Tow ball tongue replacement - slightly longer tongue - is it an issue?

[Ghost-Who-Walks]

Hi Brains-trust

I have the standard landrover towbar receiver (with the keyed lock) on my D4. I've never had any problems with it, towing my camper over many rough roads.

I've just bought a new tongue (standard Hayman Reese tongue), rated to 3.5T. When I went to put it in, it's too long and hits the spare tyre under the car.
No problems there - I'll just cut the extra length off the back, so it clears the spare.

My query is around the hole location for the pin to secure the tongue - when it's in place (pin holes lined up) there is about 1-2cm of extra length protruding out the back of the car, towards the towball (ie distance between the tow ball and the pin hole through the tongue is 1-2cm longer).
In my mind, this means the ball is 1-2cm further back, and therefore there is greater load (moment) on the towbar receiver and the car overall.

Question - is this 'extra load' a problem? Or is the distance (1-2cm) going to be negligible?

Maybe I'm being paranoid, but want to make sure I don't break anything or end up stuck somewhere!

Thanks.

Rob

[kelvo]

As long as it is within the specifications in the owners handbook you’re all good.

https://www.aulro.com/afvb/attachments/l319-discovery-3-and-4-a/156175d1575878235-beegees-my15-disco-4-xxv-build-thread-fea0a1a1-272a-418a-b684-a778e588f76c.jpg

[Aussie Jeepster]

I seem to recall reading somewhere that you can't modify a tow tongue from original spec - no cutting, no grinding, no nothing.
Happy to be proven wrong, and I don't remember where I saw it, but as I remember, it came from what appeared to be a reputable source, and it was when I was sorting out the towing setup for my number 5 army trailer on my D3.

[Don 130]

There must be a bit of lee-way. The tray my 130 extends far enough that the Hayman Reece tow-bar ends with the ball under the tray. I can cope with it, but I asked H/R if it could be extended. Their answer was that it could be done but only an extra 200mm as any further would technically overload the back axle. Think you're probably safe.
Give them a ring, one of their engineers will answer your question.
Don.

[Tombie]

There must be a bit of lee-way. The tray my 130 extends far enough that the Hayman Reece tow-bar ends with the ball under the tray. I can cope with it, but I asked H/R if it could be extended. Their answer was that it could be done but only an extra 200mm as any further would technically overload the back axle. Think you're probably safe.
Give them a ring, one of their engineers will answer your question.
Don.

There is Don

The handbook gives you that leeway clearly.

200mm is a significant increase in leverage- quite significant.

[rambada]

Are there any aftermarket tongues with 152mm drawbar length? ARK do a 160mm but I can't locate a shorter one. Do I need to go original?

[Ghost-Who-Walks]

Are there any aftermarket tongues with 152mm drawbar length? ARK do a 160mm but I can't locate a shorter one. Do I need to go original?

Well, that's really interestng. The original drawbar is 162mm in length (pin hole to ball centre), as per the max. dimensions specified.
So anything longer is non-compliant. [bighmmm]

My standard, 3.5T rated Hayman Reese drawbar that i just bought is ~215mm from pin hole to ball centre - well outside the max allowable!!!
Basically the only option is the original LR drawbar (unless there's another 'short' drawbar available out there)! [bawl]

Begs the next question - can I drill a new hole for the pin in my H-R drawbar?
I'm assuming 'NO', as there's likely a minimum distance that would be needed between the 2 holes (existing + new) to ensure the new hole doesn't weaken the drawbar...

So, I have to buy another LR drawbar, me thinks!!!!

[Tins]

In Victoria we have these creatures known a VASS engineers, basically automotive engineers accredited with VicRoads to authorise modifications such as GVM upgrades etc. I assume that WA has a similar system. Given the legal ramifications I would do nothing without consulting one.

[josh.huber]

Surely it all depends on the weight being added..

I have a super long draw bar that I use just for the bike rack. Helps it clear the tail gate.. the longer the bar the more weight on the rear axle.. But if your talking a 1t trailer with 100kg ball weight. The extra length shouldn't cause concern aslong as it doesn't allow the trailer to over load the axle.. if you were close to the 250 kg mark and started making it longer then more thinking is required.

That spec says "recommended" I read it as if you go over this you'll need to re-check your ball weights effect on the car.

[josh.huber]

And no. Don't drill holes in it.

[josh.huber]

And no. Don't drill holes in it.

[Ghost-Who-Walks]

And no. Don't drill holes in it.

Thansk for the info. It was mostly a rhetorical question...

And I've already come to the same conclusion! The main reason for a 2nd drawbar was to avoid swapping between my camper hitch fitting (O'Brien coupling) and the ball for my box trailer. [bigsmile1]
Camper = large, heavy loads (weight plus shock loads on rough roads)
Box trailer = much smaller loads (green waste to the tip)

So, I think I'll use my new H-R bar with the ball fitted for my box trailer, and keep the camper trailer coupling on the original LR drawbar.
Didn't think it was going to be this complicated - but I guess it's not. But I know a lot more about my hitch/drawbar than I did before!

Thanks for the input, team! [bigsmile]

[Tombie]

Surely it all depends on the weight being added..

I have a super long draw bar that I use just for the bike rack. Helps it clear the tail gate.. the longer the bar the more weight on the rear axle.. But if your talking a 1t trailer with 100kg ball weight. The extra length shouldn't cause concern aslong as it doesn't allow the trailer to over load the axle.. if you were close to the 250 kg mark and started making it longer then more thinking is required.

That spec says "recommended" I read it as if you go over this you'll need to re-check your ball weights effect on the car.

The longer the bar, the more leverage at its mounting point. Which with the removable hitch could easily overload and damage the housing.

Not just at the axle.

[josh.huber]

The longer the bar, the more leverage at its mounting point. Which with the removable hitch could easily overload and damage the housing.

Not just at the axle.

Yeah but it's acting on the same parts of the housing as before.
So it comes back to the weight you apply to it.
I know it's not the point, but I would back the housing to outlast my replacement Hayman Reece insert. It looks like it's made from sheet metal. It's 3.5t rated bit I wouldn't put any more then a 750kg box trailer on it.

And wouldn't a Mitch hitch hang out more then a std bar?

[Tombie]

Mitch hitch doesn’t load the removable hitch mount in the rear frame in the same fashion.

I’m talking about the clip in receiver, not the tongue.

That slot in the chassis is the place I wouldn’t want strong leverage on.