Of the many great technological leaps made in the middle of the 20th century, one of the ones with perhaps the greatest impact on our modern life takes a back seat behind the more glamorous worlds of electronics, aeronautics, or computing. But the ancestor of the modern tractor has arguably had more of an impact on the human condition in 2025 than that of the modern computer, and if you’d been down on the farm in the 1940s you might have seen one.
The Ferguson system refers to the three-point implement linkage you’ll find on all modern tractors, the brainchild of the Irish engineer Harry Ferguson. The film below the break is a marketing production for American farmers, and it features the Ford-built American version of the tractor known to Brits and Europeans as the Ferguson TE20.
As the four-wheeled machines grew in size and their implements moved beyond the size of their horse-drawn originals, they started to encounter a new set of problems which the film below demonstrates in detail. In short, a plough simply dragged by a tractor exerts a turning force on the machine, giving the front a tendency to lift and the rear a lack of traction. The farmers of the 1920s and 1930s attempted to counter this by loading their tractors with extra weights, at the expense of encumbering them and compromising their usefulness. Ferguson solved this problem by rigidly attaching the plough to the tractor through his three-point linkage while still allowing for flexibility in its height. The film demonstrates this in great detail, showing the hydraulic control and the feedback provided through a valve connected to the centre linkage spring.
A modern tractor is invariably much larger than the TE20, will have all-wheel drive, a wider-spaced three-point linkage for much larger implements, and a much more sophisticated transmission. But the principle is exactly the same, and in use it provides an identical level of utility to the original. While the TE20 is most likely to appear in over-restored-form at a tractor show in 2025 running on an odd mix of paraffin and petrol they can still sometimes be found at work, and albeit a few decades ago now I’ve even taken a turn on one myself. What struck me at the time was how small a machine it is compared to the heavyweight drawbar tractors it replaced; the effect of the three point linkage on ground pressure was such that it simply didn’t need the extra size. It’s equivalent to what we today would refer to as a yard tractor or an orchard tractor, the last one I drove being used for ground maintenance at a sports pitch. I have to admit that if I saw one in need of TLC at the right price I’d be sorely tempted.
So next time you see a tractor, take a look at its three-point linkage and think for a moment of those 1940s machines it’s derived from. It’s likely almost everything you eat has at some point been touched by that piece of machinery.
I think every operator is familiar with the three point linkage at this stage. It was found with ferguson’s method of placing the lift cylinder inside the back end that the cast iron cylinders could occasionally crack leading to a costly repair. That’s why modern tractors usually place a pair of hydraulic rams outside, which does have the downside of corrosion if the arms are left up.
I recently had a ford tractor repaired for a cracked lift cylinder as it would no longer lift silage bales.
If you like, you can write an article about fords load monitor in their 7600 tractor. This was a complicated hydraulic lift system for ploughing that automatically raises the plough if it hits a stone. I never quite figured out how to operate it.
In the midwestern US, the farmers just call it a “three point hitch”.
I’ve got one for £500.
… buyer collects.
Get thee behind me… :)
I’ve worked with a Ferguson 35, though not in cultivation. I was taught, that the key thing about the Ferguson linkage was it’s line of action… below the center of the axle it was attached to, compared to above for previous tractors. This meant the drawbar pull forced the nose down, not up. Nb drawbar pull, not implement weight. (That’ll still make a fergusons steering light enough for you to need the side brakes. ) The other big thing about Ferguson tractors was their great size and cost match to the agriculture of their day especially field and access size. As far as external vs internal arm lift rams go, an internal ram happily works at a considerable leakage rate if necessary, (with no pollution or loss of expensive oil) , is protected, and has no need of vulnerable not-quite reliable rubber hoses. (There have been revolutions in that technology just as much as in electronics) .
I doubt the nose is really forced down by the pull, since the rotary moment is between the drawbar and the wheel/ground contact point (not the center of the wheel). The lower the drawbar, the better, but for zero lift the force on the drawbar would have to be on ground level (or the drawn equipment would have to push the drawbar upwards … did it? A plow/plough easily may do that).
Umm, beg to disagree. I think you’d be right if the wheel was solidly fixed to the axle. But there’s this near-perfect bearing between the two, turns the assembly into a see saw of sorts
the bearing doesn’t do anything to the forces (the lever is not fixed to the rotating wheel, but is defined by the ground contact point, around which the drawbar force as well as the motor try to rotate the wheel), so I’m not sure we really disagree (at least for v=0)
When I tried to buy a tractor for my little acreage I was astounded by the prices. If it had a drawbar, it was cheap (unless restored) and pretty much useless for my needs. If it had a 3pth it could be an old piece of crap and still command a crazy price.
I ended up buying a new subcompact Kubota for nearly what a used one went for at auction.
This is not 100% correct. The fergusson system actually refers the how the hydraulics work in reference to the 3 point system .
In 2025, Triple 5 Farms in Tennessee runs these on a daily basis for farm operations. They run 2, to-30 fergussons , an 8n and a 9n spanning the entire of spectrum of ford built tractors.
Interesting. This may explain why the early 50s Nuffield my dad had in the early 70s didn’t have the extra hydraulics at the top.
Someone forgot about the 2N Ford tractor that replaced the 9N in 1942 and built into 1947. The 8N was built after Fergusun was forced from the partnership.
I believe Harry Ferguson was Scottish not Irish. Prove me wrong?
Born in Dromore, County Down. Very likely Scots ethnically though.
Just want to point out, it’s generally accepted that Willie Sands, Harry Ferguson’s mechanic, was the real originator of the 3 point linkage. I believe it’s a candidate for the greatest invention of all time, and definitely the greatest invention to originate on the island of Ireland.
Also, Ferguson-Brown tractors (the initial production application of the system) are little works of art, having all that is needed for viable power on the land.
“known to Brits and Europeans”
Is this what we’re doing post-Brexit? Surely we can agree Britain is still within the European continent if not the European Union?
That would be Guinness… hands down…
An article about
And not a single image/schematic/diagram about it or even a link to a wiki page…. :-/
For those with little connection to agriculture and/or English as a 2nd/Nth language that would’ve been really nice.
I’ve tried pasting a link for you twice now. It won’t work. Search for “friends of ferguson heritage “
Thanks but I’m not sure what that search terms are supposed to lead me.
I thought more of any of these pictures https://duckduckgo.com/?q=ferguson+three+point+linkage&ia=images&iax=images
Your pictures are of the outside, the game changing idea was on the inside, this site has a good overview on its technical page under the sib page hydraulics : trying again https://www.fofh.co.uk/tech/hydro.htm
Sorry, something is stopping me posting links. … The Friends…” site is a Ferguson Fandom. On their technical page there is a hydraulics page which is the best explanation of the game changing automatic implement height/depth control system. I’ve seen The pictures you link are just the outside of the thing, a major advace, but not the cropping farmers transistor, as it were
We had an old Massey-Ferguson that we restored on the farm. We had to completely redesign its electrical system, as it was a 6-volt system with a discreet generator and rectifier. There wasn’t much to it, though. Just the lights and ignition/starter. But 6-volt stuff is kind of hard to come by these days.
A tangential topic:
János Korbuly, a prominent Hungarian engineer, served as lead engineer at the Vörös Csillag (Red Star) tractor plant in Hungary. Under his direction, the factory adopted a design philosophy often referred to as the “Dutra principle” – namely positioning the engine ahead of the front axle to shift more weight onto the front wheels. This configuration generated significant adhesive force with the ground and gave rise to the so-called “nose tractors,” which proved especially effective in challenging soil and traction conditions.
Among the notable tractors designed under this principle were the UE‑28 and D4K series. The UE‑28 tractor introduced the “orrnehéz” (nose‑heavy) layout combined with four‑wheel drive, while the D4K models went further: they featured identical front and rear wheel sizes, fixed track width, and a near 50/50 weight distribution under load – all to optimize traction and pulling power.
Korbuly János and his co‑designer Rhorer Emil were awarded the Kossuth Prize in 1963 in recognition of their pioneering work on Dutra tractors and their contribution to Hungarian mechanical engineering.
Links and pictures:
https://agro-specs.com/tractors/6508-dutra-d4k-a.html
Sounds like the English “County” tractors tons on YouTube, sorry struggled copy a link
Woah, they looks lovely, thanks for the hint.
That said, I’ve checked all their models, and none seem to have that prominent nose like the Dutra 1300 : https://agro-specs.com/tractors/6505-dutra-1300.html
They made beautiful tractors: https://www.zaol.hu/helyi-eletstilus/2020/08/a-szepseges-nagyvas-dutra-ue-28-osszkerekhajtassal-minden-piacon-hoditott
Sorry report was fat finger. My understanding is that the first counties were 2 ford tractor back ends mashed together.
That’s interesting. Those designs had a big influence on machines elsewhere during the 1970s.
The Three-Point system remade the tractor marque landscape. Allis-Chalmers and John Deere initially passed on buying into it. Ford saw the potential. Everyone was forced to eat crow in the 1950s and buy in at a much higher price to survive. By the 60’s it had become standardized as we know it today. There’s quite a fascinating history as to legal battles over the hitch patents and corporate maneuvering. I still mow our horse pasture with a 1956 John Deere 40-U connected to a 2006 John Deere 503 mower- 50 years difference. That right there shows the endurance of the Three-Point.
I bought my Ford 9N in 1996 for 2100.00.
Could probably get 3500.00.
It’s a mighty workhorse.
My grandfather owned an English Ferguson and when it was rebuilt by my father who was a mechanic with a little boring he adapted Chevrolet truck pistons to the little tractor made it an awesome powerhouse compared to the other neighbor who had an American Ferguson. We done everything with that tractor mowing hay, raking, teding, pulling a trailer and a hay loader at the same time, mowing pastures, hauling manure plowing and disking it done everything on the farm. My father had it set up where if electric was out could run the milking machine off of the vacuum .
Pretty sure a few of these are still being run in New Jersey. I know one is currently a ‘lawn gnome’ on one farmers driveway but I’m pretty sure I’ve seen some working parts of a field. Farmers around here are not quick to get rid of old tractors.
So, are we not at all talking about Fergusson Formula, the genious four wheel drive system that in the Jensen FF predated all other quattro/four wheel drive systems for cars?
TE20<>9N.
A 9N is a Ford tractor with the Ferguson System. A TE20 is a Ferguson built tractor, practically nothing interchanges.
The way the plow is hooked up, it will try to pivot while pulled, forcing the top link to put pressure on the front wheels. The earlier Fordson(and other drawbar type tractors) would have a tendency to rear up, so much so that some had pendulum kill switches in them to shut them down when the front came up too high. You could now plow your field without worry a tree root or stone would kill you.
When I was a kid, some stationary equipment was run using big belts. The same system that traction engines transferred power to threshing machines etc. But at some point Power Take Offs were the preferred way: no danger of a breaking belt running amok. They were primarily used to power towed equipment like balers. When did the PTO system for tractors get standardized? According to https://en.wikipedia.org/wiki/Power_take-off it evolved.