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"gm Ponders Reviving 4.5 Duramax V-8 Diesel"

Bryan410

By Bryan410
in Future GM News & Rumors

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fbachman Senior Enthusiast

fbachman

Posted
Posted

Personally, I would LOVE the option of a (more) reasonable diesel engine than the monster Duramaxes we see today.

 

I mean, I (personally) don't need enough torque to pull my hous off of its foundation idling along in "D". :thumbs:

 

I (personally) am not interested in 16qt oil changes and $50 oil filters.

 

Now, if there was a mid-sized diesel (like a 4.5) that I could get in a 1500, I would take a reaaaaaal long look at that at the time of my next purchase.

 

I think GM is fighting two battles here:

 

1) The historical (undeserved IMHO) perception of the role of the Diesel in passenger/light duty vehicles in the US. Never really got a foot hold here (relative to, say, Europe). Oddly enough, GM helped THAT along with the 350 Diesel fiasco of the late 70s...

 

2) The odd fact that Diesel is still significantly more expensive that gasoline in the US.

 

I grew up in Europe, and am, personally, quite open to Diesels in passenger cars/lighter duty vehicles, and recognize the fact that Europe, in particular (including GM's european sisters) have made GREAT strides in Diesel technology over the last several decades.

 

For a truck, even lower displacement Diesels give you gobs of Torque to do work, have a higher economical index than a similiar displacement gas engine, and, now-a-days, don't have the same clatter and black cloud syndrome that gave diesels a bad name here over the years. The emmissions technology has gotten better as well.

 

Now, Americal emmissions regulations for Diesels are so tough that even European manufacturers are having challenges meeting them. Seems like we are shooting ourselves in the feet.

 

I truly think that reasonable/smaller Diesels can play a huge role in allowing the full-sized pickup as we know and love today to get more longevity looking toward the future.

 

I say: "GM, full speed ahead". Then again, I am not the guy that has to make the business case for it, and I am sure there are a hell of a lot more variables to that equation than I know.

ryan_hermanutz Senior Enthusiast

ryan_hermanutz

Posted
Posted
With the new diesel emission requirements a 4.5L 1500 diesel does not make financial since. Diesels are no longer as fuel efficient as they were before ULS diesel came along in 2007 and the cost of ULS diesel has sky rocketed, no longer being priced lower than gasoline. Great idea at the time but goberment tree hugger red tape and GM's lack of money killed it.
c4cruiser Enthusiast

c4cruiser

Posted
Posted

A smaller diesel in the 1/2 ton truck would be a great deal for small businesses like contractors, landscapers and anyone else that has a need for towing/hauling power and doesn't necessarily have a need for a 3/4 ton truck. To many the 3/4 ton rig is simply overkill.

 

But would Chevy/GMC be risking hurting their 3/4 ton market? Wonder what the drop in sales would be if a small diesel (and the Allison 6-speed) was available for the 1/2 ton crowd??

 

Didn't Ford drop their small diesel engine concept for the F-150 about the same time? Seems that Ford would have similar concerns over sales of there F-250 diesel trucks if GM introduced a new diesel in a 1/2 ton. Ford would have to come with a similar package.

SLESierra Enthusiast

SLESierra

Posted
Posted

I could see a use for the new diesel. The 6.6 is just a powerhouse but the 4.5 is no slouch and it would give GM another avenue into the MPG game in the new updated fuel requirements. They could slip the 4.5 in the 3.4 ton and talk about bumping numbers.

BrockwayMT Enthusiast

BrockwayMT

Posted
Posted
Yup, gotta drop the "Diesels are not as fuel efficient as they were before" crap We are seeing a VERY strong improvement in fuel economy since the addition of DPF.

 

03-07 diesels are generally bad on fuel (best example the Ford 6.4) due to EGR. 2010 SCR engines are supposed to be much better on fuel because the SCR can keep the NOx down with much less EGR

 

 

GM did a lot of testing with the 4.5 LMK Duramax a couple of years ago. I heard a lot of positive feedback. At the same time Dodge was testing a 5.0 Cummins V8 that was supposed to go on sale early this year as a 2010 1/2. I don't ever recall hearing numbers for the Duramax. The Cummins V8 was around 275 hp IIRC and severely torque-managed at around 390 or 400 lb-ft.

jro909 Senior Enthusiast

jro909

Posted
Posted

i'd be looking at a half ton dirtymax if they came out, diesels are the way that america should go as far as fuel...we are far too big to go pure electric car, diesel can be made out of almost anything and they are alot cleaner then gassers...

  • 3 weeks later...
uh6tdrvr Enthusiast

uh6tdrvr

Posted
Posted

i dont remember the HP numbers but the tq numbers were suppose to be around 450. They wouldnt be able to keep them on the lot if they could get them to get in the upper 20s for MPG...id think that could be a pretty reasonable number and it would be hands down above the rest....what would you give to push your current truck to 27, 28 mpg on the highway and 21 in the city? id really like to see a little duramax in a suburban.

BigBlockV6 Enthusiast

BigBlockV6

Posted
Posted
i dont remember the HP numbers but the tq numbers were suppose to be around 450. They wouldnt be able to keep them on the lot if they could get them to get in the upper 20s for MPG...id think that could be a pretty reasonable number and it would be hands down above the rest....what would you give to push your current truck to 27, 28 mpg on the highway and 21 in the city? id really like to see a little duramax in a suburban.

The power was to be 350hp ! About 500tq !

 

They should pull into high mpg range easily !

My 6.5 K2500 gets 21mpg HWY n 19 mph CTY . . .

 

Tho on the flip side the 6.5 is unreliable and is anemic at best for performance . . .

 

 

Mike

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