DFI, Batch Fire, and other myths

[Gary Derian]

I accept that a weak crush sleeve limits the pinion flange torque which may
allow it to loosen, a good point that is, too, but gear loads are not
transmitted through the crush sleeve.

Gary Derian <gderian at cybergate.net>

>>Not quite right......
>>
>>The crush sleeve is used to set the front and rear pinion bearing
pre-load,
>>the front pinion bearing takes the thrust from the driveshaft. If the
>>pinion nut comes loose then the pinion will move rearward and instantly
>>chew the ring gear.
>>
>>/Marc
>
>The front bearing also takes the gear thrust when the gears are loaded on
>the coast side of their teeth. (like with regular cut gears, driving
>forward in the front end of a 4x4)
>
>One main point is, that with a crush sleeve, tightness of the nut is
>limited, so it is way more likely to come loose---
>
>Greg
>>
>>The way I know, the crush sleeve is only used to hold the inner bearing
>>races against the pinion gear to keep the races from rotating relative to
>>the pinion.  It doesn't take any gear loads.  You could remove the crush
>>sleeve and loctite the inner races to the pinion.
>>
>>Gary Derian <gderian at cybergate.net>
>>
>>>
>>>Betcha it was a crush sleeve. The too long driveshaft pounded the
>>companion
>>>flange on the pinion into the sleeve hard enough to smush the sleeve
>>beyond
>>>where it was supposed to be, and the rest was history. No doubt the too
>>>long shaft was what got the rear mount bolts too (before you fixed them!
>>>
>>>The crush sleeves are cheap for the mfgrs to use in a production
>>>situation--beyond that they are not worth a #@$% !!!! For any performance
>>>application, or even just for a quality rebuild, a conversion to positive
>>>pinion preload shims is HIGHLY recommended for ANY rear axle!!!
>>>
>>>Regards, Greg