Modified Hitch

[wardh]

Hi Members

The project to modify the hitch on my D3 coiler is complete, the main purpose for the modification was to have some peace of mind from the fear of the receiver parting company with the vehicle as there has been reports of this happening.

I cannot take full credit for the idea as it was done by another member but I did alter the build slightly.

I elected to fabricate the box section out of 50mm wide x 6mm thick flat steel as I could not obtain box section in a suitable wall thickness. as it turned out it was also easier to shape the sides then inside fillet weld the pieces together. I also welded 2 square sections into the inside of the box section for added strength.

A local machine shop turned up the steel bush ($40.00) to fit in the recovery ring, the bush diameter is 42mm x 38mm with a 16.5mm dia hole for the lock pin.

With the box section brace attached via a 16mm pin to the bush in the recovery ring I let the brace angle down to sit on the chassis below the recovery ring (see thumb nail pic) by doing this the box section cannot drop down as it is supported by the ring and chassis.

The Hayman WDH was then slide into the D4 hitch and with the vehicle battery disconnected the WDH was tack welded to the fabricated box section.

The whole assembly was then checked for fit and ease of attachment before finally removing from the vehicle welding, cleaning and painting.

The hitch has been tested pulling the van, it fits very easy, there is no slack or rattle when in place so overall I am happy with the end result. For the people with air suspension wishing to use the Land Rover hitch this modification without the WDH part may be able to be incorporated into some of the adjustable tongues that they use.

Cheers

Howard

[elsey]

Looks very good and strong, take out a patent and then sell your design to Land Rover.

Lou...

[Epic]

Put a patent on that!

[Sprint]

that last photo...... is that seriously all there is to the towbar on a D4?????

[Epic]

Do still use your torsion bars with this set up? I know it's not advised.

[wardh]

Do still use your torsion bars with this set up? I know it's not advised.

Yes I do use the torsion bars on a minimal tension as my D3 has the coil spring suspension. I have raised King Spring coils fitted all round with heavy duty rated rear coils.

I have a level point in the yard where I set up my vehicle and caravan. The D3 uncoupled and coupled measured at 2 points front and rear are as follows.

Rear 340mm Front 365mm D3 uncoupled (R to F ratio is Rear 25mm Hi)

300mm (-40) 385mm (+20) Van fully loaded coupled (250kg ball)

335mm (-5) 370mm (+5) WDH bars 1 link tension min setting

355mm (+15) 360mm (-5) WDH bars 2 link tension

The rear to front ratio I have shown appears to be the wrong way round. My measuring points are purely for reference to gauge how much the rear of the vehicle sinks and the front lifts when the van is connected

Sitting in the level drive way and looking at the sills the rear of my vehicle is normally 25mm higher at the rear. As you can see the minimum WDH setting I prefer when connected to the van only changes by 10mm. If I did not use the bars I would have a 60mm change in attitude. If I use the 2 links the rear ends up higher than when not attached to the van

The setting I use results in a very stable tow I have never experienced any sway or unstable behavior at all.

Van is 19' 6" off road 2.5t fully loaded with simplicity suspension.

Cheers

Howard

[CaverD3]

Very similar to the SA one which was desisigned and made in about 2005. I think theirs would have weighed more.

[gghaggis]

Very similar to the SA one which was desisigned and made in about 2005. I think theirs would have weighed more.

That was the Witters one?

Cheers,

Gordon

[CaverD3]

This one:
It will actually be lighter as they didn't use the LR hitch.

[discotwinturbo]

CarverD3, is that rated to 3.5 tonne ? I can only see two bolts holding the towball bracket to the hitch....might be my eyes.

Brett....