If you are thinking of purchasing a GMC Sierra or a Chevrolet Silverado, you’ll have the option to get it with a 2.7 L turbo engine (also referred to as the GM L3B engine). While the thought of a small-displacement turbocharged engine might seem like a weird (but interesting) choice for a large truck, there are some GM 2.7 turbo engine problems that might make you rethink your decision.
Some of the issues with this engine include poor fuel economy, timing belt failure, and head gasket failure. Many owners complain about insufficient power as well.
Despite not living up to all the promises made by GM, the 2.7 L turbo engine ins’t all that bad of an option. Read on to find out why…
What problems does the GM 2.7 turbo engine have?
The fact that the first 3 problems I’m going to discuss aren’t mechanical in nature should tell you everything you need to know about how reliable this engine is. I don’t think I’ve ever written a “car problems” article with so few specific issues. Anyway, let’s just get into it:
Poor fuel economy
The GM 2.7 turbo engine’s lack of fuel efficiency is surprising to many considering it’s small overall displacement. Generally, with both city and highway use, GM promised an average of 23 miles per gallon. It turns out that the best that most owners can eek out of it is 19 mpg.
This poor fuel economy looks even worse when compared to other brands. For example, the Ford F150 2WD Diesel gets 25 miles per gallon. The Lexus RX 450h AWD Hybrid is even better, coming in at 30 miles per gallon.
In my opinion, you might want to think about another engine (or another vehicle entirely) if you plan on putting a lot of miles on it.
One of the most complaints I hear most about the GM 2.7 turbo is low horsepower. Which seems like an odd complaint if I’m being honest, since it’s lower than average horsepower rating is not exactly a secret.
I get the sense that most buyers choose the 2.7 L turbo for the promise of better fuel economy. Once they realize that they can’t achieve the numbers that GM promises, they realize they made a mistake choosing the smaller (less powerful) engine. Hence why you hear so many complaints about it.
The 2.7 L turbo makes 310 horsepower at 5600RPM. Though this may seem like a lot, it isn’t always enough for larger (heavier) full size trucks.
Another common complaint about the 2.7 L turbo engine that I hear quite often is that it isn’t all that easy to find. Which, again, is an odd complaint considering how many owners complain about low power and poor fuel economy.
Basically, the chip shortages brought on by the COVID-19 pandemic have had an impact on the engine’s availability. Despite it’s lower than expected performance, it’s a popular engine choice that GM hasn’t been able to produce enough of.
Timing belt and head gasket issues
Poor fuel economy and low power issues aside, the GM 2.7 L has been proven to be an extremely reliable engine. Maybe that’s why it’s been in such high demand? I’m not really sure. Anyway, according to my research, I’ve only been able to come up with two mechanical problems that seem to have affected a number of owners:
- Timing belt failure
- Head gasket failure
Note that these are not common problems. According to my research, roughly four percent of drivers found a major engine issue with their GM 2.7 turbo engine. That’s not a lot IMHO.
Is the GM 2.7 turbo engine reliable?
Considering that the majority of the problems of the 2.7 L turbo are related to customer dissatisfaction (and not mechanical), I’m fairly confident saying that it’s a very reliable engine. Keep in mind that it’s a mass-produced engine from General Motors (who aren’t exactly known for producing quality stuff), so it’s not going to be perfect.
To put it in better context, I’d feel good recommending a truck to my mother that had this engine. I’d be sure to tell her about the lower than expected fuel economy though. Not doing so would be downright cruel.
How long will a GM 2.7 turbo engine last?
Though it is difficult to say how long the GM 2.7 turbo engine will last, everything that I’m seeing leads me to believe that (on average), it will have a long life with regular maintenance. 200,000 miles should be easy as long as you take good care of it.
Because of the engine’s extra complexity (turbocharger and direct-injection for example), it will require much more care and maintenance than other normally-aspirated engines. Neglecting to maintain a turbo engine will result in a very short engine lifespan.
How do the problems of this engine compare to other engines?
As I’ve already mentioned, writing about the problems with the 2.7 L turbo has been really easy. There simply aren’t that many issues compared to other smaller-displacement truck engines. The fact that there weren’t that many produced (compared to the competition) could have something to do with it, but it’s hard to tell really. Anyway, here is how it stacks up:
- There are about 5 times the number of problems with the Ram EcoDiesel than the GM 2.7 L turbo.
- 3.0 Duramax problems are less severe than the Ram EcoDiesel, but still more significant than the 2.7 L.
- Problems with the Ford 2.7 L EcoBoost are about as mild as the 2.7 L turbo from GM.
- Ford 3.5 L EcoBoost problems are worse than the 2.7 L from both Ford and GM. Bigger isn’t always better!