Retrofitting an old slurry tanker with a trailing shoe spreading system can prove quite difficult and expensive - for a variety of reasons.

Farmers who own a slurry tanker may be considering retrofitting their tanker with a trailing shoe system, amidst fears that a ban could be introduced on splash-plate spreading systems.

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For Ireland to meet its ammonia emissions targets by 2030, Teagasc believes that 50% of the slurry spread in the country will have to applied using trailing shoe systems.

Ammonia emissions would be reduced by 5.1%, compared to levels witnessed in 2005, if the utilisation of trailing shoes reached the above levels, Teagasc added.

It outlined that the move towards trailing shoes would cost in the region of €35.6 million every year, in its submission to the Department of Communications, Climate Action and Environment (DCCAE) on the National Clean Air Strategy.


This would not include the associated labour costs to implement these measures, nor the cost of education and advisory services, according to Teagasc.


Retrofitting an existing tanker with a trailing shoe spreading system is not straight-forward, according to Agquip's James O'Kane.

Based in Ballymoney in Co. Antrim, Agquip specialises in retrofitting tankers with either trailing shoe or dribble bar systems; it also manufactures tanker mounting systems.

"It's not straight-forward at all [to retrofit a trailing shoe system]. If the tanker was not initially designed to be equipped with a trailing shoe, then the balance will be all off.

If you attach a trailing shoe system to a slurry tanker on which the axle is too far forward, then there will be very little weight on the drawbar.

"You can run into other issues due to the extra weight of the new system, as well as the additional tail-swing. It all boils down to the position of the axle," O'Kane said.

In the past, Agquip has retrofitted a range of tankers – as small as 1,300-gallon units – with trailing shoes, he added.

O'Kane explained that attaching a dribble bar system would prove much more straight-forward; it wouldn't be as heavy as a trailing shoe.

Costs involved

It would cost a farmer or contractor between €14,000 and €15,000 plus VAT to retrofit a good-quality trailing shoe system onto an older tanker, O'Kane said.

The cost of retrofitting the new system does not vary hugely with the size of the tanker; but it makes the process simpler if the tanker has already been fitted with brackets to accommodate a trailing shoe, he added.

Some farmers choose to purchase the tanker with the brackets already attached. It costs a few hundred more at the time, but it leaves the option open down the line.

"With the grants available now, a lot of farmers are choosing to sell their old tanker and buy a new combined unit," he said.

In Northern Ireland, a trailing shoe system must be chassis-mounted to qualify for grant aid, he said.

Can older tanks be retrofitted?

Hi-Spec Engineering has been fitting trailing shoe systems to its tankers for about 11 years, according to the company's Jim Nolan.

A farmer or contractor could retrofit a Hi-Spec tanker from as far back as 2006 or 2007 with a trailing shoe system, Nolan said.

"The older tankers, without trailing shoe brackets fitted, will have an axle position that is approximately 7in further forward than the newer tankers that have brackets fitted.


"Fitting a trailing shoe system on a tanker with an axle that far forward would cause problems with balance and weight distribution; the drawbar may then have to be weighed down.

"Any of the tankers fitted with trailing shoe brackets will have the axle in the correct position, so that a trailing shoe can be added at a later date," Nolan said.

Nolan would not recommend retrofitting a trailing shoe system to a tanker that is smaller than 2,000 gallons.

The wheels, axle and chassis of a tanker smaller than 2,000 gallons wouldn't be suitable for the additional weight of a typical, 7.5m-wide trailing shoe, he said.

To retrofit a trailing shoe system to a 2,000-gallon tanker would cost in the region of €16,800 plus VAT, according to Nolan.

If a farmer or contractor wished to purchase a new, well-equipped 2,000-gallon tanker, fitted with a compatible trailing shoe system, it would cost in the region of €29,000 plus VAT, Nolan concluded.