2023 GM Duramax Diesel 3.0L I6 - Test Drive Impression

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

20IndyRam

Member
Joined
Feb 23, 2020
Posts
48
Reaction score
58
Location
Extreme Northern Indiana (Michiana)
Ram Year
2020
Engine
EcoDiesel
Final thoughts - better drivetrain the Ram (sans bizarre overheat), worse comfort and ride than Ram. Pricing now about the same.
My 2017 Laramie 2500 priced app. $52k, 2023 value for consumer price inflation is $68.5k. The problem today's price is consumer wages didn't go up as much as price inflation, and the $52k in 2017 was pricey to begin with. A Chevy HD 2500 with the gas 6.6L V8 costs about the same as the little diesel in the 1500, with half the fuel mileage.

EPA has made a mess of everything.
Curious why you thought the GM 3.0 inline was better than the Gen 3 RAM Eco? I've driven both (2020) and chose the Ram. I did like the exhaust brake on the GM.

Aside from that, the Ram had better power/torque/fuel economy, much better fit finish, and a much better ride. In short, I haven't had an issue in 44K miles and am very pleased with the Ram.

Most of the Diesels are now plagued by the Bosch CP4 recall. The Eco's seem to be fairing well with their lift pumps and low high pressure pump demands (I have used Hotshots ETD since new). GM has a track record of not using lift pumps on the previous Duramax diesels. That was reported to increase the likelihood of CP4 pump failures. Not sure if they took the same approach on the 3.0L inline, or whether it makes a difference on the smaller engine.

Still happy with the Ram.
 
OP
OP
HEMIMANN

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,663
Reaction score
16,769
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
Hey the one I had for work was a flatbed and a stick lol. It barely had enough power to tow a trailer and a forklift.

I drove an old Ford F700 gasser for a Landscaping Service in college. Don't know what the motor was in it, but for a ton and a half truck loaded with topsoil black dirt, it was a real mutt. So much so it had a split real axle. You had to have it in granny gears just to get it going. Boy, people didn't like being stuck behind me when I was loaded!
 
OP
OP
HEMIMANN

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,663
Reaction score
16,769
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
Curious why you thought the GM 3.0 inline was better than the Gen 3 RAM Eco? I've driven both (2020) and chose the Ram. I did like the exhaust brake on the GM.

Aside from that, the Ram had better power/torque/fuel economy, much better fit finish, and a much better ride. In short, I haven't had an issue in 44K miles and am very pleased with the Ram.

Most of the Diesels are now plagued by the Bosch CP4 recall. The Eco's seem to be fairing well with their lift pumps and low high pressure pump demands (I have used Hotshots ETD since new). GM has a track record of not using lift pumps on the previous Duramax diesels. That was reported to increase the likelihood of CP4 pump failures. Not sure if they took the same approach on the 3.0L inline, or whether it makes a difference on the smaller engine.

Still happy with the Ram.

ED is underdesigned - marginal crank and bearings. Many failures Gen 1, Gen 2 they tried to half-a$$ upgrade it, mandated higher viscosity engine oil to try to save it. Best read up on all the failures on these engines.

Bosch CP4 recall is on the bigger engines. Smaller engines have Denso, Stanadyne, or other reliable pumps. CP4 pump is cost-reduced CP3, has nothing to do with lift head. It is a cheap pump underdesigned for its purpose. Well documented by this point. It was all about maximum moola for Bosch - charge the same price for a cheapo.
 

Treburkulosis

Your High End Detailer
TOTM Winner
Joined
Mar 21, 2016
Posts
6,032
Reaction score
8,228
Location
Haslet, TX
Ram Year
2012 Lonestar Edition converted over to a Sport
Engine
5.7 Hemi
I drove an old Ford F700 gasser for a Landscaping Service in college. Don't know what the motor was in it, but for a ton and a half truck loaded with topsoil black dirt, it was a real mutt. So much so it had a split real axle. You had to have it in granny gears just to get it going. Boy, people didn't like being stuck behind me when I was loaded!
Sounds like the 90 Kodiak I drove for almost 20 years. Dang tough truck, but it was so slow.
 
OP
OP
HEMIMANN

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,663
Reaction score
16,769
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
I take it nobody active here has bought or tried one these other than moi?
 

ramffml

Senior Member
Joined
Jul 12, 2019
Posts
2,730
Reaction score
4,894
Location
ramforum
Ram Year
2019
Engine
hemi 5.7
I take it nobody active here has bought or tried one these other than moi?

I've driven the older 2.7, 5.3, and the older 3.0 from GM. I wouldn't get the 5.3 over my truck because why, less power in a v8. Loved the 3.0, and the 2.7 was very surprising; haven't driven the new variants which both make significantly more torque.

Back then the interior was quite bad, not sure the year I tested, 2019 + 2020 in the diesel probably.

I do like the new gms, but purchasing one for me at this point would be a side step and completely pointless considering what I want from a truck and how my truck is currently running. The diesel is very attractive to me, but horribly expensive given the entry trim level and I'd never make that deal work financially. But if I cracked up my truck? Yeah I'd be heading to the GM dealer for sure to take another look.
 

Travelin Ram

Senior Member
Joined
Jan 8, 2020
Posts
1,840
Reaction score
2,979
Location
Somewhere in NA. Probably. We travel a lot.
Ram Year
2022
Engine
6.4
I test drove one last year while truck shopping. I was impressed.

I’ve talked with owners and they seem well satisfied and reported mileage around high 20’s to 30.

Now that GM offers the diesel in a ZR2 I may give them another look. I’d probably be driving a ZR2 now if the Chevy dealer hadn’t tried playing the usual games rather than being straight with me.
 

20IndyRam

Member
Joined
Feb 23, 2020
Posts
48
Reaction score
58
Location
Extreme Northern Indiana (Michiana)
Ram Year
2020
Engine
EcoDiesel
Bosch CP4 recall is on the bigger engines. Smaller engines have Denso, Stanadyne, or other reliable pumps.
Wrong - the CP4-2 is used on larger engines. The CP4-1 is used on smaller. I currently have a recall for my 2020 EcoDiesel with the CP4-1 pump. The F150 3.0L Diesel also uses the CP4-1

CP4 pump is cost-reduced CP3, has nothing to do with lift head. It is a cheap pump underdesigned for its purpose. Well documented by this point. It was all about maximum moola for Bosch - charge the same price for a cheapo.
Wrong again - The CP4 is a higher pressure version of the CP3. It is less expensive, lighter, and more efficient. It's main failure mode is cavitation and lack of lubricity. This is why the lack of a lift pump (higher differential pressure) ABSOLUTELY contributes to the failures. As you said -WELL DOCUMENTED BY THIS POINT. Adding lubricant to our low sulfur fuels makes these pumps last. I'll let the lawyers figure out if that's worthy of a class action suit.

ED is underdesigned - marginal crank and bearings. Many failures Gen 1, Gen 2 they tried to half-a$$ upgrade it, mandated higher viscosity engine oil to try to save it. Best read up on all the failures on these engines.

I read up on the Gen3 ED before I bought it. You should do the same. There were failures on the Gen 1 and 2. Gen 3 has been very good. Unfortunately, they are discontinuing (I would have bought another).

On the flip side, you are pinning your homes and dreams on a Gen1 3.0L Duramax where you don't like the ride quality or Fit/Finish. Sorry, but I wouldn't buy a Gen 1 anything (including Toyota) particularly if I didn't care for the rest of the vehicle.

For your edification - here's the TSB list for the Silverado 1500 with the small diesel. Interesting that the have some related to "excessive fuel contamination" and "fuel additives". Doesn't sound anything like a high pressure pump concern - or does it?

Silverado 1500 3.0L Diesel TSB
 
Top