IFJ retrofitting 7.5m dribble bar on 15-year old 2400LGP

Peter Thomas Keaveney of the Irish Farmers Journal travelled west to our factory in Co Mayo to follow a 15-year old 2,400 gallon LGP tanker through a retro-fit process where it was married up to a new MAJOR 7.5m 32 outlet dribble bar slurry spreader.

With the days of the traditional splash plate numbered, many farmers are availing of grant-aided support through the Targeted Agricultural Modernisation Scheme (TAMS) to make the move to Low Emission Slurry Spreading (LESS) technology. All farms in derogation are now required to apply slurry through a LESS method.

Under TAMS, farmers can avail of grants on LESS technology such as dribble bars, trailing shoes or disc injection systems with or without a tanker.

Often, it will make more sense to take the plunge and go new, but this will be up to the farmer in question. For those interested in finding out what’s involved in retro-fitting a dribble bar to an existing slurry tanker, we travelled to Major to follow a 15-year-old 2,400-gallon tanker through the process.

Inspection and cleaning

Before bringing the tanker to a dealership or initiating the retro-fitting process yourself, it’s important to run a few loads of water through the tanker. Bear in mind you will have to take off the back door, so the tank should be fully emptied.

Once clean inside, the outside should be power-washed down. This is important as it allows you take a good look at the steel, especially around the back door, to ensure it’s in suitable order to carry a dribble bar.

Remove couplings

All tanks will either have one or two rear quick-attach couplings. These will have to be removed and blankers fitted instead.

If in good order and functioning correctly, the same quick-attach couplings will be fitted at the rear of the dribble bar as seen in the pictures.

In a similar fashion, the gate valve and splash plate needs to be removed and can also be used once again.


The dribble bar will slot on to the rear door. Unless the existing hook bolts are in very good order, new nuts and bolts should be used and tightened accordingly.

Different tankers may have varying points to attach the two supporting braces. On the newer major tankers, brackets are welded to the rear bevelled door.

However, on the older tankers Major braces two reinforced pieces of flat steel on to the light brackets. This is just a matter of bolting one brace from the brackets on the dribble bar frame to the lighting brackets.

The reinforced braces are supplied with the new dribble bar. They offer increased support and stability.


First up is to remove the existing hydraulic hose, which runs from the gate valve to the tractor. It’s no longer necessary.

Before slotting through the new hoses, the existing hydraulic brake hose should be checked for damage/corrosion.

In the tanker, we followed through the retro-fit, this needed replacing. As regards hydraulic hoses to match the new dribble bar, most manufacturers will supply a full set cut to length.

As there will be an increased number of hoses required, Major fits a tidy hose holder at the front of the tank.

The hoses should be neatly slotted back from the front to the rear, one by one. Most tankers will have a channel along the chassis for the hydraulic hoses to neatly fit into.

Corresponding hoses should be marked with paint to make the matching up process easier. Once these hoses are brought to the rear, they can be married up to the valve block on the dribble bar. Major uses a 5/8 hose over a half-inch hose for less resistance in oil flow.


Once the dribble bar and hydraulic hoses are attached and tightened, it’s time to run the pump and check no air is being sucked in, particularly around the tanker’s back door, the gate valve and at the two rear suction points.

It’s also important to check that all the hydraulic functions are operational.

Dribble bars will typically require a minimum of three spool valves – one to run the macerator, one for the hydraulic up-and-down folding of the wings and the final to open and close the gate valve leading to the macerator or splash plate.

However, with the use of a solenoid and a diverter through the control box, the Major dribble bar requires two spool valves. The diverter switch on the control box alternates flow to the gate valve or the folding of the wings.

This control box will be located in the tractor cab and is powered via a three-pin plug connection.

Meanwhile, the dribble bar will have its own LED lights which run to a seven-pin plug. This will need to be wired into the tanker’s existing lights.

Time and cost

Fitting a typical dribble bar to a standard tanker will take in the region of four to five hours.

One person will be able to carry out most tasks, but will need the help of a second person for marrying up the dribble bar to the back door.

Different manufacturers will have varying prices and sizes of dribble bars.

The dribble bar featured was a 7.5m version manufactured by Major itself, which would be the most popular size. Major has said that if the retro-fit is straightforward, its dealers will fit and supply the 7.5m 32-outlet dribble bar to a tanker for €12,900 including VAT.

Tanker size and suitability

There is a lot of talk out there on retro-fitting LESS systems to tankers and the upsetting effects it may have on weight distribution on the tanker’s drawbar.

Major claims that this typically isn’t an issue with most dribble bars which tend to weigh 500kg to 700kg. This particular 7.5m dribble bar we fitted to the tanker featured weighed in at 630kg.

Major claims there would be no off-balancing of weight on tankers as low as 1,700 gallons with this dribble bar.

However, on a smaller tank, Major says the impact will largely be felt on the road, as when it’s fully loaded the weight won’t be entirely down on the tractor’s drawbar. This will also have an impact on traction in the field, which is very important at the shoulders of the year. It’s worth having a conversation with your manufacturer about weight distribution before making the investment.


The sump/stone trap underneath the gate valve on the dribble bar should be emptied regularly. Most dribble bars will have grease points on the hinge points which should be adhered to.

The jubilee clips that hold the hoses can break and should be checked regularly.

Once you know you are finished using the system for a period of time, a load of water should be run through it.

Ideally, it should be stored folded down in the working position and indoors. Frost and direct sunlight are hard on the hoses and can lead to cracking, especially if stored folded up.


The article was originally published on 30th December 2020 in the Farmers Journal here.

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