[XtremeRevolution]

IMO, the 1.4T won't hold up to as much abuse as the GM 3800 could. But properly maintained, the engine itself should be good for 200k+ miles. The turbocharger is my only concern about this engine making it to 200k without any major repair.

The key word is "with proper maintenance."

The GM L67 and L36 required significant work to remain reliable. Regarding the L36, we had a faulty upper intake plenum that required replacing due to the EGR valve causing the plastic to crack around the coolant passages, potentially flooding the engine with coolant, in addition to lower intake manifold gaskets that were in terrible shape well before 200k miles. We had the coolant elbows that liked to crack, an oil pan gasket that was notorious for leaks and required a removal of the subframe to remedy, and very common idler pulley bearing failures. The supercharger added another maintenance item that was very often ignored.

I suspect that, like the 3800 series, the 1.4T will be just as reliable once known issues are remedied. The key to this is proper maintenance and preventive maintenance. It goes without saying that good lubricants that are changed according to their usable service life will go a long way. Going 10,000 miles on DEXOS1 oil in city driving is a sure way to reduce the life of your engine just as going over 90,000 miles on transmission fluid for either engine is sure to reduce the life of your transmission.

The turbocharger is lubricated through the use of scroll bearings and cooled by both the oil and the turbo. So long as a lubricant is used that withstands the heat produced by that turbocharger without shearing, oxidizing, or becoming acidic, the turbo should theoretically last the life of the engine. This would also assume that the antifreeze is maintained to its service life of 150,000 miles or 5 years, whichever comes first. The cooler you can keep the turbo and the better you can keep it lubricated, the longer it will last you.

Mazdaspeed3 owners learned this lesson the hard way when Mazda insisted that they use conventional oil. Turbo failures between 30k and 60k miles were not uncommon. Subaru WRX/STI motors suffered the same fate, only those turbos ran so hot that they oxidized the heck out of the oil, which then caused it to sludge and clog the oil mesh screen inside the oiling system, thus starving the turbo of oil. With turbocharged applications, oil is absolutely critical to the turbo's service life.

That being said, there was one instance of a turbo failure reported where the compressor housing literally cracked. Unfortunately, the best lubrication won't save you from that, but excellent cooling will help prevent it. This is not intended as an AMSOIL plug, but this is one reason why I run the Dominator Coolant Boost, which increases surface tension between the metal and the antifreeze to provide better heat transfer. In theory, this should keep the turbo cooler, which in theory should extend its life.

 

[XtremeRevolution]

Here is a link to my early 250k mile post.

http://www.cruzetalk.com/forum/34-1-4l-turbo/91042-greetings-moon.html

It is worth noting that your driving conditions are especially light and easy given that your driving is 100% highway at relatively calm highway speeds. Your car also experiences far fewer heat cycles as a result of your trip duration than any other outside those driving conditions would.

 

[XtremeRevolution]

While this is true we have a few members at or above 150,000 miles on their 1.4T engines who drive a more typical driving pattern. The biggest concern I've run into over the years is calendar age. Parts dry out with age, regardless of maintenance.

Some of that does have to do with the heat cycles. I'm fairly confident with this motor's long term reliability however. There are far fewer rubber parts than in older cars I've owned.

 

[XtremeRevolution]

Thanks for the comments and insights. One thing this little 1.4 four cylinder turbo has going for it is that it only revs up to 2200 at 70 mph. So that has to be big. My 3.8 litre Impala ran at 2000 at 70.

Yep. My Eco runs 2000RPM at 65mph. Very impressive for a 1.4L four cylinder engine. In addition, the pistons are very low friction using a DLC (diamond-like coating) on the pistons rings that allowed GM to significantly close tolerances. This is also why the engine barely consumes any oil, if not none at all.

 

[XtremeRevolution]

I am currently at 67k and I have had a water pump, and a turbo replaced. I am not confident in the life of the second turbo. I also have the whining manual transmission, so I am hoping by 70k+ I can get it replaced as well. I plan to ditch this cruze at the end of my extended warranty. Fun car , but I don't trust it.

What did you do to require a turbo replacement? Also, what lubricants and at what capacities are you using in the transmission and engine?

 

[XtremeRevolution]

On the first 10k on my cruze i lost a manual transmission. (The bearing whine) On my replacement i didn't mess around and swapped the trans fluid with ams oil. Still runs great. @ 55K miles now.

I blew my second turbo by hitting the track 5 days in a row, by the 5th day i could hear a whine when it was spooled. A week later it failed on my way to work. Stock turbo is amazingly reliable as long as you let it rest between pulls.

Im very confident in the engine *knock on wood* We'll see how it holds up to the bigger turbo.

Ah yeah, that bearing failure. Thank GM for under-filling the transmission. I'll shoot you a PM about the turbo thing though. I have a few ideas.

 

[XtremeRevolution]

The 3800 Series II and III are the best pushrod v6 engine ever made for mass production. I almost dumped buying my Cruze to buy a 2007 Grand Prix with an L32, SC 3800 Series III. GM first made the v6 in 1962, sold it to Jeep and then bought it back. In the late 70's the 231CI or 3.8L became the standard displacement for the v6. Then during the 80's this v6 was put in the Turbo Regals, with the most famous being the Grand National. However, the 109 block(from the Grand National) is nowhere near as good as the 3800 Series II and Series III. The Series II and III blocks are just are strong as Buick Motor Sports racing stage 2 3.8L block made in the 80's. The stage 2 blocks easily crank out 1600HP, as long as it had a stage 2 crank, rods, etc. Buick or GM had a lot of time to refine the 3800 and people are now starting to put the 3800 Series II and III (L67 and L32) in Grand Nationals and T-Types because they are so superior to the LC2. Anyway, comparing the family0 1.4L ecotec to the 3800 Series II and III is an apple to oranges comparison. The Buick v6 3.8L or 3800 had a very long life. From 62 to 08, the family 0 1.4L ecotec has only been out for how long. For the family 1 1.0 to 1.5L ecotec, from I what I have read these blocks should be an improvement over the family 0. For one the turbo engines will get a forged crank, instead of a cast crank. I guess we'll see. It would be nice to get 200k miles out of my Cruze with no major repairs.

In my experience owning two series 2 L67s and one Series 1 3800 L27, I have to admit the L27 was from a reliability standpoint a superior motor. Easier to work on, simpler, and the longer stroke with a taller deck made for some interesting performance gains as the piston spent more time near TDC. I had the intake and heads ported on mine with YT roller rockers and I was doing 94% injector duty cycle on the stock injectors. Blew a roller on a lifter before I ever had the chance to see how much power it actually made unfortunately. The series 2 had the LIM gasket issue, the UIM plenum issue, the coolant elbow issue, and far more evap issues while not feeling all that much faster despite making 35hp more.

I miss that L27.