With increased payload and optimum versatility, the 8x4 chassis configuration for concrete agitators is undergoing a resurgence of interest. Pete Armstrong spends a day with a Kenworth T350 Agitator
One sector of the trucking industry undergoing a period of change is the cartage and delivery of pre-mixed concrete.
Don’t for one minute think this form of transport is a particular niche market with little in the way of competition. It is highly contested by concrete companies and truck manufacturers alike.
For many years the leader has been Iveco, the venerable Acco holding a sizeable portion of the truck market in both 6×4 and 8×4 variants. Competition, however, has hotted up particularly in the eight-wheeler segment.
Mack has realised the potential of 8×4 trucks in concrete fleets, and Kenworth is following close behind. Now the guns are out as the two make a march on sales figures enjoyed by the Acco for so many years.
It would be true to say Mack pipped the KW brand in the bid for business in concrete cartage; the development of its specific 6×4 and 8×4 chasses reaching the market ahead of Kenworth. But brand allegiance and new business dictates sales volumes.
Enter Kenworth’s T350 Agitator spec.
Released to the market at the Queensland Truck and Machinery Show in May of last year, the model has enjoyed considerable success across the country.
Initially available as a 6×4 with the eight-wheeler following not far behind, the T350 Agitator has made inroads into a number of fleets and certainly found favour with contractors.
There has been some controversy around subbies putting 8×4 mixers to work in some plants, however the benefits to companies are patently obvious.
Increased capacity and payload is vital across the pre-mixed concrete industry, particularly as large commercial projects come on line, and any increase in supply of concrete is welcomed by the building industry.
Contractors number highly in many delivery fleets. One of those is Readymix, where two subbies looking to increase payload made the decision to order the Kenworth 8×4 offering.
Bob Hinch and Ray Harris are long term contractors to Readymix and when the time arrived to update equipment they were conscious of the benefits of operating twin-steer trucks on the task.
The fact they chose the KW brand emanated from experience. Ray Harris was one of the first to take delivery of a 6×4 version and has been a Kenworth operator for some time.
Bob Hinch is an ex-long distance driver, at one time driving a K100 for Ward’s Overnighters on its Brisbane to Sydney shuttle run.
The two trucks ordered by the pair are identical apart from minor optional extras.
Since they went into service a few months back the operators report complete satisfaction with the units, citing power, ride, handling, comfort and manoeuvrability as particularly impressive.
“One thing we wanted and got was the new Cummins ISC engine with common rail injection,” Hinch says. “Latest technology in power and driveline specifications is worthwhile in terms of reliability and cost efficiency.
“The technology march in trucks is returning a host of benefits to operators and we wanted to have the latest available.”
The two vehicles are powered through the rear axles with a ratio of 5.29:1. Both ride on Kenworth’s Airglide 400 air suspension, with Alcoa alloy rims and shod with 11R tyres.
The spec, according to Hinch, is ideal for his agitator application as it provides excellent gearing.
Additionally, with full crosslocks, all types of terrain can be negotiated, particularly in tough going where traction is a problem.
The Hinch truck offers a payload of 7.4 cubic metres under Mass Management, a considerable increase over his previous truck.
The 8×4 configuration offers excellent manoeuvrability in the tight spots agitator trucks need to negotiate on a daily basis.
Engine and Transmission
The two vehicles feature a Cummins ISC engine rated at 285 horsepower. The Kenworth T350 Agitators both utilise Eaton’s nine-speed transmission.
Cab and Controls
The first thing to impress was the quietness within the cab environment — low noise levels are important to any operator in terms of beating fatigue.
Low noise combined with easy shift movements in the transmission and light handling means the truck is an ideal unit for metropolitan work. This is one thing Hinch is much in favour of.
“It is a very quiet truck and easy to handle, and that removes effort from a day’s work,” he comments. “You need a truck that moves easily through the traffic and is able to maintain road speed.”
But if ability to handle on-road duties is a priority, then the work agitators do off the bitumen and across tough building sites is even more important, particularly when it comes to traction.
Performance
Loading at the Readymix plant at Albion in Brisbane, Hinch emerges from the batching plant with a full load destined for a school building project located in the suburb of Taringa, a hilly location with narrow streets.
Moving into the Saturday morning traffic the Kenworth performed well through its gear changes, bringing the vehicle up to the speed limit quickly, matching traffic movements.
On arrival at the unload point it was easy to see these vehicles are subject to some pretty tough working conditions.
The 8×4 was required to back onto a concrete pumper down a very steep incline, traversing a soft earth track approximately 80 metres long — not so bad going down but a nightmare coming out.
The 8×4 configuration offers surprisingly good manoeuvrability and, in this instance, the truck had a narrow path to the pumper unit, requiring a hard turn to the left in reverse with little clearance on both sides of the vehicle.
Some trucks require two hits at the turn, wrestling the steering wheel, but the Kenworth was in with one fluid movement.
Standard equipment on the truck is a park brake alarm, sounding loudly if the brake is not applied before the door is opened.
Hinch demonstrated the feature as he opened the door of the vehicle after coming to a halt without applying the maxis.
He hopped down from the driver’s seat, going to the rear of the vehicle where he began the discharge process using his remote control keypad.
Agitator operators need to be highly skilled when it comes to product flow, precisely measuring and monitoring the concrete to match requirements of both pumper and layers working some distance away.
The barrel was emptied in around 20 minutes and then it was time to climb the incline from the unload point.
With engagement of the cross-locks an audible warning sounds and the truck slowly made its way to the top with no falter from the drive wheels.
The rutted surface subjected the chassis to some tough treatment, but the Kenworth is built with 270mm chassis rails for durability to combat this type of terrain.
Visibility is another all-important aspect in agitator operation and the T350 has a large windscreen offering a good view over the sloping bonnet.
Hinch says he was going to order a peeper window in the passenger door but the Kenworth came standard with the fitment.
“We work in some very confined areas and every bit of vision is vitally important.
“The peeper window and the daylight doors are very good for the application, particularly with a bonneted truck,” he remarks.
Two simple clips hold the bonnet in place and when raised there is a huge amount of access to all areas of the engine, importantly those items requiring daily checks and required service points such as filters, injector pump and fuel lines.
Tare weight is what transport is all about and the agitator tips the scales at an impressive 10.3 tonnes.
Operating under the Mass Management Scheme, embraced by most Readymix subcontractors, legal load equates to 7.4 cubic metres of pre-mixed concrete.
“This is dictated by the mix, and it is possible to load the 7.4 metres on the north side of Brisbane while on the south side it is 7.6 metres, all due to the density of the stone used in the mix,” Hinch explains.
“Density of stone from various quarries differs and that has an impact on the weight of the product.
“Readymix will not overload any truck under any circumstance and each load volume and weight is carefully calculated right down to the last kilogram, so weight is never a problem.”
Verdict
Walking around the truck, Hinch says the decision to buy the Kenworth was based on experience with the product, adding the build was very much to his liking.
“I think the Kenworth is better put together than most on the market. This leads to increased reliability where it counts.
“One thing I do like is a refinement like silicone hoses, because on the truck I traded I was forever replacing hoses and this should put an end to that,” he grins.
In fact Bob Hinch is very happy with the Kenworth T350 Agitator 8×4 package, citing performance, comfort and ease of operation as obvious benefits.
“I was looking for a truck that would do the job efficiently with a high degree of reliability, and this is a unit I will have for a number of years.
“When I first went to see Bruce Barnes at Brown and Hurley about the truck I had definite ideas about the spec and optional equipment I wanted, but most of those options came as standard equipment.
“One thing I was seeking was air suspension under the cab, but the drive required for the bowl meant there was no room.
“However, the ride is excellent and I found no need for the fitment after all,” Hinch says.
“The truck does everything I ask of it and is very well suited to the application, so it’s been a good move.”