Overfilled
Thread Starter
Instructor
Joined: Jul 2020
Posts: 182
Likes: 31
From: Michigan
Overfilled
A friend of mine asked me a question the other day and I didn’t know the answer. Question is, if you overfill your synthetic oil ( Mobile 1) in your c6 6.0L, LS2 will it harm the engine? Like the other non synthetic oils, which will get frosty and break down with millions of fine bubbles being sucked up by the oil pump and not give the engine the oil it needs. I have no idea how to answer this question.
Safety Car
Joined: May 2016
Posts: 4,654
Likes: 1,837
From: Erlanger, Kentucky
If it is overfilled by a small amount, say 1/2 quart, it won't do any harm. Any more than that and I would recommend draining some out.
Now if the oil was massively overfilled like has happened to a few people with C6 Z06's, it can cause catastrophic engine damage from basically hydro-locking the engine. But we are talking adding twice the amount of oil than normal.
Now if the oil was massively overfilled like has happened to a few people with C6 Z06's, it can cause catastrophic engine damage from basically hydro-locking the engine. But we are talking adding twice the amount of oil than normal.
Race Director
Joined: Oct 2012
Posts: 17,338
Likes: 6,510
From: Melbourne, FL
A lot of cars can hold 2 or 3 quarts over their rated capacity. My TBSS for instance is also an ls2, with a different oil pan, rated for 6 quarts but due to a poor design its recommended to run 7 to 7.5 quarts. The extra oil helps prevent starvation when launched.
Safety Car
Joined: Aug 2017
Posts: 4,924
Likes: 2,334
From: Etobicoke (Toronto) Ontario
This is out of the 2007 owner's manual, so it applies to the LS2.
"Except Z06: Be sure to check the oil level
often during racing or other competitive driving
and keep the level at or near 1 quart (1 L)
above the upper mark that shows the proper
operating range on the engine oil dipstick.
After the competitive driving, remove excess
oil so that the level on the dipstick is not above
the upper mark that shows the proper
operating range."
So if it's safe to operate with an extra quart for competitive driving according to GM, there's your answer. As to why you're supposed to remove the extra quart after is a mystery.
BTW, the owner's manual for my LS3 wet sump pretty much states the same.
"Except Z06: Be sure to check the oil level
often during racing or other competitive driving
and keep the level at or near 1 quart (1 L)
above the upper mark that shows the proper
operating range on the engine oil dipstick.
After the competitive driving, remove excess
oil so that the level on the dipstick is not above
the upper mark that shows the proper
operating range."
So if it's safe to operate with an extra quart for competitive driving according to GM, there's your answer. As to why you're supposed to remove the extra quart after is a mystery.
BTW, the owner's manual for my LS3 wet sump pretty much states the same.
