New here - had been over at Pirate but this site seems to be a better fit Here's my dilemma... I have a stock '88 Suburban 4X4. On the way home from work on Friday, I noticed a slight vibration and a "geary" noise upon decelleration to stopping. Sounded like it was in 4wd, but not. Got it home checked all fluids, hubs, and transfer case to no avail. Upon turning the driveshaft to check the u-joints, I noticed a lot of slop in the pinion on the rear end. The lock nut had come loose - the driveshaft (no carrier bearing) slid back and forth close to 1/2". Seal not leaking. So I tightened the nut back up, test drove it, and all quite now. Just wondering should I worry about having caused damage to the gears and bearings by running it loose? Also, what is the nut to be torqued to? I see no place for a cotter pin like some - should I get a new nut or use Locktite to prevent this from happening in the future? Also, what gear lube to run in a NP208? Thanks in advance!