mods. :-)


I also want to tow using my D3 with coil suspension. However, I was unhappy with the loss of departure angle & low towball height with the LR towhitch. As a result, I have bought a Mitchell Bros towhitch receiver (rated for 350kg towball load & 3500kg tow load). It is also suitable for using weight distribution hitches (WDH) (although I would hesitate to use them on D3s with airbag suspension). The Mitchell Bros tow hitch receiver, does NOT compromise departure angle (unlike the Hayman-Reese towbar).

I have yet to fit the Mitchell Bros bar, but will be testing it without WDHs first.

Do you KNOW that you will need WDH with the D3, or is it a case of "I have always used them"?

What unit are you planning to tow with the D3?

HTH,

Someone on the D3 site used a WDH on a coiler D3 but it the DSC kept cutting in when cornering. Not sure why this should be. IF LR are saying could cause damage rather than it could be a safety issue it would appear to confirm the suspision that the LR tow hitch is too weak to take the torsional loads of a WDH?
As bushwander says the engineer who approved the Mitchell Bros hitch said the hitch would take the load of a WDH.
It will be interesting to see how the Mitchel Bros hitch goes with air suspension and a WDH.

Fellas
CaverD3, by saying - "the suspicion that the LR tow hitch is too weak to take the torsional loads of a WDH" brings up an interesting point.

I have a reasonable general knowledge of things mechanical, but I don't know what he means by "torsional loads" (in this context).

I'll bet I'm about the same as 99% of LR/Disco owners.
I know what meant by-
Tare
GVM
GCM
Max towing capacity
Max ball download etc
And I understand the basic idea behind WDH's. Transfering weight from the rear axle to the front axle.
But I have never come across any detailed explainations of the physics involved.
For my ( and 99% of LR/Disco owners) benefit, is there anybody out there, who can either
1) point me in the direction of articles (with diagrams/pretty pictures) that explain the physics/maths/engineering behind WDH's, or
2) explain the above directly here on this post. Note: I'm quite happy with physics and maths providing you don't get into quantum physics or somesuch, and have some diagrams.
Thanks John
PS If someone out there can come up with a simple, easy-to-understand explanation of all this (as above) it could be put in as a permanent feature.
I'm sure that there'd be plenty of LR owners who'd refer to it.

I have been using the Mitchell Brothers hitch since it came out, towing a Golf Outback. So far it has proven to be a superb unit. I do not use the WDH and use a standard tongue and ball, which gives me the normal pre-hitching height for the van when all connected up. The rear of the D3 drops about 5mm when connected, with no difference in front measurements.

Have a complete heavy duty HR WDH for sale if anyone is interested - as new.

See the thread:

http://www.aulro.com/afvb/d3-zone/50...disco-3-a.html

where this point was thrashed out ad-nausem ......

It was mainly to do with EAS D3's, but some of the points (diagrams etc) would apply to a coiler.

Cheers,

Gordon

CaverD3,
I think that the activation of DSC would be independent of whether a WDH is employed or not.

What DSC does (by black magic, I think) is to determine when the D3 is outside the stability limits (say when cornering at speed). It then activates to bring the vehicle back within those limits.

One can imagine, that "pushing" from a trailer when cornering may also cause the DSC to be activated & act to bring it back within "limits".

Best Wishes,

Thanks Peter. I've been towing a 17 foot single axle caravan and have so far had no problems. I don't go off road so departure angle is not a problem. Its just that LR put the wind up me by just advising against using the WDH without being willing to tell me why. Now, I'm trying to find out. Is there a chance that the LR hitch will just fail and my caravan, complete with WDH will go wandering off to the side of the road?

Hi Again Gypsy_Pete,
You're not the only one that LR doesn't give reasons to. In the lack of that, NONE of us can be sure of the consequences.

I SUSPECT that their reasoning is mainly to do with the air bag suspension, but in their wisdom, LR don't elaborate.

I think that LR is generally conservative in the performance limits of its vehicles. This helps stop the "but you said that this would be OK" liability issues.

All I can say, if you find that you don't need a WDH, don't use one.

Enjoy your travels,