Model T Ford Transmission (Gearbox): How it Works + Facts

The 1908 Model T Ford was probably the most important car ever made, providing affordable mass transport for a rising American middle class and becoming the symbol of the United States’ great surge of modernization in the early 20th century.

One of the cleverest parts of the Model T Ford was its transmission, but its design and operation has long been a mystery to enthusiasts and the public alike.

Fans of the car might know that you changed gear by pressing pedals. But where was the throttle pedal? Any why were there only two gears? If you’ve ever been puzzled by the Tin Lizzie’s transmission, read on…

The least satisfactory aspect of early cars was the sliding-pinion crash gearbox (transmission), which originated from the back gearing of lathes. To change into another gear the driver had to disengage the clutch, de-select the current pair of gears and slide another pair of spinning gears into engagement with each other, with horrific grinding, screeching noises.

“C’est brutal, mais il marche” or:

“it’s brutal, but it works.”

René Panhard, speaking about his crash gearbox of 1891

And so early cars were hard to drive because of this difficulty of changing gears with the old crash gearbox. You had to learn skills such as double declutching, and have a lot of mechanical sympathy. Many new owners point blank refused to drive the car, hiring a driver, or staggered around in top gear as much as they could.

Acknowledging everyone’s dissatisfaction with the crash gearbox, Henry Ford looked around for something easier to operate.

Realising that on the Great Plains of the United States there might be no-one within a hundred miles to show you how to drive the thing, Henry Ford used an epicyclic gearbox in his previous Model A, and he would again in the Model T.

By simply pushing down a pedal the car would go forward slowly. Letting the pedal up again would make it change into high gear, going forwards faster. Pressing another pedal would make it stop. Pushing another would make it go backwards. This all seemed more natural to horse riders: Henry Ford’s first customers.

The Model T gearbox resembled the inside of a giant pocket watch. Epicyclic, or planetary gears run together in constant mesh with other gears which are attached to brake drums. These planet gears drive a sun gear called a Driven gear.

By braking or releasing the brake drums with the pedals you can make the planetary gears run on different sized gears, making them drive the Driven gear at Slow speed or Reverse. Locking the whole lot together with a clutch gives you High speed. It sounds simple, doesn’t it…

Despite Henry Ford’s claims, he hadn’t invented the epicyclic gearbox: that was the Ancient Greeks in about 500 BCE. The Antikythera Mechanism was a sort of clockwork pocket astronomical calculator which employed epicyclic gearing which imitated the Moon’s progress around the Earth. But Ford probably never knew – or cared – that what he found had been invented by the Ancient Greeks.

History is more or less bunk. It’s tradition. We don’t want tradition. We want to live in the present and the only history that is worth a tinker’s dam is the history we make today.

Henry Ford, in an interview with reporter Charles N. Wheeler for the Chicago Tribune, 1916

The British inventer and car maker Walter Wilson had used an epicyclic gearbox in his Wilson-Pilcher cars of 1901, realising that large torques could be controlled with small input forces (source wikipedia).

The epicyclic gearbox was not particularly new in the US, either, the 1901 Oldsmobile Curved Dash had a similar gearbox.

A Ford Model T open two-seater
Ford Model T from 1912

What Kind of Transmission did a Model T Ford Have?

The Model T Ford had an epicyclic transmission or gearbox. The two forward speeds of the Model T (there were only two), and the single reverse were engaged by pressing pedals that stuck out of the floor.

These applied wood or cotton-faced friction brake bands to the gear sets, locking one or other of the gears, and therefore providing a low ratio or a reverse.

How Does the Model T Ford Transmission Work?

An animation is worth a thousand words. See wikipedia.

The Model T Ford transmission works like this: the engine flywheel drives (or rotates) three planetary gears mounted on it. Each of these three planetary gears has three rings of different gears on it. The front one is meshed with (or geared to) a driven sun gear. This drives the Brake drum and also the rear wheels (see

The other two rings of gears on the planetary gears are meshed with either the Slow Speed drum’s gear, or the Reverse drum’s gear. When the clutch is engaged, the whole lot revolves together and you get High Speed.

You can select Slow Speed gear, High Speed or Reverse Gear. These are selected by the drums being locked in place by brake bands, which are clamped onto the drums by pushing the floor pedals.

These force the planetary gears to roll round either the Slow speed gear or the Reverse gear. The planetary gears then revolve the Driven gear which rotates the rear wheels and makes the car move along (see below)

You can easily adjust the brake bands by removing the floorboards and screwing the appropriate nut along its adjusting stud (source ).

Pushing the left pedal engages Slow Speed and disengages the clutch. Lifting the left pedal engages the clutch, which locks the whole gear train, which gives you High Speed.

Remember this is not an automatic transmission, it is at best semi-automatic as you still have to select the correct ratio by using the pedals. At the rear of the transmission is the Brake drum, which when clamped by the Brake band slows down or brakes the rear wheels only.

How Do You Shift Gears on a Ford Model T, Then?

When you climb into a Model T Ford you will find three pedals on the floor. These are for the clutch, brake, and gas, right?


None of these is the gas/throttle. From the left, first you find the gear pedal. Pushed and held all the way down it selects first gear. Neutral is halfway up, and all the way up is top gear. Remember the Model T only had two speeds forward and one reverse.

The middle pedal was for reverse, and the right pedal was the brake. The gas, throttle, or accelerator was a lever to the right of the steering wheel, just like a tractor. The lever to the left of the column was the spark advance/retard.

Once you get the engine running by swinging the starting handle at the front you jump behind the wheel and in your left hand grasp the brake lever which has been pulled back to safely hold the car and also put the transmission in neutral.

Place your left foot lightly on the left pedal, keeping it in neutral, your other foot on the right brake pedal to hold it stopped. Then pull down on the right-hand throttle lever on the steering column gently to increase the engine to a fast idle.

Then release the emergency brake lever on your left and press the left pedal firmly to the floor – no gentle slipping, as this will burn out the Slow Speed band. The car will now start to move forwards.

Now you can pull the throttle/gas/accelerator lever down to increase the speed. As your road speed increases you can let the left pedal all the way up. This engages the clutch and shifts the transmission to its top gear, or high gear. You then adjust the throttle lever to the road speed you want.

Now you are driving, the Model T Ford feels like a go-cart on stilts.

This all takes time to learn, but probably less time than learning to ride a horse. (source

Did the Model T Ford Have a Clutch?

The Model T Ford has a clutch, but not the single disc dry clutch found in most manual gearbox cars. It is a multi-disc clutch running in engine oil. There are no less than twenty-five clutch plates!

Today’s automatic gearboxes still have epicyclic gearsets, brake bands and multi-plate clutchs running in oil, so Henry Ford was certainly following the right lines.

A White Ford Model T Model Torpedo Roadster 1912 shows its brass fittings
Ford Model T Model Torpedo Roadster 1912

What was the Warford Transmission?

For those who found the Model T’s two speeds too limiting for hill climbing and fast road cruising there was the option of fitting an auxilliary extra transmission behind the standard transmission . The Warford Underdrive gearbox was patented in November 1911, not long after the car was introduced by Ford. It provided two gears, or ratios.

The Warford was offered to the Model T Ford owner as an auxilliary transmission for improved load hauling and hill climbing. It mounted straight on to the back of the Model T transmission, with the tailshaft cup and uni-joint fitting into the rear of the Warford. It was necessary to shorten the car’s tailshaft and rear radius rods as well, so it was a serious bit of surgery.

The idea was to order the car with the higher 3:1 ratio final drive. The car could then cruise with lower engine revs or higher road speeds than the standard low ratio differential. When a moderate hill was encountered the driver could remain in High gear and shift into the Warford Underdrive, giving a slightly lower ratio.

If a steep hill was encountered the driver could first shift into Low gear, then use the Warford Underdrive to provide an even lower ratio to defeat the steepest hill when carrying the heaviest load (source

The early manual gearbox Range Rovers had the option of a Fairey Overdrive which did much the same thing as the Warford Underdrive Gearbox but provided an overdrive instead of underdrive.

It reduced the engine revs at high speeds or enabled the old Range Rover to exceed 100 mph. I had one of these with a 6.5 litre GM diesel V8 fitted, but the monstrous torque blew the Fairey Overdrive apart, not once but twice.

Did you know…?

Henry Ford’s cost scrimping was legendary. The company manufacturing the transmission gears for Ford was given careful specifications for the wooden boxes that the gears were to be shipped in. When a manager from the company visited the Ford plant he found out why.

The workers were cutting up the empty wooden shipping crates and using them to make the floorboards in the Model T. So if your car’s floorboads are original they were once the containers that the transmission gears came in.

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