Somehow I introduced more driveline slop???

[golfprowanabe]

I had a performance shop reseal my differential, and a month later it leaked worse than it was before. Turns out they stripped out two of the ten bolts holding the cover! Ok, I can understand stripping them out, but c'mon, fix it. They just left them stripped.
So I decided to do it myself. No biggie, I only sent it to the shop cause I really didn't have the time. Lesson learned. I decided to order the new performance cover from Ford and install it. I helicoiled the two stripped out holes and started tightening all the bolts. Got to the last one, and it wouldn't hold the 25lb required torque. So screw it, I helicoiled all of them!
Anyhow I re-installed everything back to the way I thought it was, even watching how many washers were above and below the diff. front mounts. The diff is sealed up nicely now. Not a drop (also thanks to that new gasket I got). But I have noticed quite a difference in how much slop is now in the drivetrain. How could have I introduced additional slop? I didn't touch the gears in the diff. Any ideas on what I could have done?

 

[10sec89]

Did you remember the two mount bolts at the rear of the cover?

 

[golfprowanabe]

Are you talking about the 'tension' bolts on the new cover. The bolt itsself to be torqued to 5lbs and the locknuts around those bolts at 35lbs. I did torque these bolts down.

 

[10sec89]

I would get back under it and put a wrench back on everything that was removed to see if everything is tight, other than that? Let us know what you find.

 

[golfprowanabe]

Just got under it and everything is lock tight. But with the car in neutral, i can twist the drive shaft maybe 15 degrees back and forth before the wheels start moving. That sems like a whole lot to me! Now I don't know if that's from the transmission side or the differential. The driveshaft bolts are in there solid so its not like it's moving against the front of the diff. Can something wear out inside the diff to cause such slop?

 

[golfprowanabe]

Ok... after re-inspecting the bolts by torqueing with a wrench (note to self... had checking doesn't cut the mustard!), I found that the front mounting bolts were a bit loose. One of them needed a good two rotations of the nut to tighten.
It's kind of surprising that would cause all the slop I was feeling, but it was. Everything feels good now. I guess that 15 degree free rotation of the driveshaft can hardly be felt.

 

[DocB]

Interested.

Which two front mounting bolts were loose?

Do you still have the 15 degrees of rotation of the driveshaft?

 

[golfprowanabe]

Interested.

Which two front mounting bolts were loose?

Do you still have the 15 degrees of rotation of the driveshaft?

The ONLY two front mount bolts for the differential housing. These bolt to the bracket. They are the ones that have washers to adjust the pinion angle.
Yes I still have the 15 degree rotation. Can't really feel THAT at all while driving.