In addition to announcing the new 3.0-liter twin-turbo 400 horsepower V6 LGW engine today, Cadillac also announced a new naturally-aspired 3.6 V6 to be employed in the CTS, ATS and the yet-to-be-revealed CT6. Assigned production code LGX, the new 3.6-liter motor is part of GM’s fourth-generation DOHC V6 engine family and utilizes cylinder deactivation and stop/start technology in order to deliver enhanced fuel economy over the outgoing 3.6L LFX. After rolling out for Cadillacs, the LGX will likely become available in other GM vehicles — possibly the 2016 Chevrolet Camaro.
The new 3.6-liter LGX engine, which is a clean-sheet design and shares very little with GM’s current 3.6L V6 LFX engine, delivers an SAE certified 335 horsepower and 284 pound-feet of torque. It retains the aluminum deep-skirt cylinder block of the LFX mill, however the bore has been enlarged from 94mm to 95mm and the bore centers have grown from 103mm to 106mm. There’s also an all-new cylinder head design, a forged steel crankshaft, high-strength connecting rods and pistons and oil-spray piston cooling.
The cylinder deactivation and active fuel management systems, all new for the fourth-gen V6 family, contribute to a 9 percent increase in efficiency over the previous engine. Cylinder deactivation powers down the engine’s No. 2 and No. 5 cylinders in light-load driving conditions, while the start/stop system will shut the engine off completely when it’s stopped and automatically turn it back on when the driver lifts their foot off the brake.
Fuel economy is further improved by changing the direct injection and continuously variable valve timing systems. The new-generation V6 LGX features VVT with an ‘intermediate park’ feature, which will automatically set the cam in the optimal position for a cold start, thereby improving fuel economy. The piston tops have also been carefully shaped to promote a better mix of the air and fuel during the direct injection process, ensuring a more “complete” combustion. As a bonus, the LGX runs on regular fuel and does not require premium.
Similar to the twin-turbo 3.0-liter LGW, refinement was at the forefront of GM’s focus for the new 3.6 LGX. The oil pump has been moved underneath the cylinder block and is located inside the oil pan for greater silence, while the engine cover actually serves an acoustic barrier to further reduce noise. The oil pan itself is also made of stamped steel for “optimal noise-absorption characteristics,” according to Cadillac.
The new 3.6-liter V6 LGX engine will be built alongside the new 3.0-liter twin-turbo at GM’s Romulus Powertrain assembly plant just outside of Detroit. The LGX will first debut in the CT6 and will later also become available in the smaller CTS and ATS, as their powertrains receive a refresh.
Comments
Now we all know these engines will be employed across every GM brand, but let’s not forget: Cadillac had it first! I can better see how this strategy can bring honor to Cadillac. As long as there remains some engineering and mechanical differences in each application; this way Cadillac and GM can better preserve some exclusivity.
What Cadillac needs to do, is get these engines in the CTS and ATS as soon as possible, in order to gain an advantage on its competitors. In that way, sales should definitely go up. Hence, with these new engines and the 8-speed transmission, I think that Cadillac should gain the upper hand on the competition in performance and EPA numbers department.
You are correct that the 2015 ATS 3.6/6 speed was the weak link – especially compared to BMW 3.0T/8 ZF and this should put them on par with (not above) competitors. Unfortunately Cadillac is making a very good product (ATS/CTS) that people just are not buying due to the poor perception of the brand (for old people) and the weak dealer network and older facilities compared to many competitors. I live in NJ where there are Audis, BMW’s, Mercedes, Infiniti, Lexus in every driveway – and not a single Cadillac. I am ordering a 2016 ATS Performance 3.6 AWD as soon as possible in July – and get a look of disbelief from most people I tell…perception is their reality.
With these new updates for ’16, it makes the excellent ATS and CTS more excellent. A good time to be a Cadillac enthusiast.
Cadillac have 2.0 turbo, 3.0 turbo and 3.6 turbo. I’m struggling to see the need for this N/A 3.6.
3.6 in Limo’s and hearses no turbo needed in a funeral. Few people are in that much off a hurry at that point.
There will be a need but not for the average buyer.
More powerful ,smoother ,quieter,more effecient and uses regular gas. Seems like a win win situation to me. Beside if the normal aspirated is more powerful and effecient it stands the reason the turbo versons will be too.
Great job, GM! Keep the momentum going.
There is still a huge need for the 3.6NA engine. The 2.0T is 295HP. The 3.0TT is 400HP. The 3.6TT has up to 455HP.
There needs to be an intermediate engine between the 2.0 and the 3.0TT. It now takes regular gas with higher power density as well.
Still fits in the same position it currently does; top non-V engine for ATS. Mid-range engine for XTS. Base motor on XTS. Top engine on SRX (for now ). Base motor on CT6.
I’ll echo the sentiments of many on here that I like where GM is headed here with new model and powertrain offerings. You can kind of see what they are trying to do.
So will cylinders 2 and 5 start to gunk up first with carbon? Can’t wait to see that!!!
Why would they “gunk up first with carbon”? They will not be getting any fuel when they are deactivated so where would the carbon come from?
I agree that there needs to be an intermediate engine but I’m surprised they redid the NA 3.6. Every lux car has switched or is switching to forced induction even infiniti will be ditching their 3.7 next year for a 3.0TT. I think it would have made more sense to replace the 3.6 NA witch the 3.0TT especially since the Vsport engine they just introduced last year has about the same output figures as the new 3.0. seems like a waste of money and time, plus no one want NA engines anymore.
Who says no one wants a NA engine anymore? 335 HP is a nice step up from 295 and they could use the 3.0 TT as a V Sport in the ATS. What they need to do is get rid of the 2.5 NA in the ATS and go with a low pressure 2.0 Turbo with about 250HP. That would give the ATS a nice choice of engines and a more competitive standard engine.
There’s a reason every lux brand is moving away from NA , a turbo engine is more flexible and has a broader torque curve then NA engines. Just a waste of resources to develope this when they could just detune the 3.0tt to 335 hp and way more torque then the 3.6. Agreed that they should to get rid of the 2.5 in the ATS. Also a AWD Vsport CTS for us in the north east while they’re at it.
I agree with you 100%. I remember an automotive engineer saying “horse power sells cars, torque wins races” I really don’t see the need to develop a new N/A V6, when they have two TT V6s available. With tuning, they can have any power they want, from 300hp, all the way up to 450hp and a broad torque curve that is just absent in N/A
You sometimes think that people who have never actually been on a track are the people saying ‘no one wants NA engines anymore’.
The people who tend to buy manuals despite them having slightly slower 0-60 times are the same people who value a car’s fun factor. NA engines in general have more linear throttle response, don’t die at the top of the rev range, exhibit no lag, almost always sound better and are easier to develop to run on regular gas.
Although turbo lag has been reduced these days, even BMW’s 335i does exhibit lag once they switched from a bit turbo to a twin scroll turbo. Some of us value the experience over pure performance numbers.
Agree with the 2.5NA but the 3.6NA is still the volume engine and runs on regular gas.
The new 3.6TT would make a great ATS V-Sport engine. I wouldn’t be surprised if that was already in the plans.
Replace the 2.5NA with a modified version of the new 1.6T engine with a bump in power and refinement.
Although I do not see larger displacement NA engines down the road, I can still see a need for this one.
They already have the 3.6 TT in the ATS V alllthough it has a higher HP rating than the 3.6 in the CTS V sport. I still think the 3.0 TT would be a better fit for the ATS V sport.
I meant 3.0TT for a potential ATS V-SPORT model. My bad.
The ATS is a luxury, sports car, I don’t see the sense in having any engine smaller than the 2.0T. That 2.0T will be the base engine. With GM using a TT 3.6 for the ATS-V the ATS-V sport will get the 3.0T, tune to about 100hp less that the ATS V. The NA 2.5 will be dropped.
So then this was on the Avenir then?
355HP on the 3.0TT in the ATS-V is not enough of a gap compared to the 3.6NA engine at 335HP to be worthwhile.
The gap in HP in the CT6 to the CT6 V-Sport will be 90HP so for the ATS it would seem that keep the 3.0TT at it’s current power figures (400HP ) makes sense.
I hope there will be a setting to allow the customer to override/bypass the stop-start feature.
Why bypass the start /stop feature?
Detuning a larger displacement engine is pointless; especially when they can get better fuel economy and power delivery out of a slightly smaller engine with a higher boost. I’m sure we’ll see either a new I4 for Cadillac. Hopefully a new 1.8t with 265HP and 280LB-FT as the base engine in the ATS. As for the LGX 3.6L V6, these improvements will help it become more responsive and efficient than the LTG 2.0t I4. I have heard many rumors that GM is working on a new 2.7t V6 which should have around 340HP and 350LB-FT. In the future, it will be likely to see a 1.6t I4 with 205HP and 220LB-FT in the sub-ATS sedan.
Will this engine swap out with my 2013 ATS with the 8 speed as well. It will cost less than a whole new car??