Posi-traction
HLandin
04-29-2006, 08:16 PM
I know that posi rear ends help acceleration by preventing what has been termed the "one-wheel peel." And I understand how it works, using clutches to fight or help prevent one wheel from spinning faster than the other unlike open rear ends. My question is:
Since the two rear wheels are supposed to spin at different rates during a turn and a limited-slip/posi rear end fights the tendency for them to spin at different rates, do limited-slip/posi rear ends wear out faster than open rear ends due to turns?
Any input on this would be greatly appreciated.
Since the two rear wheels are supposed to spin at different rates during a turn and a limited-slip/posi rear end fights the tendency for them to spin at different rates, do limited-slip/posi rear ends wear out faster than open rear ends due to turns?
Any input on this would be greatly appreciated.
Blue Bowtie
04-29-2006, 09:14 PM
There are several types of limited-slip differentials. The common, old type used cone clutches and bellville springs or plates and springs to minimize the differential between the two axles, but allowed some slippage on turns, and also allow a "softer" locking action of the axles on dry pavement under heavy acceleration. Most of this type used an EP friction modifier in the gear oil to promote longer life of the bronze cones by allowing slippage without excessive wear. Centrifugal locking units allow full slippage between the two axles, just like a standard, open differential, until the differential reached a point that would force engagement of a set of centrifugal pawls. These pawls would lock the axles together until the speeds and forces were the same, at which time springs would return them to the disengaged position. This type works best off road, where the harsh engagement of the "loose" axle would be cushioned by some slippage on soft ground, mufd, snow, etcetera. Spinning up the RPMs and dumping the clutch on dry pavement with one of these units is a good way to grenade the rear axle.
https://www.expeditionexchange.com/tractech/DSC01943.jpg
Worm/helical geared units have helical interlocking worm gears which start to "climb" each other under load until they lock the axles together. These are also a bit more cushioned engagement than the centrifugal "lockers" and are a very ingenious design. Zexel-Torsen made these popular in the late 1980s under various performance vehicles.
http://72.19.213.157/files/ZexelTorsen-T2.jpg
https://www.expeditionexchange.com/tractech/DSC01943.jpg
Worm/helical geared units have helical interlocking worm gears which start to "climb" each other under load until they lock the axles together. These are also a bit more cushioned engagement than the centrifugal "lockers" and are a very ingenious design. Zexel-Torsen made these popular in the late 1980s under various performance vehicles.
http://72.19.213.157/files/ZexelTorsen-T2.jpg
kahjdh
04-29-2006, 09:53 PM
wow, i didnt think there was that much to it.
HLandin
05-03-2006, 06:56 PM
I was referring to the posi-traction in the Caprice, which I thought only came with clutches.
GreyGoose006
05-04-2006, 04:13 PM
I know that posi rear ends help acceleration by preventing what has been termed the "one-wheel peel." And I understand how it works, using clutches to fight or help prevent one wheel from spinning faster than the other unlike open rear ends. My question is:
Since the two rear wheels are supposed to spin at different rates during a turn and a limited-slip/posi rear end fights the tendency for them to spin at different rates, do limited-slip/posi rear ends wear out faster than open rear ends due to turns?
differentials are meant to endure some abuse. limited slip diffs are designed to do the job they do. when the differential locks, and u are going around a corner, it is the tires that get the most wear, not the diff.
Since the two rear wheels are supposed to spin at different rates during a turn and a limited-slip/posi rear end fights the tendency for them to spin at different rates, do limited-slip/posi rear ends wear out faster than open rear ends due to turns?
differentials are meant to endure some abuse. limited slip diffs are designed to do the job they do. when the differential locks, and u are going around a corner, it is the tires that get the most wear, not the diff.
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