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a key point in the strength of the 9'' is the third bearing on the pinion.
this bearing does give much more support,but is actually needed because the two taper bearings are very close together.on the stock car housings,the casting around this bearing has a tendency to break,and the pinion loses all it's support.this is compounded by the pinion sitting lower on the ring gear,putting more leverage on it.
ford produced a 'nodular iron' housing that toughened up the whole shebang,but that bearing was the real benefactor.aftermarket housings are even stronger,and lead to a nearly indestructable unit.
as for user friendlyness,the 9'' is king.pull the center out and stick it on the bench.try that with an 8.8.
the pinion can be shimmed without changing any bearing settings or preload,as the whole bearing assembly comes out whole,and is shimmed at the housing as a unit.
also,shims for backlash and preload don't exist.this is set with screw in bearing adjusters.too easy.
now the bad news.....that low pinion puts a huge load on the pinion bearings and the teeth.also,the carrier has to be made very small to clear that pinion bearing hanging into the carrier space.as the diff was so popular,the aftermarket has addressed these issues.doesnt help the 'stock' urguement,though.
the 8.8 is a very good rear end.it's biggest issue seems to be the forward pinion bearing prematurely wearing,and the material that comes off it taking out everything else.
but the biggest thing is that it ,as has been pointed out,has little room for improvement.
just take a look in the aftermarket and see how many outfits are selling 35 or 40 spline axle upgrades for it
those are common for the 9''.
it's not so easy to set up on the bench either,or carry a few different setups so you can drive to the race with 3.07 gears and an open diff,swap to a 4.56 spooled for the event,then back to street gears for the trip home.
this bearing does give much more support,but is actually needed because the two taper bearings are very close together.on the stock car housings,the casting around this bearing has a tendency to break,and the pinion loses all it's support.this is compounded by the pinion sitting lower on the ring gear,putting more leverage on it.
ford produced a 'nodular iron' housing that toughened up the whole shebang,but that bearing was the real benefactor.aftermarket housings are even stronger,and lead to a nearly indestructable unit.
as for user friendlyness,the 9'' is king.pull the center out and stick it on the bench.try that with an 8.8.
the pinion can be shimmed without changing any bearing settings or preload,as the whole bearing assembly comes out whole,and is shimmed at the housing as a unit.
also,shims for backlash and preload don't exist.this is set with screw in bearing adjusters.too easy.
now the bad news.....that low pinion puts a huge load on the pinion bearings and the teeth.also,the carrier has to be made very small to clear that pinion bearing hanging into the carrier space.as the diff was so popular,the aftermarket has addressed these issues.doesnt help the 'stock' urguement,though.
the 8.8 is a very good rear end.it's biggest issue seems to be the forward pinion bearing prematurely wearing,and the material that comes off it taking out everything else.
but the biggest thing is that it ,as has been pointed out,has little room for improvement.
just take a look in the aftermarket and see how many outfits are selling 35 or 40 spline axle upgrades for it
those are common for the 9''.
it's not so easy to set up on the bench either,or carry a few different setups so you can drive to the race with 3.07 gears and an open diff,swap to a 4.56 spooled for the event,then back to street gears for the trip home.
