Should GM Offer The Turbo 2.7L High-Output L3B Engine In The Full-Size SUVs?57
Despite an industry-wide pivot to electric vehicles, internal-combustion engine technology continues to impress. That includes GM’s turbocharged 2.7L High-Output L3B four-cylinder gasoline engine, which can be found in a broad variety of applications, including the Chevy Silverado 1500, GMC Sierra 1500, Cadillac CT4, Chevy Colorado, and GMC Canyon. Notably, the turbo 2.7L I4 L3B is not offered in GM’s full-size SUVs – but maybe it should be.
While some readers out there will no doubt scoff at the idea of a modern, full-size GM SUV running a turbocharged four-banger, the spec sheet starts to bring things into focus. At present, GM’s full-sizers, including models like the Chevy Tahoe, Chevy Suburban, and GMC Yukon, offer three engine options – the naturally aspirated 5.3L V8 L84 gasoline engine, the naturally aspirated 6.2L V8 L87 gasoline engine, and the 3.0L I6 LM2 turbodiesel Duramax engine.
However, when it comes to peak torque numbers, the High-Output L3B nearly matches that of the L87 and LM2, churning out 430 pound-feet as compared to the 460 pound-feet produced by the L87 and LM2. And compared to the L84’s 383 pound-feet of torque, the L3B simply offers more peak twist.
|Engine Type||Turbo 2.7L I4||5.3L V8||6.2L V8||Turbodiesel 3.0L I6|
|Bore x Stroke (in / mm)||3.63 x 4.01 / 92.25 x 102||3.78 x 3.62 / 96 x 92||4.06 x 3.62 / 103.25 x 92||3.30 x 3.54 / 84 x 90|
|Block Material||Cast aluminum||Cast aluminum||Cast aluminum||Cast aluminum|
|Cylinder Head Material||Cast aluminum||Cast aluminum||Cast aluminum||Cast aluminum|
|Valvetrain||DOHC, 4 valves per cylinder, VVT||OHV, 2 valves per cylinder, VVT||OHV, 2 valves per cylinder, VVT||DOHC, 4 valves per cylinder|
|Fuel Delivery||Direct high-pressure injection with AFM||Direct high-pressure injection with DFM||Direct high-pressure injection with DFM||High-pressure common rail direct injection|
|Horsepower (hp / kw @ rpm)||310 / 231 @ 5,600||355 / 265 @ 5,600||420 / 313 @ 5,600||277 / 207 @ 3,750|
|Torque (lb-ft / Nm @ rpm)||430 / 583 @ 3,000||383 / 519 @ 4,100||460 / 623 @ 4,100||460 / 623 @ 1,500|
|Transmission||Hydra-Matic 8-speed automatic||Hydra-Matic 10-speed automatic||Hydra-Matic 10-speed automatic||Hydra-Matic 10-speed automatic|
Interestingly, the L3B also offers peak torque at a lower rpm than the V8 engines, and more power than the diesel six-cylinder as well.
With all that in mind, the High-Output L3B isn’t really that much of a stretch for GM’s full-size SUVs. Of course, it might not be the best option for the more-refined Cadillac Escalade, but for the Chevy Tahoe, Chevy Suburban, and GMC Yukon, it could very well hold its own.
Then we have fuel economy. While we don’t know what sort of returns the L3B would provide in a full-size SUV, we can estimate, and based on the other gasoline engine ratings, the L3B could provide some pretty decent mpg figures. As a cherry on top, the L3B is actually 130 pounds lighter than the atmospheric 5.3L V8 L84.
|Engine||Drivetrain||GMC Sierra 1500||GMC Yukon|
So then, what do you think, dear reader? Should GM offer the turbocharged 2.7L I4 L3B gasoline engine in some of the automaker’s full-size SUV models? Let us know by voting in the poll below, and remember to subscribe to GM Authority for more GM technology news, GM business news, and around-the-clock GM news coverage.
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Actually shocked they are not offered already.
I expect it is coming anyways. The coming numbers will force it.
Already available in the in full size Silverado. Torque is king. With 430 lb/ft. It will no doubt have no problem powering a Tahoe or Yukon. Revise the tune to bump up horsepower to 325- 330. The 2.0 Turbo in my wife’s Buick Regal has made a believer out of me on the smaller displacement Turbo engine.
A Suburban with four cylinders will SIT on the lots and be a laughingstock. Not sure if even heavy discounts would sell it.
Guess it’s perception; a vehicle that size and price needs an engine to match.
Considering they sit on the lots so long for the Silverado. I would say absolutely not.
When the 4T came out in 18 and the lots were full of trucks you could not find a 4T, same answer we are not ordering any 4T,now gm tells them 4T truck or no truck.
You may save a couple of MPG if you puppy it around town, highway no.
I hope gm stays with the great deal of giving a $2000 “discount” for accepting a 4T.
Only if offered in a base L trim with vinyl bench seatingfor 9 and a 7000$ discount as a contractor vehicle. You have also got to understand that the fuel economy will tank as the 2.7 already rides into the turbo while cruising with the lighter Silverado. Fuel economy numbers will be even worse on the suburban. The 5.3 is a better fit for the suburban. I’d like to see the 2.7 on a traverse however. The 9l65 will need upgraded however.
Got to remember that not even ford offered their 2.7 on the expedition. Engines that small were originally designed for fuel economy, and with the ecoboost coming out as being either eco or boost, there’s no advantage when your in a vehicle that’s just boost. There better be a good monitary incentive or people will just pay the extra grand to upgrade to the more capable engine.
The added weight (SUV are tested with weight simulated to near GVW), the part-load advantage of the small engine goes away. The 5.3 is CHEAP for GM to build.
It would be awesome in the Traverse-
I like the idea of an L trim level Suburban. I grew up riding in an all black vinyl second hand former fire chief station wagon. Somehow, I made it even without the DVD, no XM stereo, no power windows, no A/C, no sunroof, no power locks, no driving nannies, no two tone leather, and (shock) rubber floors. And I still think my Dad was a very cool dude.
Holysh.t!!! Really? Hahahaha. Stone knives and bear skins. That was hilarious.
imma say no. imo it would be better in the traverse / blazer
Not sure it can go transverse and I don’t think the drive line can take the torque.
They once made a 6 speed AWD transaxle for the XTS V-Sport that could take the even more powerful 3.6 Turbo. But now everyone wants 8 or 10 gears for bragging rights.
The XT4, 5, & 6 need this engine badly.
The XTS V-sport was limited to 369 lbs-ft – similarly, Ford limited their 3.5 Ecoboost vehicles to 350 lbs-ft in their cars that also used the GM-Ford 6-speed transverse transmission. A beefed up 9T65 probably wouldn’t get the full bore LB3 tune, but would still have a lot more torque than the 3.6L NA motors.
Even if the rating was around #70, it would be completely flat.
Excellent question. So they put the 2.0LTG in the traverse RS, which made a measly 260hp which pales next to the V6, and the 2.7 L3B is actually a stroker engine with a longer stroke, smaller bore. The bore of the LTG is 86mm, the L3B is 92mm. We’re talking about a little less than 2 inches. Also, they fit a 5.3 into the impala SS in 2007, and it’s bore is also 92mm. As for the transmission, the 9T65 was capable of taking the 300ftlbs from the 2.0 turbo. Definitely not the full 430 ftlbs, but with slight modifications, the original 380ftlbs might be possible.
NO! Increase production of the 6.2 V8.
Yes, well said!!! Possibly the LT4 instead of the L87.
I expect the lighter trucks to lose the V8 at some point and may only be 4 or 6 cylinders.
The V8 can easily live in the larger 3/4 and one ton trucks as regulations are easier on them.
This is what a GM engineer stated a while back. I just did not know if those plans were in play. With the new V8 they may be.
It needs to replace every 3.6 application for sure but what what full-size SUVs need more is a hybrid system.
Great idea, Ford has popularized the turbo 4’s and 6’s across their truck lines with great success. I have a 22 Ranger and it smokes my friends Colorado in all categories, this 2.7 engine sounds like a real winner, we all hope it’s reliable.
I noticed the charts do not provide fuel economy. If there are not much MPG savings then I would rather stay with the proven V8s engines.
The L3B should cost a lot less to produce than any V-style engine. Count the sub assemblies: 1 head, 1 exhaust, 4 pistons, and all the associated parts. There is an additional camshaft and the turbo. This engine will package a lot better in a front drive vehicle. I think GM will slot all its EV’s at higher prices than Gas Vehicles, and thrift out the lower priced gas vehicles until they completely go away.
Talk about the “dog” of the lineup. This is a movie we’ve already seen, with GM’s full-sized 1500 pickups.
Instead of investing in something that really matters, such as–oh, I don’t know–a good interior, GM went all-out designing a four-cylinder engine that powers like a V-8, torques like a V-8, and tows like a V-8.
So what’s not to like? Oh, yeah: This whiz-bang turbo four-cylinder engine still feels like a four and sounds like a four. It’s coarse and shrill, in other words. It turns out, moreover, that the same technology that makes this turbo-four such a powerhouse (at least on paper) is somewhat fragile. For that reason, this precious little engine is prone to breaking down as the miles build up.
The crowning insult? It turns out that real-world fuel efficiency–surely the raison d’etre for designing such an exotic little engine in the first place–is no better than that of the V-8s this turbo-four is intended to replace. Purpose: defeated.
For mama to drop off the kids and get groceries in her $80k Tahoe, 90% of owners will never even know what’s under the hood.
GM should Learn from Porsche and their move to 4 banger in the Boxster. Power is good but the truck will sound like a Singer Sewing Machine going down the road . . . . . . . . . . .just sayin.
Boxer 4’s don’t package well. Their flat, but that makes them insanely wide and their still not very short as the manifolds have to stretch to opposite ends of the engine. Boxer 4’s are for lowering the center of gravity, not packing efficiency, lower weight or power.
Porsche is moving back to flat sixes in the 718 lineup. At least in the GTS & GT4 models.
Also, I had 3 Subie STI’s in the past and I sold them all before or after 60,000 miles. I never trusted the turbo charged engine to last much longer without major turbo repair costs. I experienced one turbo issue in one of the STI’s, a 2010 model that had 29,000 miles on it at the time but out of warranty by 4 months. Luckily Subaru picked up the +$4,000 repair charge as an act of good faith. Would you feel confident that gm would do so for a Suburban in a similar situation?
If I had to chose an engine for a Suburban it would be the diesel, and yes I am aware that it would be contrary to my first statement about turbos.
I will NOT be a buyer of this underwhelming vehicle. Another SKU nobody wants.
If they can’t design a good shifting transmission, what good is any motor!!!
NO! NEVER! BAD IDEA! Remember when Traverse offered a 2.0T? It was salesproof!
Very few want this for an engine in the larger vehicles. It’s a deal killer for many in the GM driving public.