I just noticed that there was a little fluid near the driver's side of the differential, on the suspension crossmember, the sway bar, and the underside of the tub. I checked on here, and found that the C5's are known for leaking driver's side differentials. So, I took out the fill plug to see if the level was low, and nothing came out. So, I started putting some fluid in, and got a few (4? 8?) ounces of fluid in, and it started coming out. It didn't seem to be significantly low, so I guess the seal isn't real bad yet.

When I removed the plug, though, I heard a little air flow around it, as if there was pressure inside the diff. Where is the relief valve or whatever it has, and what does it look like? Could mine be clogged?

The car has about 15,000 miles, and doesn't see much rain (but a little every now and then). I don't drive like a crazed lunatic, but it has been above 100 a handful of times (well, maybe 2 handfuls).

I wiped off the fluid, and will check again in a few weeks. If it's leaking, I'll take it in to get the seals replaced. (How likely are they to put in 3.90s since they will already have the entire rear end out? :D )

 

The vent is located on the top of the differential case toward the right side. It is about a 1/2" in diameter and sticks up about3/4". I'm not sure if it screwed or pressed into the case.

 

This could (probably did) cause some "venting." Mine did this, and then settled down, when I did........ :D Clean the area and keep an eye on it. Chances are it will not retrurn. :skep: We hope.

 

Most differential leaks turn out to be the left side cover and a small bead of RTV sealer fixes the problem Removal of the diff. is not necessary so changing the gears at no cost is out of the question.

 

what you heard is probably a vacuum suck. When the unit is hot, the vent releases excess pressure, but when it cools down it creates a slight vacuum. In theory, this should help keep fluid in, as well.

That being said, there is always a chance your vent it stuck.

Dave

 

Yep, vent has a check valve in it.

 

:iagree: It is normal to hear a vacuum when you remove the plug :yesnod:

 

Yes, mine also has hissed when removing the fill plug. I thought there was a check valve as the vent. Before you have them do major surgery on the differential, have them torque the driver's side plate cover bolts. Mine were slightly loose. It hasn't leaked for two weeks now, even in very hot weather. I'm keeping my fingers crossed.

 

what is RTV? How do you put the RTV on the inside of the cover? Do you take the cover bolts out and slide the cover away from the case enough to get the RTV around the inside of the cover? Is there a gasket between the cover and the case? If so, does it tear when you separate cover from the case? As you can see, I need a "How to". :D :D

 

http://home.bellsouth.net/p/s/commun...pid=109615&ck= Go here and click on the photos and your questions will be answered