92 tsi making strange ping noise around rearend

[jmills187]

some of the earlier posts dont quite explain the symptom but once i start the car up its fine once i start to move forward there is a loud ping sound ( like an aluminum bat hitting a metal fence post ) kind of every foot or two and not quite sure where to look

 

[steve]

Does it make the same sound up on jack stands when you rotate things?

 

[jmills187]

I couldnt hear it jacked up.. the driveshaft running through the carrier bearing looks to be sagging a bit but all i heard while rotating the tires by hand was the rear brakes lightly dragging on the rotors (normal)
the driveshaft would start to rotate and then not rotate past about an inch but the tires would continue to spin alternate direction... kinda lost as to what it is besides possibly carrier bearing plus being a bigger kid it will be a pain getting to the carrier since its dead in the middle of the car

 

[steve]

Unbolt the drive shaft to diff flange and see if it's the DS or Diff.

 

[jmills187]

do i pull the bolts to the flange and just rotate the tires or start the car and move it?

 

[steve]

I'd do it by hand. Running the car with the rear of the DS unsupported sounds like a quick disaster.

Why couldn't you move the DS more than 1"?

 

[jmills187]

jacked up the rear end and disconnected the drive shaft and then seperated them moved the ujoint an flange over .. spread my arms and made both tires go same direction... sounds faint but i still think rearend

 

[jmills187]

well I got home today after work and pulled the drain and fill plug... sure enough tons of metal shavings.. and a few chucks in the drain pan... now if there was only a way to get the 4 hub bolts/nuts loose!??!!?!?

 

[steve]

, draining the fluid looking for chunks would have been a good place to start...

 

[jmills187]

yeah but tried to pinpoint noise first to make sure where and what then eliminate things after that... without spending money

 

[steve]

Is there an easy way to brake the 4bolt axles from the hub?
Are they just flat to flat mating surface with 4 bolts through them?
I found my big prob though, the pinion gear had like 3 to 4 teeth broke completely off.
Where would i go about ordering a new ring set and pinion from?

The flanges are flat, I found when I did my 4 bolt conversion that the outer CV joint seal had stuck to the hub flange and I pulled it off trying to detach the axle from the hub flange. If the flange had been attached to the hub a minor adjustment with a BFH should have sheared the bond and split the two.

While it's likely you might be able to find new old stock somewhere I remember people saying that the pinion and ring are the same between the 3 and 4 bolt versions and it's easier to find a used 3 bolt diff cheap and swap them on the 4 bolt diff and reshim.

Is yours a VC based LSD or an open diff. If it's open you might want to just swap to the LSD rear end and matching axles. Keep in mind that there is a ratio difference between manual and auto's so you need the correct gear set.

 

[jmills187]

yeah just lookin to rebuild this 4 bolt for a spare, i ordered a new used 4bolt for a decent price. I think i may take a couple pics and make a small write up

having an issue trying to seat the axles into the diff all the way til they are flush.... any suggestions?!

had a hard time seating the axles in the diff... used a block a wood and a rubber mallet and a sprinkle of get @$#% done and voila... completed just rigging up a way to fill the rear differential with fluid