When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Oil pan leak after full replacement of gasket… Help!
My 2006, A6 has 126,000 miles. The original oil pan and gasket started leaking significantly around 124,500 miles to where the oil would blow back onto the exhaust and burn off, then the smoke would come into the cabin. About 500 miles ago I finally was able to do a full gasket replacement on the oil pan. I wasn’t able to do it with my work schedule so my dad and one of his mechanic friends did it together as he has a small shop with a two post lift. We used all OEM parts. After taking it on a small road trip for a few hundred miles I checked underneath and sure enough there was oil residue coming down the passenger side of the oil pan.
Now a couple hundred miles later it is leaking again significantly from the passenger side and one small area right above the oil filter on the driver side. It’s about the same flow rate as it was right before I did the repair. I’m pretty baffled as to why it would do this again and I’m hoping to avoid having to do another full gasket replacement.
Has anyone experienced this before or have any ideas of how to fix this without doing another full gasket replacement? Any help as much appreciated.
Since the oil is leaking at about the same rate as before, I am led to believe that the leak might not be coming from the oil pan gasket at all. The leak might be coming from the bolts on the side of the block that secure the main bearing caps to the skirt in the block. Those bolts are sealed at installation with the use of silicone under the head of the bolt, but it is not unusual for them to leak after time and mileage has taken its toll. If you can determine that indeed the leak is coming from one or more of those bolts, the fix it to remove the bolts, clean everything up real good, apply silicone under the bolt heads, and reinstall the bolts. Note: You might need new bolts if they are torque to yield type.
Since the oil is leaking at about the same rate as before, I am led to believe that the leak might not be coming from the oil pan gasket at all. The leak might be coming from the bolts on the side of the block that secure the main bearing caps to the skirt in the block. Those bolts are sealed at installation with the use of silicone under the head of the bolt, but it is not unusual for them to leak after time and mileage has taken its toll. If you can determine that indeed the leak is coming from one or more of those bolts, the fix it to remove the bolts, clean everything up real good, apply silicone under the bolt heads, and reinstall the bolts. Note: You might need new bolts if they are torque to yield type.
Thank you. That is definitely a good theory. Do you have a photo (or could point me to one) of what these look like when under the car?
Thank you. That is definitely a good theory. Do you have a photo (or could point me to one) of what these look like when under the car?
Just go on Youtube and search for LS2 engine rebuilds (any LS engine, actually), and see how they insert and torque the bolts for the main bearing caps. Then you will know how to find them. They are pretty easy to find. Even if you just looked at the area just above your oil pan, you should see those bolts lined up in a row along the block.
Other than what you mentioned above about adding silicone under the bolt heads, is there any special procedures to replacing them while the engine is in the car?
(the videos and discussion I see is all about doing so with the engine out and being rebuilt which is not my current scenario)
Oil pan leak after full replacement of gasket… Help!
