Do M6 LS1's really burn oil like I've been hearing?
Registered User
Joined: Dec 2000
Posts: 311
From: Latham, NY
So what would have brought about this problem in the later iterations of the motor but not the earlier ones? I mean 2001 was the fourth year the LS1 had been mass manufacturered and marketed. I had always assumed that they fixed the problem in 2001, and that is was a more common problem in the earlier motors...
Registered User
Joined: Mar 2002
Posts: 82
From: fort bliss, tx
A good question, and here's the answer:
Starting in 2001 GM went to different piston rings in their LS1's. These rings are slightly narrower, and therefore the ring gap from 2-3 is larger (follow so far? good..).
The "piston knock" everybody is hearing during the first start of the day comes from the cold metal rings not seated entirely against the cylinder wall. As the engine warms, the rings expand, creating a nice tight seal. However; oil seepage does occur during the first few moments of startup everytime, because of the contraction properties of metal (no wall-to-ring seal) and at sustained high revolutions. Some f-bodies experience significant oil seepage/burning, others do not. Although the manufacturing tolerances inside the engine are very tight, they aren't exactly the same for every engine built.
Clear as mud, right?
Starting in 2001 GM went to different piston rings in their LS1's. These rings are slightly narrower, and therefore the ring gap from 2-3 is larger (follow so far? good..).
The "piston knock" everybody is hearing during the first start of the day comes from the cold metal rings not seated entirely against the cylinder wall. As the engine warms, the rings expand, creating a nice tight seal. However; oil seepage does occur during the first few moments of startup everytime, because of the contraction properties of metal (no wall-to-ring seal) and at sustained high revolutions. Some f-bodies experience significant oil seepage/burning, others do not. Although the manufacturing tolerances inside the engine are very tight, they aren't exactly the same for every engine built.
Clear as mud, right?
Registered User
Joined: Jun 1999
Posts: 2,368
From: OR
I do and feel exactly what Chris said.....
I use the small filter.. the long filter hangs down a too low for my comfort for street driving.
I use the small filter.. the long filter hangs down a too low for my comfort for street driving.
Originally posted by z28chrizz
My Z is oil consumption free. First time I ran synthetic, I had the low oil light come on as it was time for an oil change. Now, I put in 6.5 qts in during the autocross season (extra oil gets trapped in the lifter valley and valve covers... so a little bit of extra protection never hurts) and right before I change the oil it still reads full. Which means in my 3k of hard driving, it burns that
1/2 qt which is well within the tolerance for any new engine.
Some thoughts... if you guys are using the larger M1 filter, are you adding extra oil to compensate? There is a somewhat significant increase in volume (8oz ish) between the M107 and M111 (?) I believe.
If you are letting the engine rev down hard ie, rev to 5500, then let the engine braking slow the car down to say 2500 rpm... you are fluttering the oil rings and naturally going to burn some oil. That is a common problem with all cars and sustained high decelrating revs. Only time I do that is when I am autocrossing the car... rest of the time as cool as it sounds I resist and shift to a higher gear and use my brakes.
My Z is oil consumption free. First time I ran synthetic, I had the low oil light come on as it was time for an oil change. Now, I put in 6.5 qts in during the autocross season (extra oil gets trapped in the lifter valley and valve covers... so a little bit of extra protection never hurts) and right before I change the oil it still reads full. Which means in my 3k of hard driving, it burns that
1/2 qt which is well within the tolerance for any new engine.
Some thoughts... if you guys are using the larger M1 filter, are you adding extra oil to compensate? There is a somewhat significant increase in volume (8oz ish) between the M107 and M111 (?) I believe.
If you are letting the engine rev down hard ie, rev to 5500, then let the engine braking slow the car down to say 2500 rpm... you are fluttering the oil rings and naturally going to burn some oil. That is a common problem with all cars and sustained high decelrating revs. Only time I do that is when I am autocrossing the car... rest of the time as cool as it sounds I resist and shift to a higher gear and use my brakes.
Registered User
Joined: Jan 2002
Posts: 275
From: Goose Creek, SC
Originally posted by DanBUCF
I am pretty sure the problem only occurs in '01 and up LS1's.
I am pretty sure the problem only occurs in '01 and up LS1's.
Originally posted by Camaro00_ss
Starting in 2001 GM went to different piston rings in their LS1's. These rings are slightly narrower, and therefore the ring gap from 2-3 is larger.
Starting in 2001 GM went to different piston rings in their LS1's. These rings are slightly narrower, and therefore the ring gap from 2-3 is larger.
Very Very informative website! Hey if ya think im a pompuss *** imagine how SPYKE would've replied
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