Transmission windup, aka transmission bind. Understand it before you break something.

Your 4X4 has two axles, front and rear. When you turn a corner the front axle travels further, and therefore faster than the rear. It doesn’t matter whether you turn left or right, same thing happens.

If there’s no way for the driveline to let the front axle turn at a different speed to the rear then stress builds up and that is known as windup, or bind. This will damage and even break transmission components.

Windup isn’t a problem on low-traction surfaces like dirt as the front and rear axles can skid relative to each other and equalise speed. It is a problem on high-traction surfaces like bitumen, even wet bitumen.

The driver should hopefully notice – the vehicle won’t want to turn corners, there will be vibration and squealing noises from the tyres, all of which get worse. The cause is generally driving a vehicle that has a manually lockable centre diff on high traction surfaces with the centre diff locked, or again only on high-traction surfaces, a part-time 4WD in 4WD instead of 2WD. Many 4×4 owners have automated centre diffs so need not worry, for example any modern Land Rover.

Here are some windup myths, and everything is explained and proven in the video:

1.You need to drive quite a long way before you get windup

No, you can get windup even by driving a few metres. Just go full lock and turn on a high-traction surface. Presto, windup!

2. You need to unlock your hubs before you drive on bitumen

No you don’t, you just need to take your part-time 4WD out of 4WD. Then the front and rear axles can spin at different rates, so no windup. Locking hubs slightly reduced fuel consumption.

3. Wet bitumen won’t give you windup.

Yes it will, it’s more than high traction enough.

4. Reversing straight back fixes windup

No, it won’t. Windup is caused by the front axle rotating faster than the rear. So reversing straight back does nothing for windup. However…if there’s very little windup then you may be able to jiggle the transfer case loose enough to get the vehicle out of 4WD by reversing.

5. Turning left cancels turning right

No, windup increases whether you turn left or right.

6. You can’t get windup with open axle diffs

Yes you can. Windup is about relative speeds of front and rear axles, not different speeds between wheels on an axle.

7. The best way to get rid of windup is…watch the video! (no it’s not jacking a wheel up)