L99/LS3 engine oil leak - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

wernergmhtp · 08-28-2016, 10:28 PM

Oil is leaking from between the engine and transmission. Could be the rear main seal, oil pan, or even the gasket for the rear engine cover. The bottom of the oil pan ends up wet because of this issue, too.

Is anyone else having this problem, and is it common / what is the fix?

Note: my car has less than 6,000 miles but does see road course use.

alrock · 08-28-2016, 11:34 PM

I just had the crank sensor replaced under warranty for an oil leak. Considering how quickly the service adviser jumped to that as a likely cause for the leak, it might be a somewhat common issue.

JerTM · 08-29-2016, 10:31 AM

I have replaced a lot of oil pan gaskets on LS engines over the years. I don't think the really long bolts on the back of the pan stay tight for long and end up leaking at the back of the pan. I have yet to replace a rear main, but it is possible to be leaking. Take it in to the dealer and let it be their problem, unless you aren't under warranty anymore.

wernergmhtp · 08-29-2016, 12:34 PM

Quote:

Originally Posted by JerTM

I have replaced a lot of oil pan gaskets on LS engines over the years. I don't think the really long bolts on the back of the pan stay tight for long and end up leaking at the back of the pan. I have yet to replace a rear main, but it is possible to be leaking. Take it in to the dealer and let it be their problem, unless you aren't under warranty anymore.

Shit, I just took the car off the lift, maybe I should have checked the tightness of those bolts. I would really, really prefer not to go to the dealer for this - or anything, for that matter - even though I'm still well within warranty.

JerTM · 08-29-2016, 01:45 PM

If you put it back on the lift, loosen the two lower bell housing bolts, re-torque all the oil pan bolts and then torque the bell housing bolts back in. It may not stop the leak, but it's certainly worth a try.

ron123 · 08-29-2016, 05:52 PM

Also, the oil cooler flange/gasket where it mounts near the back of the oil pan up near the oil filter is another good place to check for leak.
Here is a thread I made for that area, with pictures:
http://www.camaro5.com/forums/showthread.php?t=429029

Here is sample picture from that thread:

Chevy bulletins often instruct dealers not to attempt repairs unless there is an active leak, not repair for weeping or minor seepage. If it is leaking in the area of the blue arrow in above pic, sometimes lightly tightening up the two bolts near that arrow will stop it (bolts are threaded in to soft aluminum so care is needed).
Ron

GeorgeM · 09-05-2016, 07:34 PM

If you are not under warranty (like me), I gave up on oil leaks and simply wipe the garage floor every couple of days.

I had the oil cooler replaced, and the outlet pipe gasket replaced, didn't leak anymore until the warranty expired.

GeorgeM
2010 SS 6 spd., only 21,000 mi.

wernergmhtp · 09-05-2016, 07:38 PM

I figured out the leak is coming from under the intake manifold and running down the back of the engine from there. Anyone else have this problem?

JerTM · 09-05-2016, 08:35 PM

Probably the engine oil pressure sensor, could be the valley cover gasket too.

GenesisCoupe · 01-15-2022, 06:24 AM

Sorry for updating really old posting. 2011 L99, 6L80, 100.000 miles.

10 days ago I changed oil 5w30 and filter. Today I occasionally found oil signs on the transmission and at the below side of the engine . Looks like that it is coming somewhere from upper side but I am not sure. Oil change specialist also could not say where it may come from.

I attach images, maybe you had a deal with this and could advise something...

Name: scr1.jpg
Views: 1631
Size: 176.1 KB

Name: scr2.jpg
Views: 1654
Size: 176.8 KB

Name: scr3.jpg
Views: 1553
Size: 155.2 KB

Name: scr4.jpg
Views: 1618
Size: 165.6 KB

1JEWLDSSRS · 01-15-2022, 10:06 AM

Check the back side of your valve covers. I had a leak once running down the back of the engine, and it was a bad valve cover gasket on the drivers side. Just one thing it could be.

GenesisCoupe · 01-15-2022, 01:20 PM

Quote:

Originally Posted by 1JEWLDSSRS

Check the back side of your valve covers. I had a leak once running down the back of the engine, and it was a bad valve cover gasket on the drivers side. Just one thing it could be.

Thank you.

Its a small panel under the ignition coils? On the third picture under that panel i can see old signs of oil.

0stones0 · 01-15-2022, 01:35 PM

Quote:

Originally Posted by GenesisCoupe

Thank you.

Its a small panel under the ignition coils? On the third picture under that panel i can see old signs of oil.

The cover (panel as you mention it) under the ignition coils and the bracket the coils are attached to. Which is know as the valve cover. That gasket under that cover could be the issue.

GenesisCoupe · 01-15-2022, 02:16 PM

Quote:

Originally Posted by 0stones0

The cover (panel as you mention it) under the ignition coils and the bracket the coils are attached to. Which is know as the valve cover. That gasket under that cover could be the issue.

Thank you sir. I went to the car wash with lifter and cleaned that area. Drived for a 100 miles but nothing happens. I will replace both gaskets anyway. Thanks for assisting

08-28-2016, 10:28 PM	#1
wernergmhtp Drives: 2014 Camaro 1SS/RS A6 Join Date: Jun 2014 Location: NC Posts: 119	L99/LS3 engine oil leak Oil is leaking from between the engine and transmission. Could be the rear main seal, oil pan, or even the gasket for the rear engine cover. The bottom of the oil pan ends up wet because of this issue, too. Is anyone else having this problem, and is it common / what is the fix? Note: my car has less than 6,000 miles but does see road course use. __________________ Chris Werner Author, "How to Rebuild GM LS-Series Engines" Contributing Editor, GM High-Tech Performance (1998-2014)

08-29-2016, 05:52 PM	#6
ron123 Drives: 2014 2SS/RS Join Date: Dec 2014 Location: Raleigh, NC Posts: 1,053	Also, the oil cooler flange/gasket where it mounts near the back of the oil pan up near the oil filter is another good place to check for leak. Here is a thread I made for that area, with pictures: http://www.camaro5.com/forums/showthread.php?t=429029 Here is sample picture from that thread: Chevy bulletins often instruct dealers not to attempt repairs unless there is an active leak, not repair for weeping or minor seepage. If it is leaking in the area of the blue arrow in above pic, sometimes lightly tightening up the two bolts near that arrow will stop it (bolts are threaded in to soft aluminum so care is needed). Ron __________________ 2014 2SS/RS, Z28 CAI and High Wing Spoiler, ZL1 5.1:1 Ratio Short-Throw Shifter, ZL1 Pedals, ZL1 splash guards, NPP Dual-mode quad tip exhaust, Z28 strut tower brace, Camaro LED Cup-holders with footwell Lighting option, Leather visors, and Leather E-brake boot. Chevy dealer sponsored 67 retro SS nose stripe package.

09-05-2016, 07:38 PM	#8
wernergmhtp Drives: 2014 Camaro 1SS/RS A6 Join Date: Jun 2014 Location: NC Posts: 119	I figured out the leak is coming from under the intake manifold and running down the back of the engine from there. Anyone else have this problem? __________________ Chris Werner Author, "How to Rebuild GM LS-Series Engines" Contributing Editor, GM High-Tech Performance (1998-2014)

01-15-2022, 10:06 AM	#11
1JEWLDSSRS Drives: 2011 SS-RS Join Date: May 2011 Location: FLORIDA Posts: 14,034	Check the back side of your valve covers. I had a leak once running down the back of the engine, and it was a bad valve cover gasket on the drivers side. Just one thing it could be. __________________ TSP STAGE 3 CAM,231/246 @112 LSA 614/641 LIFT, CIRCLE D 5C-4200-4500 CONVERTER,LOD INTAKE.CORSA EXHAUST. DSS 1 PC DS. PEGASUS SOLID CRADLE MOUNTS. 486RWHP/475RWTQ.LOTS MORE.

08-28-2016, 11:34 PM	#2
alrock Drives: 2015 Camaro Convertible 2SS RS Join Date: Jun 2016 Location: Scottsdale, Arizona Posts: 94	I just had the crank sensor replaced under warranty for an oil leak. Considering how quickly the service adviser jumped to that as a likely cause for the leak, it might be a somewhat common issue.

08-29-2016, 10:31 AM	#3
JerTM Drives: 2011 2SS/RS M6 Join Date: Oct 2015 Location: Utah Posts: 1,940	I have replaced a lot of oil pan gaskets on LS engines over the years. I don't think the really long bolts on the back of the pan stay tight for long and end up leaking at the back of the pan. I have yet to replace a rear main, but it is possible to be leaking. Take it in to the dealer and let it be their problem, unless you aren't under warranty anymore.

08-29-2016, 01:45 PM	#5
JerTM Drives: 2011 2SS/RS M6 Join Date: Oct 2015 Location: Utah Posts: 1,940	If you put it back on the lift, loosen the two lower bell housing bolts, re-torque all the oil pan bolts and then torque the bell housing bolts back in. It may not stop the leak, but it's certainly worth a try.

09-05-2016, 07:34 PM	#7
GeorgeM Drives: 2016 2SS, Yellowjacket, A8 Join Date: Oct 2009 Location: Pembroke Pines, FL Posts: 133	If you are not under warranty (like me), I gave up on oil leaks and simply wipe the garage floor every couple of days. I had the oil cooler replaced, and the outlet pipe gasket replaced, didn't leak anymore until the warranty expired. GeorgeM 2010 SS 6 spd., only 21,000 mi.

09-05-2016, 08:35 PM	#9
JerTM Drives: 2011 2SS/RS M6 Join Date: Oct 2015 Location: Utah Posts: 1,940	Probably the engine oil pressure sensor, could be the valley cover gasket too.

01-15-2022, 06:24 AM	#10
GenesisCoupe Drives: 2011 Chevy Camaro 2SS A/T Join Date: Feb 2020 Location: Swiss, Geneva Posts: 71	Sorry for updating really old posting. 2011 L99, 6L80, 100.000 miles. 10 days ago I changed oil 5w30 and filter. Today I occasionally found oil signs on the transmission and at the below side of the engine . Looks like that it is coming somewhere from upper side but I am not sure. Oil change specialist also could not say where it may come from. I attach images, maybe you had a deal with this and could advise something...