My new long wanted S-Type was purchased just about a week ago but I am going thru some struggles with it just failing an annual inspection.

There are a number of things to be fixed and the leak of the differential is one of them.

I was thinking that could I simply apply an "stop leak" product and call it a day?
They are made to at least stop some leak, maybe only small ones though, but the cost difference between the stop leak application VS garage charge are tremendously big that I am hoping that there is a hope for use of such chemicals.

Has anyone heard of it being useful for such leak around differential part(s)?

If so where do I add the chemical? Do I add to the transmission box?

Best,

 

Depends on what part of the differential its leaking from, might just need a new seal which are inexpensive, and not a major to do. Do you have any pictures of the leak?

 

Unfortunately not. But it appears that the leak is caused from the long pipe that goes into the differential and not actual differential.

 

Is this job a DIY worthy?? I have been changing control arms and suspension kits. And that's as much as I can DIY but anything related to transmission/oil sound/look little too advanced.

 

do you mean the driveshaft?

 

For a rear end leak the only solution is to repair it. There are no wonder stop leak products in a can that will do anything for you.

Have you checked the level?

I think you are talking about the oil coming out the vent?
This is hard to see and is on the right side on top of the pumpkin.

Just a note? On my 2005 STR I changed the rear end fluid and got a small seep afterwards. Never did find where it was coming from but it looked like the vent.

I opened the fill plug and took a bit more fluid out and have had no seeps since then. I must have slightly over filled it.
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