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Parts Rear Axle


How Do Differentials Work?

A differential is the gadget that separates the torque of the engine in two ways so that each output can spin at a different speed. You can usually find this in a lot of all-wheel-drive & full four-wheel-drive cars today.

You’re probably thinking, “Well why do I need this on my car?” Technically speaking, all of the wheels on your car spin at different speeds. Let’s say you’re making a right turn at a light; the inside wheels (the ones closest to the curb) have a much less shorter distance to travel than the ones on the opposite side. See what I’m saying? The formula to calculate speed is the distance that is traveled divided by the time it takes to travel that distance. If you happen to have either Rear-Wheel-Drive or Front-Wheel-Drive, then you don’t have to worry about it. Since they spin independently, there is no connection between them.

The wheels that are driven are connected: the engine & the transmission can spin both wheels at the same time. If your car doesn’t have differentials, this would cause for the wheels that are driven to be locked together. This means the wheels would have to spin at the same time, causing you to have difficulties when you turn into driveways, corners, et cetera.

The most common differential is called the “open differential”. There’s a lot of terminology to learn, so I’m just going to try to explain it while I go on. Ready? Pretend you’re just driving straight with no where else to turn, both of your drive wheels are obviously rotating at the same speed, right? There’s something called the Input Pinion that is spinning the cage & the ring gear. This pinion is smaller than the ring gear & the cage, which means it’s the only gear reduction in your vehicle. When you’re wheel needs to make a turn, the pinion gears start moving in the cage whereas when you’re going straight, the pinions moves with the case.

Even though the wheels may be spinning at different speeds, the open differential never hesitates to apply the same amount of torque to each individual wheel. When you’re driving in dry conditions where the traction is abundant, the quantity of torque applied is restricted by the engine & gearing in the vehicle; but when you’re driving in the mountains, in the snow, or in climates like that, the torque will give just enough quantity so that your wheels won’t end up slipping. So say you’re driving on thin ice (hopefully you’re not), you’re going to want to start in either second or third gear so that the gearing in your transmission will limit the amount of torque available to your vehicles. Even when you’re going off-roading, you’re differentials may cause you some trouble. When you have a truck that’s four-wheel-drive with an open differential in the front and the back, you can get stuck. To me, it’s pretty funny; but it may not be so funny when I’m in that situation. See, when you’re going off of those cliffs & one of the back tires comes off the ground, they will keep on spinning in the air so you really won’t be able to stop…

There is something called LSD (Limited Slip Differential), or positraction, that works by giving more torque to the non-slipping wheel; that way, you’ll be perfectly fine when you go off-roading.

29/09/2011 Posted by | Uncategorized | , , , , , , | Comments Off on Parts Rear Axle


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