I woke up this morning and found a puddle of ATF under my car. I put it up on ramps and couldn't find where the leak was coming from, but it looks like the leak was on top somewhere because the atf was running down from the overaxle exhaust pipes. Last night just before I came home I got on it pretty good and it chirped the tires in 2nd gear which I don't think it had done that before. Any help, suggestions, opinions, anthing???

Thanks,
Manny

 

You did not just recently fill up the differential, did you? If you did, it is normal for a little to come out the vent.

If not, you have the not so uncommon diferential side cover leak. Do a search, many threads on it.

Here is the TSB on it:

Document ID# 901212
1998 Chevrolet/Geo Corvette


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SMU - Revised Side Cover and Gasket Replacement (RH)/Differential Carrier Cover and Seal Replacement - Right #02-04-20-003 - (Jul 18, 2002)
Revised Side Cover and Gasket Replacement (RH)/Differential Carrier Cover and Seal Replacement - Right
1997-2002 Chevrolet Corvette

This bulletin is being issued to revise the Side Cover and Gasket Replacement (RH)/Differential Carrier Cover and Seal Replacement - Right procedure in the Rear Drive Axle sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.

The following information has been updated within SI2000. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.

Side Cover and Gasket Replacement (RH) (1997-2000 Model Years)/Differential Carrier Cover and Seal Replacement -- Right (2001-2002 Model Years)
Tools Required
J 36797 Output Shaft Seal Installer
J 42168-16 Spacers
J 42170 Bearing and Race Installer
J 42194 Bearing and Race Remover
Removal Procedure



Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Remove the RH rear tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
Remove the RH wheel drive shaft. Refer to Wheel Drive Shaft Replacement in Wheel Drive Shafts.
Remove the RH muffler assembly. Refer to Muffler Replacement in Engine Exhaust.
Drain the fluid from the differential. Refer to Lubricant Change.
Clean any dirt or debris from around the differential cover (right).
Remove the bolts retaining the differential cover (right).
Remove the transmission vent tube retainer (automatic transmission).
Remove the differential cover (right) from the differential.



Remove and discard the axle seal (1), and O-ring seal (4) from the differential cover (right).



Install the J 42194 into the differential cover (right), in order to remove the bearing race and shims. Position the cover into a hydraulic press.



Using a hydraulic press, remove the bearing race (1) and shims (2). Mark or tag the shims for assembly.




Important
Whenever service requires the replacement of the right side differential cover, the covers MUST be measured and the right side shim pack adjusted to compensate for machining tolerances between the two components. Failure to perform this measurement procedure may result in improper differential bearing preload.


Use a caliper (2), a straight edge (1), and J 42168-16 (3) in order to measure the NEW differential cover bore dimension. Record the measurement as value A.
Use a caliper (2), a straight edge (1), and J 42168-16 (3) in order to measure the old differential cover bore dimension. Record the measurement as value B.
Subtract value B from value A. If the computation is a positive value, add shims equal to the value, to the existing shim pack. If the computation is a negative value, subtract shims equal to the value, from the existing shim pack.
Installation Procedure



Install the selected shims (2) and the bearing race (1) to the NEW cover (right).



Press the shims and bearing race into the NEW cover (right) using the J 42170 and a hydraulic press.



Clean the O-ring sealing surface on the differential cover (right) and the differential housing.
Install a new O-ring seal (4) to the differential cover (right).



Install the differential cover (right) to the differential.

Notice
Refer to Fastener Notice in Cautions and Notices.


Install the differential cover (right) retaining bolts. Tighten
Tighten the differential cover (right) retaining bolts to 25 N·m (18 lb ft).





Install the axle seal into the differential cover (right) using J 36797.
Install the transmission vent tube retainer onto the vent tube, then position the retainer to receive the retaining bolt (automatic transmission).
Fill the rear axle differential with the proper fluid and to the proper level. Refer to Lubricant Change.
Install the RH muffler assembly. Refer to Muffler Replacement in Engine Exhaust.
Install the RH wheel drive shaft. Refer to Wheel Drive Shaft Replacement in Wheel Drive Shafts.
Install the RH rear tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
Lower the vehicle.

 

Where is the vent located?

 

High on the side cover. Some people think that this vent gets pluged, and pressurizes the differential and causes the side cover to leak.

 

If it's red-colored then it's ATF but both the A4 and MN6 use ATF. Sounds like your spillage is from the vent on top of the tranny.

That black tube is the vent on the manual tranny.


And there it is on the A4.