3.0 Duramax

[Dean E]

I got into a bit of a back and forth with this guy on his Youtube channel that I thought I would share with people here. I have been in aircraft and vehicle maintenance all my life, most of that as a field tech rep for a major aircraft manufacturer. Durance and reliability is everything to me. I personally had high hope for the new 3.0 Duramax. If I ever had to replace my trusted LMM this might be a way for me to go. When the engine first came out I was shocked to see they put a wet belt in the back of the engine to drive the oil pump. This pump belt has a life limit to it. What?! This is a brand new from the ground up new engine design. This Youtube guy has interviewed the chief engineer on this engine a few times. The first interview he basically stated that "it is what it is'" and moved on. On the attached link at about the 19 minute mark the guy on the video states that the engineer stated that the reason they went to the belt was because of reaching a minimal noise level that would be noticed in the interior. OK, now I will throw the BS flag on this. You already have chain drives for the cams in the back of the engine, you could not have driven the oil pump with a chain? Yes straight gears will make noise but most beveled gears make very little noise. Practically few engines have induced a life limit on a component with the oil pump, it makes no sense to do one now on a clean sheet designed engine, let alone one that requires the transmission to be removed to access it.

I understand that most owners who purchase this engine new likely will never see the life limit of this belt. The original limit was 150,000 miles. The newer 3.0 has it now at 200,000 miles or 15 years. I go back to my original statement, why induce a maintenance action where none had been required before? If this was to correct an issue on a existing design is one thing. To make it this way on a clean sheet design is another. I hold onto vehicles a long time. I purchased my LMM in 2009 and currently have 215,000 miles on it. I have incorporated a number of mods that will increase the reliability of that diesel engine. It is exceptionally clean and in peak running order and I plan to keep it that way. As long as I don't get into a wreck it could easily be my last truck. It does not even see salt since I used my wife's old Subaru as a work car these days. I know a number of owners of this engine are very happy with it, it does get great mileage but it will not be for me. I also think they made the cooling system way to complicated for what it needs to be. Just my honest opinion. Dean

Source: https://www.youtube.com/watch?v=vx-thbPvxvw&t=1229s

 

[2004LB7]

In case anyone hasn't see the belt/chain setup on these engines. A belt turning a chain turning another chain

 

[Mikey52]

For some reason picture is showing broken link.

 

[Dean E]

Yeah, it can be a real head scratcher wondering what they were thinking! I do seem to remember there are some applications overseas where the engine is turned around where you can access all this from the front. I have already heard of some issues of the chain stretching to where you get valve timing faults. There videos of those and most times they pull the cab off to make it easier to access everything from the back.

It is a good running engine and gets great MPG but it does not look like is will ever come close to our beloved 6.6 for durability. Dean

 

[TheBac]

So why not design a chain/gear setup to replace the belt?

 

[2004LB7]

I wonder how hard it would be to do a gear conversation

 

[Dean E]

I wonder how hard it would be to do a gear conversation

View attachment 128092

Interesting idea but it would require a separate idler gear to keep everything spinning in the right direction. That gear setup in the pic looks like it would howl like a cam gear drive on an old Chevy 350! I would think a chain drive for the oil pump would be more doable if there would be a simple way to mount a tensioner. Dean

 

[Dean E]

I know it is all about economy and getting the engine to warm up quicker but things worked pretty well with the old mechanical thermostat. Engineers love using all this plastic junk in the coolant system. Dean

Source: https://www.youtube.com/watch?v=J0Czns2LtgA

 

[NC-smokinlmm]

I think someone needs to design a chain drive to replace the belt. Then the maintenance interval can be pushed way further out.

 

[kidturbo]

There's 20 years of history behind this Wet Belt bad idea. Someone just improved the rubber compound, thus claiming they'd solved it. Gullible young engineers see it as the Fix All solution.

Park one straight off the showroom for 20 year, then fire it up and let me know how many miles ya actually get before it snaps.. Oil, Rubber, and Time doesn't mix well. End of story...

 

[TheBac]

Is there a tensioner for that belt? I didnt see one on any pictures of the rear of the LM2.
Or bc its a cogged belt it doesnt need one? That would be a bonus if so.

Looks like the crank sprocket for the belt is pressed on, yet the oil pump sprocket is bolted on?
I cant see why an engineer/creative mind cant come up with a chain-driven solution.
CNC both gears and find a mfg for the chain length needed. Install like an old school timing set and away you go.

Or am I really out in left field on this one?

 

[Bdsankey]

Is there a tensioner for that belt? I didnt see one on any pictures of the rear of the LM2.
Or bc its a cogged belt it doesnt need one? That would be a bonus if so.

Looks like the crank sprocket for the belt is pressed on, yet the oil pump sprocket is bolted on?
I cant see why an engineer/creative mind cant come up with a chain-driven solution.
CNC both gears and find a mfg for the chain length needed. Install like an old school timing set and away you go.

Or am I really out in left field on this one?

I think you're spot on personally. It wouldn't be hard at all to do.

 

[2004LB7]

But, but.. it won't be quiet....

 

[Bdsankey]

But, but.. it won't be quiet....

Turn the tunes to 11..................... it'll be quiet then.

 

[1FastBrick]

But, but.. it won't be quiet....

I am pretty sure they still install some sort of radio in these vehicles...

Personally, I think the Welt belts are a cop out.

Ford has the same issue. They have a recall on one of there engine for a bad tensioner and the parts are not even available to fix it. If one fails, they replace the entire engine. Even Better, all the engines are now on National back order... I am guessing they have a limited supply and what ever engines they might have in there possession are probably getting retro fitted. To add insult to injury, There are no Timing marks or Key ways. You need a series of tools to set the parts in there correct position. Once everything is set you installed, the bolts and the friction keeps everything pressed together...

 

[kidturbo]

Turn the tunes to 11..................... it'll be quiet then.

Been my wife's theory since I've known her.. Typically learn of an issue when I hear it pull in driveway...

 

[Dean E]

I am pretty sure they still install some sort of radio in these vehicles...

Personally, I think the Welt belts are a cop out.

Ford has the same issue. They have a recall on one of there engine for a bad tensioner and the parts are not even available to fix it. If one fails, they replace the entire engine. Even Better, all the engines are now on National back order... I am guessing they have a limited supply and what ever engines they might have in there possession are probably getting retro fitted. To add insult to injury, There are no Timing marks or Key ways. You need a series of tools to set the parts in there correct position. Once everything is set you installed, the bolts and the friction keeps everything pressed together...

Personally, I think the wet belt was the cheapest option. From a corporate point of view they look at the cost of the option and what market they have for it. From all of that they come up with a price point for selling it. If the cost of manufacturing the engine is too high they they look at cheaper options. That is where I think the plastic thermal control valve came from and the belt driven water pump came from. Since most people who would buy this truck new will never hold onto it to where the belt needs to be replaced they considered the problem solved. They now pushed the limit of the belt to 200k but the bigger deal here is resell value of the truck will take the hit. These engines will not hold their value as the miles crank up on them. Kinda sad especially considering how expensive these diesel trucks can be. Just one more reason I will keep my LMM in top running order. I have no issues putting a $1000 or $2000 from time to time into keeping it running perfectly. Still a whole lot cheaper than what payments and insurance are for these things. Dean

 

[1FastBrick]

Personally, I think the wet belt was the cheapest option. From a corporate point of view they look at the cost of the option and what market they have for it. From all of that they come up with a price point for selling it. If the cost of manufacturing the engine is too high they they look at cheaper options. That is where I think the plastic thermal control valve came from and the belt driven water pump came from. Since most people who would buy this truck new will never hold onto it to where the belt needs to be replaced they considered the problem solved. They now pushed the limit of the belt to 200k but the bigger deal here is resell value of the truck will take the hit. These engines will not hold their value as the miles crank up on them. Kinda sad especially considering how expensive these diesel trucks can be. Just one more reason I will keep my LMM in top running order. I have no issues putting a $1000 or $2000 from time to time into keeping it running perfectly. Still a whole lot cheaper than what payments and insurance are for these things. Dean

I agree its always a cost thing.

I thought they were really on to something when they released that engine until I found out about that wet belt design. I have seen a few post of those trucks being traded in before the 100K mark and the 2nd owner not doing the research and finding out that Truck needs to have the wet belt service performed. All that does is leave a sour taste for the brand when they have no choice but to repair the vehicle.

Same with the Ford Focus that my uncle bought. He needed transportation when his other vehicle broke down and that was in his price range. But the engine is supposed to go to 100K before it needs the wet belt service performed. Car Fax Does not show the engine and Turbo were replaced around 45k miles with the original owner in 2022. The 2nd owner had it about a year and got rid of it after around 12-15k miles. My uncle purchased it and only made it to about 65K when it overheated and left him stranded. 1 Shop quoted him 12k to replace the engine with a used lower mileage engine...
Looking around there in high demand and fetch a premium at around 4k for a used pull out... The stupid car barely has a $10K retail price. I looked into just doing a head gasket on the stupid thing and that's when I found out they have a 50/50 chance of having a cracked head. You also have to have special tools for the timing alignment. Ford doesnt event service them, they just replace the engine when there is a failure. So after some checking around we decided to get a new long block. That's when we found out about the backorder on the engine. I found a local dealer that just happen to have 3 instock. We purchased that and some other things and I think all in we have around 3K including fluids.

 

[Dean E]

I agree its always a cost thing.

I thought they were really on to something when they released that engine until I found out about that wet belt design. I have seen a few post of those trucks being traded in before the 100K mark and the 2nd owner not doing the research and finding out that Truck needs to have the wet belt service performed. All that does is leave a sour taste for the brand when they have no choice but to repair the vehicle.

Same with the Ford Focus that my uncle bought. He needed transportation when his other vehicle broke down and that was in his price range. But the engine is supposed to go to 100K before it needs the wet belt service performed. Car Fax Does not show the engine and Turbo were replaced around 45k miles with the original owner in 2022. The 2nd owner had it about a year and got rid of it after around 12-15k miles. My uncle purchased it and only made it to about 65K when it overheated and left him stranded. 1 Shop quoted him 12k to replace the engine with a used lower mileage engine...
Looking around there in high demand and fetch a premium at around 4k for a used pull out... The stupid car barely has a $10K retail price. I looked into just doing a head gasket on the stupid thing and that's when I found out they have a 50/50 chance of having a cracked head. You also have to have special tools for the timing alignment. Ford doesnt event service them, they just replace the engine when there is a failure. So after some checking around we decided to get a new long block. That's when we found out about the backorder on the engine. I found a local dealer that just happen to have 3 instock. We purchased that and some other things and I think all in we have around 3K including fluids.

Wouldn't it be wonderful if these kids who are engineers these days were to design an engine if mechanics were allowed to inspect and sign off on the new design before it could go into production! Needless to say that will NEVER happen. I know back in the day Bill Lear (who designed the Learjet) would go on the maintenance floor and look at the mechanics working on his jets. If he saw the mechanics having issues with the engineering prints that had to work with he would go upstairs and get the engineer who did the work on that drawing. He would drag them down to the main floor and make the engineer show the mechanics how it was supposed to work. Needless to say, 99% of the time the engineer went back to the drawing board to redo drawing he had put out! I'm afraid those days are LONG past us!

I really had high hopes for the 3.0 Duramax, I do think there is a good market out there for an engine like that even with all the EPA mandates coming down. It is just sad that stuff like this shows up on a clean sheet design. I just pray my LMM has a good long life ahead of it. I just freshened it up last summer with a two tone Katzkin leather interior and it looks great! The original SLE cloth had seen better days after all these years. Dean

 

[2004LB7]

Wouldn't it be wonderful if these kids who are engineers these days were to design an engine if mechanics were allowed to inspect and sign off on the new design before it could go into production! Needless to say that will NEVER happen. I know back in the day Bill Lear (who designed the Learjet) would go on the maintenance floor and look at the mechanics working on his jets. If he saw the mechanics having issues with the engineering prints that had to work with he would go upstairs and get the engineer who did the work on that drawing. He would drag them down to the main floor and make the engineer show the mechanics how it was supposed to work. Needless to say, 99% of the time the engineer went back to the drawing board to redo drawing he had put out! I'm afraid those days are LONG past us!

I really had high hopes for the 3.0 Duramax, I do think there is a good market out there for an engine like that even with all the EPA mandates coming down. It is just sad that stuff like this shows up on a clean sheet design. I just pray my LMM has a good long life ahead of it. I just freshened it up last summer with a two tone Katzkin leather interior and it looks great! The original SLE cloth had seen better days after all these years. Dean

I've believed this all my working life. Doing maintenance for most of that. I've always thought the guys designing something need to be the ones to do the maintenance and repairs during the testing and trials before the main release. Minimumly.

I have a similar issue here with the hotels Indo maintenance in. Every renovation the rooms get darker and darker and guests keep complaining but designers and architects keep specifying lamps and bulbs with less output. Furniture, cabinets, fixtures, etc are also getting cheaper and more difficult to keep in good shape. The owner, architect and construction manager need to spend at least one week in one before signing off on the whole building