open vs limited slip diferentials.
I have read about differentials overheating. Is this a problem 'almost' exclusive to limited slip? My new vehicle will be used a great amount of time on steep 2 lane winding mountain roads. I woul...
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One thing I've noticed in this conversation is that there isn't any differentiation on limited slip. Seems like everyone is assuming that limited slip means a clutch-based system. Any differentiation on a clutch-based system will cause dragging and will cause some additional friction. Especially if there's lots of tight corners being driven at a higher rate of speed.
However, many vehicles now a days seem to favor the torsen style limited slip. Not as effective as a viscous clutch pack since those systems can lock both sides together in extreme cases. Torsen systems can only bias torque to a degree. For example, I believe the RAM's torsen rear end has a 2.5 bias ratio. This means that if the slipping side can still maintain traction up to 50 lb-ft, then the other side with more grip will have about 125 lb-ft worth of tractive force transferred to it. The great weakness with the torsen system though, is if you have one tire completely off the ground with no tractive force, then it can't bias any force to the other side and is about as effective as an open differential. This guy does a fantastic job of showing how the different differentials work and hopefully this clears up the discussion a little bit.
As for rear lockers, the electric units used by Ford are manufactured by GKN. Very good unit and I enjoyed it with my 2010 FX4 F-150. Worked very well on the beach.
However, many vehicles now a days seem to favor the torsen style limited slip. Not as effective as a viscous clutch pack since those systems can lock both sides together in extreme cases. Torsen systems can only bias torque to a degree. For example, I believe the RAM's torsen rear end has a 2.5 bias ratio. This means that if the slipping side can still maintain traction up to 50 lb-ft, then the other side with more grip will have about 125 lb-ft worth of tractive force transferred to it. The great weakness with the torsen system though, is if you have one tire completely off the ground with no tractive force, then it can't bias any force to the other side and is about as effective as an open differential. This guy does a fantastic job of showing how the different differentials work and hopefully this clears up the discussion a little bit.
As for rear lockers, the electric units used by Ford are manufactured by GKN. Very good unit and I enjoyed it with my 2010 FX4 F-150. Worked very well on the beach.
