How reliable is the 6.6 gasser?

lineman1234 · September 8

15 hours ago, 64BAwagon said:

Buckle up. I am hearing that the L8T is under the microscope and that the focus is on EGR. Its no secret that emissions are going to get stricter in the 2027 MY and that usually isnt a good thing for us consumers.

The new Dmax included.

Doesn't the diesel already use egr?

I had a 2015 cummins 6.7 that had egr, and a friend that has a 2015 duramax with egr. His went bad, or some part on it, they wanted to take the cab off to fix/replace the part, he found another dealer that could do it without taking the cab off, but still it was a $4,000 job.

64BAwagon · September 8

They all use EGR to some degree, the diesels have since the LLY was introduced in 2005. The ones on the gas engines were minimal but my understanding of the change will be that its going to get much bigger and more complex, never a good thing for consumers

Edited September 8 by 64BAwagon

64BAwagon · September 10

I just heard that the new 6.6L gas for the 2027 HD will be designated "L8S"

newdude · September 10

On 9/7/2024 at 5:54 PM, 64BAwagon said:

Buckle up. I am hearing that the L8T is under the microscope and that the focus is on EGR. Its no secret that emissions are going to get stricter in the 2027 MY and that usually isnt a good thing for us consumers.

The new Dmax included.

Interesting. GM did away with EGR on the V8s back oh...2002 was the last year? They've been having good luck since then.

Ram has had EGR on the 6.4 HD truck engine I "think" since it came out. The local Ram dealer does quite a bit of service to the EGR on them too, mostly the fleet trucks that sit idling all day long for the utility companies. Plug up real bad.

C/K Man · September 10

A lot of engines like the L96 and L8T actually do have 'EGR', they just do nor have an EGR valve. Many engines use VVT for EGR, they open the intake valve before the piston hits TDC on the exhaust stroke. This blows some exhaust up unto the intake port, which is drawn back into the cylinder during the intake stroke. This VVT EGR effect also contributes to residue in the intake ports on DI engines as there is no fuel spray to wash it off. It also the reason you usually only see the intake deposits in the ports of DI engines right around and valve, the exhaust doesn't get much of a chance to get and further up the port. There is also a condensing effect as the exhaust is actually hotter than the valve so deposits tend to stick to the port side of the intake valve. High quality gasoline really helps to keep the intake port and valve clean, even on DI engines.

Speaking of Ford's 'Godzilla' 7.3L, I suspect it will gain DI sooner rather than later. I am also hearing Ford finally figured out the cam/lifter issues with that engine. Seems the variable displacement oil pump was allowing oil pressure to get too low during idle. Ford is fixing it with a re-flash.

So the next gen. L8T will become the L8S. Very interesting, that would indicate we will likely see some major changes. I'd like to see them stroke it a bit to get the displacement up, but I think that would require going to a high deck block which I doubt will happen. I wonder if we will see a renewed interest in E85. Since the L8T came out the E85 option has only been sporadically available on certain configurations and trims. No doubt there will be some changes to meet new emission regulations, but I think GM will do their best to keep the engine competitive.

Edited September 10 by C/K Man

C/K Man · September 12

I wonder if L8S be based on the upcoming Gen. VI LS/LT design.

ScathaTheWorm · September 12

On 9/10/2024 at 7:38 PM, C/K Man said:

A lot of engines like the L96 and L8T actually do have 'EGR', they just do nor have an EGR valve. Many engines use VVT for EGR, they open the intake valve before the piston hits TDC on the exhaust stroke. This blows some exhaust up unto the intake port, which is drawn back into the cylinder during the intake stroke. This VVT EGR effect also contributes to residue in the intake ports on DI engines as there is no fuel spray to wash it off. It also the reason you usually only see the intake deposits in the ports of DI engines right around and valve, the exhaust doesn't get much of a chance to get and further up the port. There is also a condensing effect as the exhaust is actually hotter than the valve so deposits tend to stick to the port side of the intake valve. High quality gasoline really helps to keep the intake port and valve clean, even on DI engines.

Speaking of Ford's 'Godzilla' 7.3L, I suspect it will gain DI sooner rather than later. I am also hearing Ford finally figured out the cam/lifter issues with that engine. Seems the variable displacement oil pump was allowing oil pressure to get too low during idle. Ford is fixing it with a re-flash.

So the next gen. L8T will become the L8S. Very interesting, that would indicate we will likely see some major changes. I'd like to see them stroke it a bit to get the displacement up, but I think that would require going to a high deck block which I doubt will happen. I wonder if we will see a renewed interest in E85. Since the L8T came out the E85 option has only been sporadically available on certain configurations and trims. No doubt there will be some changes to meet new emission regulations, but I think GM will do their best to keep the engine competitive.

I heard one report of an MY24 7.3 gas which had knocking and ticking noises...

What will the L8S have? MDS like the 6.4? If that is the case, even the 7.3 Godzilla and the 6.8 will probably follow soon after...

64BAwagon · September 12

The L8S is rumored to be getting an aggressive EGR system that will require a cooler.

I understand that GM was trying to appease the Govt and still avoid the MDS/AFM whatever you want to call it.

The 8.3 Dmax will have different tech than the L5P for emissions purposes.

Pryme · September 12

1 hour ago, 64BAwagon said:

The L8S is rumored to be getting an aggressive EGR system that will require a cooler.

I understand that GM was trying to appease the Govt and still avoid the MDS/AFM whatever you want to call it.

The 8.3 Dmax will have different tech than the L5P for emissions purposes.

Here I’ll say it in layman’s terms. The good ole days of reliable, easy to self maintain trucks is over and pretty much has been for awhile.

64BAwagon · September 12

People have no idea how heavy the hand of the Government is in industry these days. Bureaucrats and reliable, affordable goods are definitely mutually exclusive. Try and buy a "good" appliance or lawn equipment, they dont exist.

Pryme · September 12

30 minutes ago, 64BAwagon said:

People have no idea how heavy the hand of the Government is in industry these days. Bureaucrats and reliable, affordable goods are definitely mutually exclusive. Try and buy a "good" appliance or lawn equipment, they dont exist.

Appliances all suck but I have speed queen washer and dryers and they are still pretty robust and basic. And my Ariens snow blower is still built well.

but yeah you have to search high and low.

lineman1234 · September 13

If people are going to speculate and spread rumors.......

Why not be positive about it and speculate/i heard that the L8T will get more torque with the same fuel usage and the diesel will no longer have an EGR.

Carry on............................

NaturallyAspirated · October 6

Old thread but thought I’d post my 2 cents. Have over 50K mi on my 2 yr old truck. Only issues have been, power steering pump whine (fixed with a flush out plus additive), key gets stuck intermittently (improved but not eliminated with spray lube), and also truck started running a little rough to my sensitive ear at about 30 K mi so I started using Red Line fuel cleaner and decreased oil change interval to <4K mi with M1 (runs smooth all the time now).