Why does shop fill Oil above FULL level?

[Don in Austin]

Originally Posted by adriver

I'm guessing it wasn't leaking before. (its not a coincidence they didn't mention it the first time they were under it looking at it). I would think its your rear main seal, and YES it is probably from them overfilling your oil. This is something they should be required to fix for free. Have you noticed an increase of oil where you park?

I know of no mechanism by which overfilling the crankcase could damage the rear main seal.

Don in Austin

[GNCamry99]

Originally Posted by adriver

I'm guessing it wasn't leaking before. (its not a coincidence they didn't mention it the first time they were under it looking at it). I would think its your rear main seal, and YES it is probably from them overfilling your oil. This is something they should be required to fix for free. Have you noticed an increase of oil where you park?

Why do you point to rear main seal? Do you have a documented facts to support overfilling cause rear main seal leak?


I find the rear main seal fixing a major work that needs transmission/engine related skills.

This shop did not handle the oil change correctly. How do I expect a good work from this shop on fixing rear main seal leak?

When the shop took out 1.25 Q OIL. They loosened OIL filter then drain plug. They tighten the OIL filter/drain plug after taking out 1.25 Q oil.

Did this process messed up the caskets/washers that cause this leak?

Thanks for your guidance.

[GNCamry99]

Thanks for your replies/suggestions.
.
I did car wash with undercarriage wash as well. I notice oil spot on parking lot. I find one little right of OIL drain plug (1st spot) in parking lor another one just below the distributor/origin of spark plug wires (2nd spot).

I did check the spark plug after pulling the wire from spark plug. The passenger side spark plug wire (it is on the other side close to OIL Filter Cap (where the belts are. I do not know cylinder numbering. Left to right or right to left etc) shows OIL wetness, all others are OK.

I did not find such issue before this overfilling OIL. I did put some UV OIL dye. After driving couple of days, I will take it to the shop and ask them to find, where the leakage from.

What are the cause of these leakages?

Thanks for sharing.