U-joint? I'd disconnect the driveshaft and check.

 

What is it spraying? Oil or something dry?

Our cars don't use U joints, but a rubber doughnut that connects the shafts to the drive line.

 

Forgot about the rubber doughnut. Duh (on me).

 

How did that leak evolved or solved ?

Seems I see some similar issue

See picture below

 

Car has taken 1st place 2 yrs now D-11 class Concorse’De Elegance

I have not done anything at the moment. I have been trying to locate a Quafie rear for it. Actually another housing and rebuild it with Quafie assembly, seals etc and do an entire diff changeout.
It does not drip onto the garage floor. I did have the fluid changed out which was really dark. I have an BMW/Mercedes independent mechanic about 2 miles from house really sharp and v reasonable. I’d have him do it. We already discussed. I’m getting to old to work without a lift.
I spkoe to the Jag dealer here and they said $425-500 to fix the leak. If it’s not dipping I’m leaving it until I get another diff.

 

I tend to agree that no drip is no leak but still want to be ready for the drip which will probably follow...

I think I will buy the pinion seal and new fluid and take care of them both once I'm in there.
Not sure if the shaft need to be completely removed for changing the seal or just remove the rubber doughnut ?

BTW what fluid for the 4.2L N/A ?

 

DannyJ, you are leaking around the nut that holds the yoke onto the pinion shaft. The '03 and up Lincoln LS diff is a direct swap and you can get 3.31 or 3.58 gears. I went with the gears and haven't felt the need for a posi unit yet. I have pics in my build thread of the swap. Overall not a hateful process.

 

Ranchero,
Can you send / post the link to your direct swap to the Lincoln Limited Slip diff.

Danny as Ranchero stated per the pics it’s NOT you yoke shaft seal (pinion). As for fluid I used 75/140 full synthetic.

 

Thanks Ranchero for the suggestion to swap the diff but I'm afraid LS cars are not popular here around so I will stick to the current diff

I did read you thread anyway. Great info and writing
If the leak is from the nut area will it be enough to remove the yoke and put some RTV on the pinion or is it the oil seal behind the yoke which should be changed anyway ?

 

Yes, I understand that but still not sure how oil could be leaking through the nut without a bad oil seal ???

Thanks for the oil code

 

I want to say there's a molded O ring into the nut's face to seal the pinion spline to yoke fit. I think I have the spare floating around and will check it when I get home.

 

Great Ranchero, I will really appreciate it

 

Well 56$ seal $1282.00 total at dealer in Cockeysville MD.
4 different local shops all said that they needed 4-6 special tools to change the seal. It seams that seal is in it own carrier.
we’ll I don’t have to smell vaporizing gear oil now.