A/T - ATF Leaking From Differential Pinion Seal Vent
TECHNICAL BULLETIN # 098DATE: Feb 92
TRANSMISSION: Type 010
SUBJECT: Vent Leakage
APPLICATION: VW/Audi
It's not uncommon to find ATF leaking from the differential pinion seal vent after an overhaul. (Figure 1) The following steps should help prevent vent leaks.
1. Make sure the differential pinion preload is correct. (See the appropriate shop manual for the model your working on.)
2. Make sure the seals fit the pinion shaft and the seal contact area is not worn.
3. Install the seals as shown in figure 2. The ridges of the seals should face each other.
IMPORTANT
Make sure you put some sealant on the outside of the seals.
4. To test the seals, draw a vacuum on the vent. (Figure 3) There should be no leakage.
Note
For clarity this picture was taken with the cover off the differential.