Sterling 10.5 Limited Slip Question

[iaff284]

I am hoping a Diff. Guru can answer a couple limited slip questions. First some background, I have an 03 Super Cab 4x2 with the 7.3L. I have been chasing a vibration that comes and goes for about 6 months now. It starts at around 25mph, gets better until 70mph plus and then it shakes the truck pretty good. It oscillates and is at its worse after 10 to 15 miles of driving. I have narrowed it down to the driveline. I have tried "balancing" the two piece driveshaft with a couple hose clamps and it helps but is still there. I have jacked up the rear and put the truck in gear and it looks like the drivers side rear is a little out of round so I thought that was it. Removed just the drivers side wheel, ran it up to 20mph and it was still there. Removed the passenger side, better but still there. Eyeballed the driveshaft while in motion and it looks like there is a little wobble down by the pinion, so I planned on taking it to be balanced. In the process of tightening down the lug nuts, there seemed to be a little excessive play in the backlash. Took a closer look at the diff and there is fluid leaking from the pinion flange and possible the rear cover. I spun the tires and both turn the same direction as a limited slip should. With the trans in park I was tightening the lug nuts and the drivers side wheel started turning. While watching the other wheel and turning by hand with the trans in park the opposite wheel will spin the opposite direction as with an open diff. My concern is that the limited slip is trashed or the pinion is loose and took out the limited slip. If the limited slip is trashed or the pinion is loose or both could that cause a driveline vibration as described above? Sorry for the lengthy post, just trying to get all the info out!

[iaff284]

Nobody??? Bump

[etnies69924]

i really dont know. i have a vibration when i let off the throttle on the highway but that was my u joint and yoke. not sure if you checked those, now would be a good time to replace them. also you would be better off getting the u bolt style yokes, i have gone through two yokes as of yesterday...oopps. right now i am looking to order all this now, here is a link to a site i found. i hope at least some of this helped!

Dennys Driveshafts and Driveline Parts Shop online from our large in stock inventory of Genuine Dana Spicer and Neapco drive shaft and driveline parts and components for cars trucks and 4x4 applications.

[01f25073]

Replace your driveline u-joints with greaseable units, pinion seal, and a rear differential service. Get a gasket for your differential cover, it makes it a lot easier and faster. This may solve your issue. When my driveline started shaking, this is what was wrong with mine.