Rear Differential
Matthew12M
10-17-2004, 03:11 AM
Hey,
I've got an 88 Chevy C1500 2WD. I noticed some oil slinging around (exhaust pipes, gas tank, bottom of truck bed) where the differential meets the drive shaft. I naturally replaced the pinion seal which made perfect sense, then cleaned all of the oil around to see if the leak would continue, and sure enough it was. ( I installed the seal just like it was when I saw the old one, with the face of the seal tapped in evenly with the beginning of the opening; it wasn't pushed in any further) After I replaced the seal I noticed small amounts of oil in the same spots. Now I think my problem has to do with the torque of the pinion nut. When I took it off, it was very easy to take off (I did mark it before it was removed) with a large torque wrench. The flange came off easy without a puller aslo! I'm thinking maybe the pinion nut was too loose in the first place. The bearing was fine. I understand my design utilizes a crush sleeve, but I am unsure as to its effect on the bearing preload? So, if the nut was too loose to begin with, how could I tell. By the way, screwing the nut back on was a sinch also, which is weird because all of the sites I have seen say it was sooooo hard tightening the nut. In my Chilton book, there is a torque specification for the "pinion seal nut" and shows it to be 255 ft lbs. for GMC and 270 ft lbs for the DANA model? Should I re tighten the nut to this spec, because it was not that tight when i took it off. There was only 3 threads from the tip of the pinion shaft threads to the beginning of the nut. I understand if I over tighten it, I will ruin the crush sleeve and the bearing and have to replace both, so, I have the bolt on now at the same alignment marks as it was before the nut was off. Also, when I took out the seal, it actually didn't look bad at all.... oh and by the way, there was plenty of permanex no. 2 sealer in there! Please help...
Thanks,
Matthew Megally
I've got an 88 Chevy C1500 2WD. I noticed some oil slinging around (exhaust pipes, gas tank, bottom of truck bed) where the differential meets the drive shaft. I naturally replaced the pinion seal which made perfect sense, then cleaned all of the oil around to see if the leak would continue, and sure enough it was. ( I installed the seal just like it was when I saw the old one, with the face of the seal tapped in evenly with the beginning of the opening; it wasn't pushed in any further) After I replaced the seal I noticed small amounts of oil in the same spots. Now I think my problem has to do with the torque of the pinion nut. When I took it off, it was very easy to take off (I did mark it before it was removed) with a large torque wrench. The flange came off easy without a puller aslo! I'm thinking maybe the pinion nut was too loose in the first place. The bearing was fine. I understand my design utilizes a crush sleeve, but I am unsure as to its effect on the bearing preload? So, if the nut was too loose to begin with, how could I tell. By the way, screwing the nut back on was a sinch also, which is weird because all of the sites I have seen say it was sooooo hard tightening the nut. In my Chilton book, there is a torque specification for the "pinion seal nut" and shows it to be 255 ft lbs. for GMC and 270 ft lbs for the DANA model? Should I re tighten the nut to this spec, because it was not that tight when i took it off. There was only 3 threads from the tip of the pinion shaft threads to the beginning of the nut. I understand if I over tighten it, I will ruin the crush sleeve and the bearing and have to replace both, so, I have the bolt on now at the same alignment marks as it was before the nut was off. Also, when I took out the seal, it actually didn't look bad at all.... oh and by the way, there was plenty of permanex no. 2 sealer in there! Please help...
Thanks,
Matthew Megally
ebu187
10-21-2004, 11:59 PM
never loosen shit with a torque wrench,it wrecks them. its probably the yoke(part that blots on) might have a groove in it or might be pitted,get a new one or speedy sleeve it
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