can someone tell me if the rear end on a 2005 jag s type is a sealed unit or is there a breather tube or vent hole.I took it in to the jag dealer put it up on hoist check the rear end fluid was ok,then the mechanic wiped off the rear end where some oil was leaking from the pinion area sprayed off rear end with cleaner said ya need pinion seal.today put the car up on some ramps to check the leak, all is still clean no leak after four days of driving maybe when he checked the oil and took out the plug it let the pressure off the pinion seal.???????HELP

 

Keep driving the car. At night put a large piece of paper on ground beneath that area to see if fluid leaks. Then you will know far sure!

 

only lasted a month,started to drip againwish i had some step by step picture and torque sets i would try it myself.

 

Any update here? Is there a breather plug/tube to check/cleaned first? I don't see one on the parts diagram. Did you end up replacing the seal or did you find other issues?

LCMJAGUAR
2008 XJ8 VDP
1988 XJ6

 

No breather tube on the S-Type rear differential. Eventually the seals wear to a point that fluid will slowly seep. Just top off fluid every 15k miles. Of course, replace seal if excessive.

 

Guys. All rear ends must be vented. The oil gets hot and expands. With out a vent system you would be pushing oil out the seals. Yes the S Type rear diff has a vent. See the factory parts diagram below. I have marked the vent and vent tube with red arrows.
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So how common is it for fluid to seep out of that vent tube under "normal operating conditions"? I would think it is there simply to be able to relieve internal pressure during conditions of higher-than-optimum heat inside the differential, and not to allow fluid to blow out of the unit....

 

Sorry Jon89. Clubairth makes good sense regarding vent.

 

A vent is usually place in such a place or angle as to not allow oil to get through it but to allow air flow out.

I saw the part number 15 (vent tube) and 16 (vent stem) on the digragm before but it does not show where on the differential it goes. I also looked at the XJ8 as it takes the same differential and that overall diagram is the same except it does not even show part numbers 15 or 16 at all. I agRee that all differentials are vented but prior to 2004 the vent was obvious in the upper rear section that stood up about 1 inch and could easly be taken off with a wrench and cleaned but after 2004 I don't see it at all.

So the question is where is it exactly, how does one have access to it, and how does one remove it and clean it to elimiate the possibility of this being clogged (which has been a common problem in the older pre 2004 air vent plug?

LCMJAGUAR

 

see that nipple at the top right of the diff cover?

 

My differential shows to be a little different than the EPC diagram regarding the air vent nipple. I can see the small nipple on the upper rear right hand side of the diagram using the S-Type but my differential looks different here. I have no nipple extruding out. Best way to see it is a picture of one that is same as mine (see Ebay link below). The metal casing looks like a vent going to the top but at the top there is no nipple and I can feel the hole if plugged by metal about 5mm down, by maybe a screw plug. Not sure what to make of it or how to serivce it. I think a design change was made.

Here on Ebay is a similar one. I also saw a picture of a brand new one and it also looks just like this used one...no nipple sticking out.

http://www.ebay.com/itm/2004-2005-20...89dc1e&vxp=mtr

Any other insight you have to rule out any pressue issue first before replacing the seal would be very helpful.
Best regards,
Len
LCMJAGUAR

 

Thanks for the picture. Seems like that vent is plugged off? But be careful as that XJ8 Ebay rear diff has a different part number (2W93-4A213-AA) than the S Type (2R8W-4384-BA). I agree they look the same but there is a reason for the different part numbers.

Here is a Lincoln LS rear suspension. It's the only picture I could come up with showing the vent and hose.

You guys got me wondering so I will crawl under the STR later to see what Jaguar did different??
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Looks like the Lincoln LS differential is the same as the EPC Diagram. A Jaguar mechanic told me that the differential between the S-type and XJ8 (for 2004 to 2009) are the same and the EPC diagrams leads one to believe this also; but we can see my differential on my 2008 XJ8 is different regarding the layout of the air vent (maybe latter model S-types are also different due to a design changed). I am reaching over to the S-Type side of the Forum because there is more talk about differentials here so any help will go a long way.

Here is a picture of a new XJ8 differential and you can see the back of the differential very clearly. The vent area casting is very different then the EPC diagram and the Lincoln LS. The end does look like a pluged style unlike the EPC digram showing a vent nipple. Not sure if my differential design vents air or how to sevice it as it is hard to get to it to confrim its function, but I know all differentials must vent air since air pressure builds as the gears turn and the oil heats up.

LCMJAGUAR
2008 XJ8 VDP
1988 XJ6

 

i had the seal replaced at the dealer end of aug.2012 check it today starting to leak again,now back to the dealer.have to tell them check the breather tube ?.started today with emergency brake was faulting would not let the brakes off,had to disconect batt. pos. for 10 min. to reset then the brake was ok,cheked battery 11.9 volts had to replace battery not cheap 250,was told when battery low will cause this to happen. only - 26 just little cold

 

With it that cold, perhaps the battery was just weak, but no dead cells?

 

on the rear end on mine looks the same,i tried to mirror it to see but looked like something was blocking hole,took small wire to see if i could poke in the hole no luck maybe screen there?

 

Hi

Digging up an old thread. I have a somewhat leaking diff, tried searching for a vent tube, but didn't find one? Diff has a code on it - 2R8W-4384-BA.

It seems that the leak is coming from the top. Any hints, instructions would be appreciated, thanks!