new 6.6L gm heavy duty gas engine in 2020

[2018GMC]

Searching the 'net for gm heavy duty gas engine 2020 has lots of speculation about a new 6.6L replacing the 6.0L for 2020 HD trucks.

 

6.6L LXX

400HP

450TQ

Direct Injected

 

GM 10 speed HD (Allison branded GM built Transmission) ?

[2018GMC]

Current

6.0L

360 HP @5400RPM

380 TQ @4200RPM

Port injection

9.7:1 Compression ratio

87 octane. No AFM / DFM

GM 6 Speed Automatic

 

2020 6.6L L8T 

6.6L

401 HP @5200RPM

464 TQ @4000RPM

Direct injection

10.8:1 Compression ratio

87 octane. No AFM / DFM

GM 6 Speed Automatic

[damnthetorpedoes]

Hopefully the reliability of the 6.0 carries over.

[SierraHD17]

Trans is already confirmed by gm to be a 6 speed with the gas engine.

[gearheadesw]

Direct injection, maybe.

AFM, no.

Stop start tech, no.

Looks like I'll be driving my 2017 6 oh for a while....

[SierraHD17]

Rams 6.4 has MDS so it's a safe chance since GM loves AFM (now DFM) if its 6.6L in size it's going to have cylinder shutdown.

[Cowpie]

Per GM Authority website article.....

 

Notably, the L96 is E85/FlexFuel capable and features Variable Valve Timing (VVT) and Sequential Fuel Injection (SFI, otherwise known as port fuel injection). That is to say that it does not have the latest internal combustion engine technologies such as direct injection, Cylinder Deactivation (in either AFM or DFM guise), or a low-friction valvetrain. By comparison, the new 6.6L unit is expected to adopt these technologies.

 

Read more: http://gmauthority.com/blog/2018/10/next-gen-gm-hd-trucks-to-introduce-new-6-6l-v-8-gasoline-engine/#ixzz5bkizFEC2

[Cosmic Charlie]

GM better do this right - lots of competition

 

If it ain't broke don't fix it (with new fangled technology BS)

[Cowpie]

AFM really makes no sense in a HD gas engine.  Given the market share (commercial) that the HD pickups go to, and what they are being used for, I can't see the AFM would kick in enough to offer any appreciable benefit.  Just another thing that can potentially go wrong.

 

The DI thing is probably inevitable, but that is a minor thing that the owner can take steps to mitigate any problems from that.   

 

Now one I am waiting to see.... whether this new engine will have flex fuel capability.  Many government and commercial users of vehicles desire a flex fuel capability.  I have grown rather fond of flex fuel capability myself.  Having a smorgasbord of fuels to choose from  so that I can use the one that offers me the lowest cost per mile is a pretty good thing.   

 

I know it is a fluke right now, but I am getting E85 for $.99 a gallon at a local station while gas is going for $1.79.   My 2015 2500 6.0 averages about 9-10 mpg on the stuff.  For a 2500 6.0 using regular fuel, it would have to average roughly 18 mpg to break even on cost per mile..  Not going to happen.    On highway miles only, on E85 my 2500 averages about 13.8 mpg.  That was from a 2000 mile road trip last August using E85 only.   For a 2500 on regular fuel to meet the cost per mile of mine on E85 for on highway, it would have to average almost 25 mpg on highway.   Again, not going to happen.    And I am quite comfortable in saying that even with new technology, the 6.6 in a 2500 would not be able to touch those numbers either on regular fuel.  That is why I am hoping they keep the flex fuel feature.

[gearheadesw]

So this new engine is to come out here in just months, correct? No nothing on this engine, has anyone seen it, driven it, is it real? It's to come out this summer, to replace an engine that has been dead reliable for a decade, and no one has anything to say about it? What if this engine comes out to be a total dud, how many test miles have been put on this thing? I see a severe embarrassment coming up....

[i82much]

2 hours ago, gearheadesw said:

So this new engine is to come out here in just months, correct? No nothing on this engine, has anyone seen it, driven it, is it real? It's to come out this summer, to replace an engine that has been dead reliable for a decade, and no one has anything to say about it? What if this engine comes out to be a total dud, how many test miles have been put on this thing? I see a severe embarrassment coming up....

i hear ya but i felt the same way when they replaced the 350 and 454 with the LS engines.  i actually bought a 4.3 truck instead of a 4.8 because i was so worried about the ls engine being unproven.

 

in that case, i gave up about 80 horses and some torque for no real reason.  a 4.8 would have lasted as long or longer than the proven v6.

 

i say give it a few years and we will see.  but sometimes, they definitely get it right.  i love my 6.0, but i hope the new gas engine exceeds it in every possible way.

[gearheadesw]

1 hour ago, i82much said:

i hear ya but i felt the same way when they replaced the 350 and 454 with the LS engines.  i actually bought a 4.3 truck instead of a 4.8 because i was so worried about the ls engine being unproven.

 

in that case, i gave up about 80 horses and some torque for no real reason.  a 4.8 would have lasted as long or longer than the proven v6.

 

i say give it a few years and we will see.  but sometimes, they definitely get it right.  i love my 6.0, but i hope the new gas engine exceeds it in every possible way.

I'm trying to stir things up, get someone pissed off enough to tell us what this engine is. Same block as the 6 oh? Bored and stroked, aluminum block, what heads? Direct injection for sure and stop start crap, cylinder deactivation, but that all sucks. This engine is already stacking up to be a disappointment. Replacing the only thing on the truck that is rock solid.

[i82much]

3 hours ago, gearheadesw said:

I'm trying to stir things up, get someone pissed off enough to tell us what this engine is. Same block as the 6 oh? Bored and stroked, aluminum block, what heads? Direct injection for sure and stop start crap, cylinder deactivation, but that all sucks. This engine is already stacking up to be a disappointment. Replacing the only thing on the truck that is rock solid.

6L90, 14 bolt, boxed frame, and 2011 up IFS aren’t rock solid enough for you?  i have more faith in my 6.0 2500HD than I have had in a vehicle for a very long time.

[redwngr]

The only thing carry over on the 2020 25/35 series HD gas engine chev is that they are still calling it a Silverado.

[gearheadesw]

1 hour ago, i82much said:

6L90, 14 bolt, boxed frame, and 2011 up IFS aren’t rock solid enough for you?  i have more faith in my 6.0 2500HD than I have had in a vehicle for a very long time.

Well, that came out wrong, love my truck, dead solid. It seems to me that we had usually heard something of interest within 2 or 3 months of a release of a brand new engine, there's just nothing of the structure of this new block. I guess it's the new thing, just like the new 3 liter diesel that's coming out, nothing concrete about the real running versions that are around.