How reliable is the 6.6 gasser?

[KARNUT]

8 minutes ago, 64BAwagon said:

My son has a 1500 SIlverado with the 2.7L Turbomax. he really doesnt do any towing (not that it wouldnt work well) and he feels the 4 cyl is enough motor for a daily driver, he is pretty happy with it. It had a huge impact on the price of the truck. 

Honestly most of my life what drew me to a V-8 was the exhaust sound. Now that the period has passed and I prefer quiet. As long as it performs I don’t care what’s under the hood.

[64BAwagon]

The 2.7 is definitely not a great sounding engine. 

[Pryme]

13 hours ago, KARNUT said:

Honestly most of my life what drew me to a V-8 was the exhaust sound. Now that the period has passed and I prefer quiet. As long as it performs I don’t care what’s under the hood.

I don’t think I’ll ever tire of the sound of a good ole V8 starting up in the garage on a cold winter day at high idle with that deep rumble as it idles down. 
 

insert Tim the tool man sounds here

[BuckWallace]

I had two 5.7 Tundras before my 2024 L8T. Last week I finally drove one of the new twin-turbo V6 Tundras, and that fake engine noise they pump through the speakers is pretty hilarious (and annoying).

[Dunn]

I am 56yrs old and still love the sound of a V8....dont know ill ever tire of it, it doesnt have to be loud or cray aftermarket system....stock is fine

 

21 Ram laramie had a really nice sound......about only thing I really liked though,lol

 

 

[newdude]

I'd say 4 years in and 95% of the 6.6 HDs we've seen though the shop have been trouble free.  A few with bad oil cooler lines, two for oil consumption which, had leaking oil cooler lines.  

 

We did however just replace one and are working on another.  The first one we just finished, customer had their oil changed just over 80k mi and the shop that changed it said the oil was full of glitter.  It was running rough too.  That one just got picked up, fresh long block.  

 

The other one, the tech is working on the install of the long block.  2021 Express 4500 school bus, I think 43,XXXmi?  I have pictures of that one.  It straight up broke a 1/3 of the valve off, which that then bounced around and the tech actually found it in the intake manifold.  

 

 

 

 

 

 

 

On 5/13/2024 at 9:57 AM, 64BAwagon said:

Rumor has it that the L8T will soon be making its way into certain 1500 series trucks. Since the 6.2 has proven to have numerous issues it will be removed from availability. No idea what trans though. The trans size may limit the HP/TQ numbers in the 1500. 

 

 

Don't see it happening IMO.  Also, L8T makes 20 less HP and only 4 more torque so 10L80 wouldn't have a problem behind it.  

Edited May 19 by newdude

[newdude]

On 5/13/2024 at 11:37 AM, 64BAwagon said:

Thats not what I heard, plus cylinder deactivation isnt going anywhere on that motor (6.2L even though it may get phased out) since GM gets credits from the Govt for using it (which reinforces my long standing opinion that the Govt has more control on what gets built than GM does) 

Apparently the Govt already isnt happy about the 6.6 not having it and have pushed for it on the 6.6. Hopefully it stays the way it is rather than ruining another great gasoline V8 with Govt imposed crap. 

There seems to be a lot going on behind the scenes. 

I cant pin down the changes on the 25 models (I sure hope they fix the lousy dashboard on the Chevy)  even though they have run a couple of pilot runs. There is supposed to be a line changeover in July for the 2025 model and beyond that will halt production for a week or so. 

Sounds like if youre not a fan of change youre going to be disappointed. 

 

 

Changes are already public.  New Features (gmfleetorderguide.com)

 

Nothing to pin down.  Dashes were just changed for 2024 except on low trims, L5P was updated and 10 speed with gas, so don't expect any major changes until the next gen.

 

 

 

Edited May 19 by newdude

[64BAwagon]

10 hours ago, newdude said:

I'd say 4 years in and 95% of the 6.6 HDs we've seen though the shop have been trouble free.  A few with bad oil cooler lines, two for oil consumption which, had leaking oil cooler lines.  

 

We did however just replace one and are working on another.  The first one we just finished, customer had their oil changed just over 80k mi and the shop that changed it said the oil was full of glitter.  It was running rough too.  That one just got picked up, fresh long block.  

 

The other one, the tech is working on the install of the long block.  2021 Express 4500 school bus, I think 43,XXXmi?  I have pictures of that one.  It straight up broke a 1/3 of the valve off, which that then bounced around and the tech actually found it in the intake manifold.  

 

 

 

 

 

 

 

 

 

Don't see it happening IMO.  Also, L8T makes 20 less HP and only 4 more torque so 10L80 wouldn't have a problem behind it.  

I would be willing to bet you lunch that it does. 

 

There are some electrical changes that the customer wont see and something like 700+ part number changes on the 25's I doubt many people will notice. The color and option changes are pretty boilerplate stuff from year to year. 

Edited May 19 by 64BAwagon

[newdude]

On 5/19/2024 at 8:10 AM, 64BAwagon said:

There are some electrical changes that the customer wont see and something like 700+ part number changes on the 25's I doubt many people will notice. The color and option changes are pretty boilerplate stuff from year to year. 

 

 

What proof do you have of these "changes nobody will see" for 2025?  That already happened for 2024.  All of the electrical and under skin changes happened (the move from Global A to Global B aka GM VIP), just like they happened first on the 2022.5 1500s.  2025 HD is the same exact truck as 2024 HD. 

 

Large changes between model years or generations notes a decent size gap in production end and start dates.  The changes present from 2024 to 2025 are those that they could finish 2024 production on July 26th and start it July 29th (which is the 2025 start date).  

Edited May 20 by newdude

[customboss]

On 5/19/2024 at 6:10 AM, 64BAwagon said:

I would be willing to bet you lunch that it does. 

 

There are some electrical changes that the customer wont see and something like 700+ part number changes on the 25's I doubt many people will notice. The color and option changes are pretty boilerplate stuff from year to year. 

Hope you pay for lunch better than Grumpy Bear does, he never returned my favor to him when I drove to Illinois to meet him.    Not evem Spam in a can..... 

 

[ScathaTheWorm]

On 5/13/2024 at 6:37 PM, 64BAwagon said:

Thats not what I heard, plus cylinder deactivation isnt going anywhere on that motor (6.2L even though it may get phased out) since GM gets credits from the Govt for using it (which reinforces my long standing opinion that the Govt has more control on what gets built than GM does) 

Apparently the Govt already isnt happy about the 6.6 not having it and have pushed for it on the 6.6. Hopefully it stays the way it is rather than ruining another great gasoline V8 with Govt imposed crap. 

There seems to be a lot going on behind the scenes. 

I cant pin down the changes on the 25 models (I sure hope they fix the lousy dashboard on the Chevy)  even though they have run a couple of pilot runs. There is supposed to be a line changeover in July for the 2025 model and beyond that will halt production for a week or so. 

Sounds like if youre not a fan of change youre going to be disappointed. 

Ford's Godzilla does not have cylinder deactivation, and has camshaft and lifter problems....

I DOUBT the 6.6 gas will be getting cylinder deactivation anytime soon. MY25 and MY26 will likely be the same. That segment in general is NOT regulated as much as the 1/2 ton segment. 

Also, the EPA and CAFE unfortunately have control over what they build with regards to the 6.2, so complaining about DoD will NOT do anything.

[ScathaTheWorm]

On 5/19/2024 at 4:32 AM, newdude said:

I'd say 4 years in and 95% of the 6.6 HDs we've seen though the shop have been trouble free.  A few with bad oil cooler lines, two for oil consumption which, had leaking oil cooler lines.  

 

We did however just replace one and are working on another.  The first one we just finished, customer had their oil changed just over 80k mi and the shop that changed it said the oil was full of glitter.  It was running rough too.  That one just got picked up, fresh long block.  

 

The other one, the tech is working on the install of the long block.  2021 Express 4500 school bus, I think 43,XXXmi?  I have pictures of that one.  It straight up broke a 1/3 of the valve off, which that then bounced around and the tech actually found it in the intake manifold.  

 

 

 

 

 

 

 

 

 

Don't see it happening IMO.  Also, L8T makes 20 less HP and only 4 more torque so 10L80 wouldn't have a problem behind it.  

Both of those look abused....

This is not as widespread...as lets say, the 7.3 Godzilla camshaft delamination problems (which I am not sure still happens on the MY24s....).

[newdude]

4 minutes ago, ScathaTheWorm said:

Both of those look abused....

This is not as widespread...as lets say, the 7.3 Godzilla camshaft delamination problems (which I am not sure still happens on the MY24s....).

 

 

The first one with 80k I bet was.  The bus with the pictures I posted?  Most of the bus garages we deal with, they have great maintenance records (which were provided), and with the way that valve is broken, to me, it seemed more a metallurgy issue (weak valve casting by the stem area).  It wasn't like an injector stuck and melted the valve, the valve straight up cracked.  

Edited September 3 by newdude

[ScathaTheWorm]

3 hours ago, newdude said:

 

 

The first one with 80k I bet was.  The bus with the pictures I posted?  Most of the bus garages we deal with, they have great maintenance records (which were provided), and with the way that valve is broken, to me, it seemed more a metallurgy issue (weak valve casting by the stem area).  It wasn't like an injector stuck and melted the valve, the valve straight up cracked.  

Then I suspect it might have been defective from the factory....or the person was unlucky.

[64BAwagon]

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.