: Anyone Installed a Catch Can on the 3.6 LLT?

10-21-12, 05:33 PM
I'm sure everyone has read about the reputation of the 3.6 eating oil. We purchased our 2010 with the 3.6 about 8 months ago with 27k miles. I was well aware of the reputation concerning the oil. Since then we have put about 3k miles on the car and I check the oil at every fuel change. I have not seen even the slightest change in oil level. It checks out at the exact same place on the stick. Checked the intake plenum and it's pretty nice. Have others seen a rapid and instant change at some point? The engineering of the catch can makes perfect sense the DI motor doesn't have the advantage of cleaning solvents spraying on the intake valve. But mine seems just fine. Just curious if the catch can would be a wise investment.

10-21-12, 07:11 PM
A catch can is usually only used in extreme high performance situations; i.e., such as a high stress turbo and is designed to capture blow by. I am not sure what you are trying to accomplish as the 3.6 does not have a history of high oil consumption like the N* engine, and with the low miles on your STS, unless something catastrophic occurred in the past, such as running the engine w/o oil, blow by should be insignificant. Also, the assumption is you are using synthetic (Mobil 1) oil?

10-21-12, 08:57 PM
Sorry Buzz, many member posts refute your position. Were I an owner of any 2005 & up GM 3.6 V6 in any car, I would strongly consider options to limit/monitor oil foaming. I'd also want to be alert for timing chain wear.

Spend some time in the CTS forum.

PS: The N* in the STS may surprise you in how little oil use use is typical. Like all cars, the first 10,000 miles matter most. Use of the proper oil at recommended intervals always helps. In my experience, the N* thrives with hard use.

10-22-12, 04:13 AM
I am not sure what you are trying to accomplish as the 3.6 does not have a history of high oil consumption like the N* engine

Think you got that a bit backwards...LY7 and LLT are notorious for oil consumption, as well as busted timing chains due to low oil level...

10-22-12, 08:36 PM
Well, I apologize and stand corrected. I do know the Northstar engine does use some oil, and I know because I had three of them. I also had two previous 3.6 V6 engines, and even with well over 100m miles on both, neither ever used oil. One did need a timing chain replacement at 95m miles; however, prior to this it was NOT using ANY oil;. When I say ANY oil, it is because I never had to add oil between oil changes (5,000 miles between Mobil 1 changes).



Here is what GM says...
Aggressive Driving, High Speed or High RPM Driving
Aggressive driving and/or continuous driving at high speeds/high RPMs will increase oil consumption. Because this may not always be an everyday occurrence, it is hard to determine exactly how much the oil economy will be affected.

A higher rate of oil consumption is normal for vehicles equipped with manual transmissions that are driven aggressively. By "aggressive," we mean operation at high RPM (3,000 RPM to redline), with frequent use of engine braking (using the engine to slow the vehicle). Vehicles that are driven aggressively may consume engine oil at a rate of up to 0.946 L (1 quart) every 805 km (500 mi). This is normal for a vehicle that is driven aggressively. No repair is necessary. This characteristic does, however, require the owner to check the engine oil level at sufficiently frequent intervals, especially when driving aggressively, to assure the oil level remains within the recommended operating range. As the Owner’s Manual recommends, you should check the oil level every time you get fuel.

Maybe I am just too conservative with my driving? If I was using 1 quart in 500 miles, I'd get rid of the car!