4 x 4 Australia - - Gear -

WHEN you en­gage a locker, it ef­fec­tively re­moves the dif­fer­en­tial gear­ing ac­tion from the diff. So now you’ve re­verted back to a solid axle be­tween the wheels, and it doesn’t mat­ter if one wheel is on terra firma and the other is 50cm in the air, both wheels will turn at the same rate.

To ex­plain how a locked diff can vary the amount of torque to each wheel, we’ll have to use maths. Let me in­tro­duce you to the stan­dard fric­tion equa­tion:


F_r = is the re­sis­tive force of fric­tion µ = Fric­tion co-ef­fi­cient for the tyre against the terrain you’re trav­el­ling across. N = Nor­mal force (in Newton-me­tres), which is the weight of the car push­ing the tyre down on the terrain.

Let’s look at a sce­nario where one tyre is on mud and the other is on a road sur­face. Both of the tyres are ex­ert­ing a force of 1000N.

Adding both to­gether you get a to­tal re­sis­tive force of fric­tion 1300N, which means 77 per cent of the torque is de­liv­ered by the road-side tyre and 23 per cent by the mud-side tyre. Road µ = 1 Mud µ = 0.3 Mud F_r=µn F_r=0.3 x 1000 F_r=300 Road F_r=µn F_r=1 x 1000 F_r=1000

A locked front diff will send drive to both front wheels in this sit­u­a­tion.

TJ Jeep Wran­gler get­ting a Har­rop Ea­ton Elocker.

Newspapers in English

Newspapers from Australia

© PressReader. All rights reserved.