GM's 2.7L - Deep Dive

I think the 2.7 in the Cadillac is using the older/original 2.7. This new version in the Colorado came out in 2022 for the Silverado and is now at 420 lb/ft of torque. There are also physical differences between the two versions, some strengthening of the block.
Cadillac owners will never know the difference. All they do is get up early so they can drive around in two cylinder mode and make everyone late for work.
 
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Lead engineer discussing the 2.7L engine. Looks like a really good engine. It's been in the full size for 5 years now. Lot diesel type technology. They put an iron ring carrier on the pistons for higher pressures and a relief valve on the chain tensioner. He goes into some detail in this video.



Long stroke 4 cylinder reliant on a balance shaft that has already posed issues in service, 2 piece sliding camshaft, no port injectors, owners complaining of poor real world fuel mileage.

I wouldn't touch this thing with a 10 foot pole personally.
 
The Vega engine problems manifested themselves in production soon enough that it had a bad reputation within 3 years. The 2.7L has been in production for 5 years, so it's basically a good engine. The Vega was gone by '77 anyhow, why do people want to keep bringing it up?
People still bring up the Vega because we remember their poor reputation. Yet somehow, 40 years later, GM still makes vehicles notorious for burning oil and rapid rusting, like my wife's 2013 Veganox. Oops, "Equinox".
 
People still bring up the Vega because we remember their poor reputation. Yet somehow, 40 years later, GM still makes vehicles notorious for burning oil and rapid rusting, like my wife's 2013 Veganox. Oops, "Equinox".
They used to say on a quiet night you could hear Chev trucks rust.
 
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Long stroke 4 cylinder reliant on a balance shaft that has already posed issues in service, 2 piece sliding camshaft, no port injectors, owners complaining of poor real world fuel mileage.

I wouldn't touch this thing with a 10 foot pole personally.
How about with an 11-foot pole?
 
Long stroke 4 cylinder reliant on a balance shaft that has already posed issues in service, 2 piece sliding camshaft, no port injectors, owners complaining of poor real world fuel mileage.

I wouldn't touch this thing with a 10 foot pole personally.
Google (any popular brand/country) +balance shaft - many companies use them - cars, trucks, tractors, lawn mowers, etc-etc have them …
 
Google (any popular brand/country) +balance shaft - many companies use them - cars, trucks, tractors, lawn mowers, etc-etc have them …
It was Mitsubishi, whose IMO cars are even worse than GM(partly why Hyundai still can’t shake off their junk reputation with some, and the bitter taste of K-Cars/Chrysler minivans with Mitsu engines as well as the Plymouth Colts still linger with some) that invented the counter-rotating balance shaft to make I4/I3s more pleasant. It’s nothing new, GM uses them on the 3.8L Buick V6 and the 4.3L V6 truck V6 due to the fact they are based off 90 degree V8s and aren’t naturally “balanced”.
 
It is hard to trust GM with AFM or DFM. This engine bit complicated. Turbos are hit or miss on top with DFM. Have to wait few years on their new high output engine to see how they do in the real world. If they do well in the next two three years, it will be my next truck.
 
People still bring up the Vega because we remember their poor reputation. Yet somehow, 40 years later, GM still makes vehicles notorious for burning oil and rapid rusting, like my wife's 2013 Veganox. Oops, "Equinox".
GM the Heart Break of America!
 
Google (any popular brand/country) +balance shaft - many companies use them - cars, trucks, tractors, lawn mowers, etc-etc have them …

So what? This engine has TSBs out relating balance shaft concerns/howling.
 
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The race to the bottom continues.

GM = Terrible
Ford = Terrible
Jeep/RAM/Dodge = Terrible
Totoya = Let's see how that 3.4L TT holds up but they have their issues
Honda = Has had issues
Kia/Hyundai = Do I need to say more?
Subaru = Issues
Volvo = Issues
Etc
Etc
Etc

You get my point. No one is making awesome vehicles across their entire range of models these days. Some can't make ANY good vehicles because they all share fundamentally flawed engines or transmissions. The goal seems to simply make vehicles that are "good enough" to get through warranty and many companies can't even figure that out. We as consumers assume these companies are attempting to make the best vehicle they can, which is true to a point, but you have to factor in cost controls and accountants. Once they get involved it's all downhill across all brands. Auto companies are trying to give you their best within a strict/restrictive budget and that seems to mean vehicles that aren't very good. I think technology has been terrible for vehicles because it's complicated and breaks frequently and it eats into the budget for more mission-critical items like drivetrains.
 
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Vega {engine} refers to an undeveloped engine rushed to market where it failed horribly.

I wish this new engine well. I hope there is no hidden flaw.

Using Vega engine as a metaphor makes perfect sense.
It, too, had millions of miles of testing. As did the Mopar 2.7 V6. Northstar. Ford 3.8 V6. Same thing with Dex-Cool. Neon head gaskets. Ford 3 valve truck engines. Power Shift tranny. All dutifully tested.

In 76 GM went back and 'fixed' the Vega engine with improvements that should have been in place by 1972.

Intense short term high miles testing under extreme short term conditions [cold, heat] seems to give just one sort of profile for the engineers. The one they want. In the hands of customers and under real world conditions, results may vary.

Best laid plans and all that.

As always, give it a few years in service first.
 
Google (any popular brand/country) +balance shaft - many companies use them - cars, trucks, tractors, lawn mowers, etc-etc have them …
'balance shaft that has already posed issues in service,'
GM obviously not getting them right is the point.
 
Looking at this engine Silverado or Colorado in 1-2 yrs. Since the V8s are more desirable, these usually end up on the lot and I'll wait till they start dealing again with 8-9k off sticker on the Silverado. Specs are impressive, and I already have a 6.2l.
The trucks have gone up $ 12,000. to $15,000 in the last three years. $9,000 off won't move the needle much.
 
'balance shaft that has already posed issues in service,'
GM obviously not getting them right is the point.
Why are you repeating what he just posted

The word “rely” was what my comment was about - many engines rely on them
 
Also, I am glad to see GM return to a conventional "spin on" oil filter vs. a cartridge style. Lastly, water cooling the turbo should add a lot to longevity. Chrysler found this out in the 80's and 90's when they went to that design.

Yuck...I much prefer the cartridge style - so easy to inspect the pleats for debris and health of engine. Also, less impact to the environment.
 
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