World’s rarest tractors gather at Henty field days for reunion

It’s been four decades since the town of Corowa punched above its weight when it came to manufacturing the world’s biggest two wheel drive tractors.

Upton Engineering was built on the collection of ex-disposals army vehicles, tanks and spares to convert into bulldozers for scrub clearing, but ultimately produced one of Australia’s most famous tractors.

In 2023 the Henty Machinery Field Days is hosting a one-off gathering of Upton tractors – now considered amongst the rarest in the world.

Just eight Upton MT-855s were built as designer Carl Upton worked on each individual tractor himself with the help of staff, making them to order.

Upton tractor collectors will be bringing their machines from Corowa, Albury, Ardlethan, Swan Hill Mudgee and Dookie. The display has been generously sponsored by the Australia-wide Refuelling Solutions.

Field day visitors will be able to see the first tractor, Heavy Harry, built in the early 1960s by business founder Arthur Upton using a Japanese UD diesel engine and tank transmission and final drive.

Heavy Harry is now owned by Steve Pleming, Edge Machining, Dookie, Vic. It was first publicly demonstrated at Urana in 1967.

Mudgee collector Robert Allen has three Upton tractors in the family is bringing a MT-855 to Henty, while other MT-855s will come from Andrew Taylor, Ardlethan and Allan Arthur, Albury and Upton 180s will come from Bill Petzke, Corowa, and Doug Carroll, Swan Hill. 

Robert Allen’s tractor was manufactured in 1976, was the first model to have a V8 Scania engine and originally sold to Western Australia. He purchased the tractor in 2020 and fully restored it. 

“Our family farm was at Boorhaman, and was sold to move to Mudgee. At the clearing sale, Dad was left with a Minneapolis Moline tractor with a kerosene engine. He took it to Corowa had a UD engine fitted by Upton’s.

“I was impressed by the Upton’s yard full of army machinery.” Robert went on to collect three Upton tractors and says it’s a bit like fishing with “the excitement in the finding”.

Andrew Taylor’s family links with Upton Engineering go back to the 1960s when his father Lawrence built a tractor using army surplus parts from the firm. Andrew will be driving the tractor from Ardlethan to Henty via the back roads. 

Bill Petzke’s Upton 180 tractor was used for many years pulling scrub and stumps in the Mallee at Pinnaroo, SA, and remains in original working condition.

“I live in Corowa and wanted a bit of history – they were the biggest two-wheel drive tractor in the world,” Mr Petzke said.

He purchased the tractor from the Muirhead family at Pinnaroo about five years ago after it had been bought by the Muirhead’s from a dealer in Mildura. 

Still bearing its original mushroom pink paintwork, the 180hp tractor has a Nissan UD43 4.9L 4-cylinder engine and 21 speed transmission.

Carl Upton will have a display of memorabilia and history of his involvement with the design and build of the tractor. 

Corowa engineer Daryl Leahy built Heavy Harry with a 671 Series GM but switched to UD diesel engines after a visit to Japan by Arthur Upton.

“We originally built the tractor as a demonstration vehicle for the engine,” he said.

“At the time the biggest, most powerful rubber tyred tractor in Australia was made by John Deere and Allis Chalmers at around 110hp.

“Everyone needed a bit more horsepower so they could double up on the tillage machinery behind.

“The 180hp made that possible. The idea of Heavy Harry was to demonstrate the engine for repowering existing tractors, trucks and buses.”

Mr Leahy said the distinctive mushroom pink colour scheme of the early units was designed to differentiate away from other brands in red and green.

The Model 225 Upton tractor was offered in 1969 with a UD 225hp supercharged engine, and rubber torsion block front axle suspension.

The first of the MT-Series was built in 1976 and fitted with a Hercules six cylinder 200HP engine but a few months later was repowered with a Cummins NTC-290.

Still a two-wheel drive tractor, the MT sold for $48,000 in 1976 – the following year at the Henty Machinery Field Days it sported a V8 Scania 300hp engine. 

The two-wheel drive tractor matched the performance of a 310hp 4WD Steiger Panther at Henty.

Carl’s vision of building the world’s biggest two wheel drive tractors unfolded with the MT Series. The MT Series were custom built machines designed to take any 200 to 300 hp engine – Scania, Cummins, GM, Mercedes or Caterpillar.

Fitted with a 200-gallon tank, the tractor could work day and night between fills. The fuel tank weighed 1.5 tonnes empty and was built of 5/8 inch thick steel plate.

The mighty HT 14/350 was launched in 1978 as the world’s largest two wheel drive tractor – the biggest yet designed by Carl and with a 350hp engine, 14-speed Spicer gearbox and Eaton drive head into an Australian built final drive.

Today, the HT 14/350 is owned by a farmer at Goolwa, SA.

Carl had drawn concept plans for a 4WD tractor up to 600hp but a downturn in the rural economy and the company’s expansion into irrigation equipment resulted in tractor manufacturing cease in 1981.

Field day visitors will be able to see the Upton tractor display on the machinery demonstration area next to the agronomy plots.