This 1961 Doe Triple-D (pictured above) – otherwise known as a ‘tandem tractor’ – is up for auction, where it’s expected to make £60,000-£70,000 (€68,000-€79,000).

It’s part of tractor enthusiast Paul Cable’s 38-strong collection; all 38 tractors will soon be sold (as individual lots) to the highest bidder.

All of the tractors in the collection are Ford or Ford-derived models – of some description.

Also Read: Video: Meet the man who is selling 38 Ford and Ford-derived ‘classics’

This Triple-D’s serial number is 161. The front engine’s number is 1585153; the rear engine’s number is 3038721.

What is a Triple-D?

The ‘tandem tractor’ developed by Ernest Doe & Sons of Ulting in Essex (England) is probably the most famous of all the Fordson conversions. The design, which was the brainchild of local farmer, George Pryor, first appeared as the Doe Dual Power in 1958.

The concept entailed linking and articulating two Fordson Power Major tractors via a turntable, with steering achieved by pairs of hydraulic rams.

Following improvements, the machine was re-launched a year later as the Doe Dual Drive or ‘Triple-D’ for short. The adoption of Super Major skid-units in 1960 coincided with a further revamp to improve the layout and synchronisation of the controls.

Although it appeared ungainly, the Doe Triple-D was regarded as a very potent machine; the two engines combined to deliver more than 100hp.

Shipments were made to Europe, Scandinavia, Israel, North and South America, Africa and even Russia.

One of the first Triple-Ds to enter preservation, this machine has had a succession of illustrious former owners, including John Moffitt (Hunday Collection), Tom Lowther (who restored the tractor in the 1980s), Stuart Gibbard and Bill Woods.

No shortage of muscle: The Doe Triple-D (right) pictured with a much newer Ford TW-25 (from the same collection)

While in Stuart’s ownership, it became the inspiration for his book – Ford Tractor Conversions – in which it features. Finished in Doe’s own colour scheme, the tractor was supplied new by Ernest Doe & Sons to a farmer in Essex on February 27, 1961.

The front radiator guard is believed to have been fitted from new. The Doe was purchased by Paul Cable in 1990 and is fitted with a rear linkage and a swinging drawbar.

It’s shod on 13.6/12-38 wheels and tyres. It’s described as “running and driving well”.