how does the diff lock work?

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AlexB
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how does the diff lock work?

Post by AlexB »

Afternoon all.
Alex from Holmfirth (west yorkshire). Just aquired a super dexta (Must not forget the "New Performance" bit I suppose !).
After owning some T20s and replacing them with a 990, I gave up on tractors for several years and became immersed in Land ROvers, before buying this 1963 model

My question is how does the diff lock work ?
Is it an actual lock or like the Fergies, where the lever just brakes the wheel ?
(My owners manuals / handbooks are in the post)

Added bonus question is which of the two lights in the dash is oil and which is generator ?

Many thanks

mathias1
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Re: how does the diff lock work?

Post by mathias1 »

the diff lock is really a lock. it connect's the right and left wheel. It's not related to the brakes. Use it the right way: It should be engaged before the wheel starts spinning, otherwise you risk to break something inside. You need to brake or declutch to disgage, otherwise the tractor won't turn.
Fordson Super Major New Performance
County Super 4 built on the Fordson Super Major
Selene built on the Fordson Super Major New Performance with Silvant winch

AlexB
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Re: how does the diff lock work?

Post by AlexB »

Many thanks Mathias

Jerry Coles
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Re: how does the diff lock work?

Post by Jerry Coles »

The differential in the rear axle allows the driven wheels to turn at a different speed when turning (the inner wheel will turn slower than the outer wheel). This is all well and good for the majority of driving whether on the road or in a field. The purpose of the difflock is to stop the differential turning when trying to compensate for different rotation speeds of the wheels. The difflock is used when you find yourself in a situation where one wheel has lost it's grip and is spinning and therefore absorbing all the engine power but your getting nowhere as the other wheel is stationary ie no forward movement as it's not being driven. The difflock effectively allows power to go to both wheels equally and so even if one wheel has lost it's grip the other wheel will drive and get you moving again. Once your free then release the difflock otherwise you may experience excessive tyre wear due to scrubbing of the wheels as they go around a bend. Known to snap halfshafts if kept locked.
The Army had six wheel vehicles such as the Stalwart, Saladin and Saracen that you had to "bounce" the wheel off a kerb due to lock up of the differentials on the road (cross country the continuous momentary disconnection of a wheel with the uneven ground too care of this).
IMHO
Jerry
Jerry Coles
Camerton, Bath, UK
West Highland White Terriers, Dexta's, E27N's and DUKW's

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