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Lots of misinformation being reported. The 3.6 is the worst engine GM made. LOL really! Because of a bad timing chain! I have an 2013 Impala with the LFX and closing in on 40K miles with zero issues. I have seen and know loads of people with 2012 onward LFX Impalas and Camaro's and none have reported any issues with the engines, even ones with 100K miles. Before people spout off that the 3.6 is a bad engine they need to do some fact checking.

For starters there are different versions of the Global high feature 3.6 dating back to 2004 on the Cadillac CTS. This was the LY7. This was followed in 2005 by a 2.8 version of this engine named LP1 and then an LP9 turbo used for Saab and in LAU guise as the upgrade motor used in the 2010 SRX. Then there was the LF1 and LFW 3.0 liter SIDI V6 with integrated exhaust manifolds and E85 capable. Then there was the LLT version of the 3.6 which upgraded to the 3.0 liter engines SIDI system but still used separate exhaust manifolds. This was unveiled in 2006. The LFX version of this engine debuted in 2012 on the Camaro and Impala it was 20 LBS lighter than the LLT, used the 3 liter's integrated exhaust manifolds, composite intake and timing chains from a different supplier along with altered or sooner oil change intervals.
Also offered are the LF3 and LF4 3.6 twin turbo engines with 410 and 420 HP outputs and currently the latest iteration of this mill is the LGX which is being introduced on the 2016 Camaro and 3 Cadillac models, the ATS, CTS and the new CT6. Also a new 3 liter twin turbo 400 HP V6 is being introduced on the CT6 sedan but I don't know the code for that engine yet.
It's also been noted that timing chain issues are reported in much greater frequency on the LLT 3.6's in the Lambdas and earlier iterations of this engine. On the earlier engines some of the problems stemmed from a cam position sensor that was overly sensitive and was tripping the CEL light too often and soon. This was one campaign recall. The other involved faulty chains from a supplier and that was rectified with a new supplier and a shorter oil change interval. It was also proven that use of dino oil that didn't meet the new Dexos standard and prolonged change intervals was causing chain stretch on the older supplied chains. Note that there are actually 3 chains in these motors, one for each head and one primary chain that connects them to the crank. There are special tools need to change these including a cam holding plate. Most GM techs have done numerous examples and have these down fairly well. The newest 3.6 I have heard with an issue has been on 2012 LLT engines in the Lambdas. No issues reported yet with LFX or 2013 newer engines.
 
No not necessarily - and or not at all.

An OEM can have an OLM set up correctly including 'their' definition of margins, and the service industry / customer base can blow right past that - using wrong spec and or poorly constructed oils and or filters especially if many / most other factors such as interval are ridden hard and or exceeded.

Of course as also fully expected, substandard fuel / fueling practices can then exacerbate all this - especially on a gasser DI......with lots of say as an example short trip driving...... in a cooler / colder clime.

An OEM can also take retroactive steps to reduce just how much a customer can hurt themselves..... or the 'service industry'.....

Part ( not going to cover it all ) of the service industry / customer fail here was using oil constructed with typically older tech add packs that the newer timing 'silent timing chain system' then literally physically tears apart or at least heavily damages time after time ie cuts up the VIIs.

These now ( eventually as in shortly ) far worse than useless remains ( in every way possible ) are often rightfully considered the ideal sludge precursor material / molecules.

And don't forget as they are heavily damaged / destroyed, the very purpose they are there for also goes out the window ie the oil loses much or all of the functional aspects of the VII and basically reverts to a ****ty version of the base stock.... thus adding another family of fail to the tale of woe.

None of this part of the story is on GM - at all.

There were some specific, smallish runs of production that had shall we say beside some of the...... 'bad chains' one or two other production / design shorts - and that's taking as hard a line interpretively as possible against GM which definitely is not fully warranted.

Besides all the other copious and big majority by effect...... and also frequency service industry / customer fails - 'this' ( below ) is the other factor with real weight.

Specifically this change meant cheating with cheap ****ty old spec oil with old spec add packs was not going to fly anymore. Ditto with regard to crappy fueling.

And all this in turn does not cover all the oil fails possibly involved on a case by case basis.

Smaller Pitch Timing Chain

The 3.6L V6 VVT in the Cadillac CTS has a new timing chain with a smaller pitch (7.7 mm compared to 9.5mm previously) and more links. The chain features an inverted tooth design. The smaller links engage at a lower impact speed, which decreases the noise generated. In conjunction with the new chain, the number of teeth on the sprockets is also increased, increasing the meshing frequency and further reducing noise and vibration.

The new timing chain is a running change that will occur in all of GM Powertain’s V6 VVT engines through the course of the 2007 model year. -

All old hat.... for a student of the How Not to Design and Build A V6 / I4 / V8 'Chapter 35' ( mid late '90s ) as authored by the unchallenged expert in the field ie Toyota.

All the above btw, assumes correct viscosity which is beyond ludricious and also can bring yet again another type of oiling fail.
 
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My wife had a 2012 Impala with the 3.6L V6. We bought it because it was a lot of car for the money and performed very well. The interesting thing is my wife got better mileage with the Impala than her current Malibu with the 2.5L. She drives the same mostly city driving as she did with the Impala but the Malibu only averages around 20 MPG while the Impala 3.6L averaged around 23 or so.

She really liked the Impala for 33,xxx miles until the check engine light went on and went into "limp" mode. She had it towed from work and the dealer replaced the timing chains. It didn't cost us a dime, but after that my wife said she couldn't rely on it and we traded it on the Malibu. It was a mistake as she has never liked the Malibu as much.
 
Traverse/Acadia still have the older LLT 3.6. Though I do have 96k on our '10 Traverse with no timing chain issues. I believe the Equinox/Terrain have the newer LFX.

And your Equinox had the 2.4, not the 2.5.
This problem started to appear in the first generation of this motor the LY7 which I have in my 2004 SRX, I have been concerned about the Timing chain since I bought the car after reading article's about the timing chain problems. Luckily I have been one of the lucky ones and now have over 220,000 on the clock and still ticking. I do keep a close eye on the oil though and change it with Mobile one earlier then required. There was some sludge in her when I bought her but after a couple of oil changes it has disappeared. I have owned her for 5 years and put over 110,000 on her. She has treated me good so I take good care of her.
 
Add another one to the list. Timing chain failure at just over 54k. Saturn Aura XR with the 3.6L engine. I used the OLM. Never again.

For me it most definitely was a safety issue as the engine lost power in the middle of a busy intersection.
 
How often did it tell you to change the oil and at what point did you change it?
I thought GM shortened the oil change intervals programmed into the OLM at the same time they opened up the CAM to CAM and CAM to crank timing tolerances. I believe these software changes were what pushed most of the timing chain issues to post warranty period. (that and shortening the warranty period)
 
Hi,

Ive got the LF1 motor in my Equinox, which is in the same engine family. Ive got ~80K miles, and have done full synthetic dexos approved oil changes every 5k miles (OLM around 20-30%) and can report to today that the CEL is on due to a stretched timing chain!

Only difference is instead of offering an extended warranty on a cheap part, GM customer service told me I am out of luck and about $4000. Thanks GM.
 
I agree with many of the folks on this thread. If possible get rid of your 3.6 engine before the warranty is up. I had 118.000 trouble free miles on my 2012 Impala. I was expecting 250.000 miles. After looking inside the engine myself . I have become a firm believer they are a time bomb after 100K. There is a reason as of the 2016s the warranty has been dropped to 60K. Get it together GM, train your shops on how to fix problems or share your info with shops that a capable of taking care of the many issues on these engines. I still have 2 left under warranty then I'm gone. I have time to research other brands. There has got to be a better product. Your Direct Injection is not the answer.
 
This is STILL an issue?:confused: Like 3.8 gaskets for a decade or more?

GM is just asking for a VW-class scandal.

Why should a customer be loyal to--or even shop at--a company that lets known FUBARs go uncorrected?
 
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This is STILL an issue?:confused: Like 3.8 gaskets for a decade or more?

GM is just asking for a VW-class scandal.

Why should a customer be loyal to--or even shop at--a company that lets known FUBARs go uncorrected?
Good point, and it wasn't just the 3.8L, it spread to the 3.4L, 5.0L, 5.7L, 6.0L. And so on. Without any corrective measures. I recall changing the Intake Gaskets in my 5.0L in my driveway. It took the better part of my weekend and the New $145 Gasket was the same as the failed 1 that I took out.
 
Good point, and it wasn't just the 3.8L, it spread to the 3.4L, 5.0L, 5.7L, 6.0L. And so on. Without any corrective measures. I recall changing the Intake Gaskets in my 5.0L in my driveway. It took the better part of my weekend and the New $145 Gasket was the same as the failed 1 that I took out.
And 4.3. Had to do them on a 2003 Blazer over one Thanksgiving weekend. Spurred me to ditch it with only 38K on the clock. At least in that case the new gaskets were of a different design and much thicker than the old.
 
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