8.25 for dummie (me)

[Cudaroy]

I just ordered a new basic ring and pinion install kit (RAT-400K) from Summit but something just dawned on me.
I am getting a slight hum from the rearend once warmed up. And a slight vibration more like oscillating at highway speeds. I recently had the driveshaft shortened,straightened and balanced by a reputable shop up here. I grabbed the yoke and found some slop and tried to tighten the pinion nut. I was able to get maybe 3/4 of a turn before "bottoming out" and had less slop but still some.
I thought the crush sleeve was to blame but it kinda doesn't make sense. If the sleeve is crushed and I tightened the nut more wouldn't it put excessive preload on the bearings? Or am I missing something?
Anyone out there can direct me to an exploded view of the 8.25 (1973) ?

Thanks in advance,Mike

 

[Gen2Cudas]

Bump to subscribe- got one to rebuild too!

 

[fishy68]

Your correct that if you tightened it too much the pinion bearing preload would be too much. Is this slop side to side or rotating slop? If it's rotating slop that's possibly just backlash your feeling. If it's side to side slop it's probably bad pinion bearings. The hum is also indicative of bad bearings. I always replace the crush sleeve with a crush sleeve eliminator kit. Makes the setup easier and eliminates the chance of the crush sleeve collapsing.

 

[Cudaroy]

"Slop" I am referring to is side to side. I'll know more when I remove the cover this weekend. It ain't much but enough to create the hum and oscillation. Damn, should have also got the bearings too......

Thanks