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Posted
22 hours ago, chris84 said:

Any updates from those who have been driving these?

I only have ~800 miles on my Duramax AT4, but so far I am very impressed. The powertrain feels light years ahead of the 2019 8 speed 5.3L AT4 that I traded in. 

 

No disrespect to 5.3L 8 speed owners, as I have owned 3 of that powertrain combo myself, but there really is no comparison for MY tastes. My last 8 speed (2019 AT4) was the best of the 3 I have owned... I really believe GM fixed a lot of issues with the changes they made to the 8 speed for the T1 platform, but it just was never truly smooth. The 10 speed Duramax combination on the other hand is smooth a silk. 

 

Only complaint: The Duramax seems to take much longer than the gas v8's to warm up. Gas mileage won't be great with the Duramax (in my limited experience) until it is fully up to operating temp. If a high percentage of my driving was short trips of say less than ~5 miles one way, I would probably prefer the gas.

 

The sound of the engine is great, nice and quiet, but you definitely know its a Diesel. Fuel mileage has been wonderful compared to my 2019 5.3L AT4. I listed some of my fuel economy numbers below, if interested. 

 

2020 Duramax AT4 (800 miles)

Best 25 - 33.3 mpg

Best 50  - 30.1 mpg

Best 400 - 25.1 mpg

LTD - 24.3 (a lot of idling early on without many miles to normalize - slowly creeping up)

 

2019 5.3L AT4 (5200 miles)

Best 25 - 24.5 mpg

Best 50 - 21.2 mpg

Best 400 - (didn't get a picture of this before I traded, but I believe it was in the low 19's)

LTD - 17.5 mpg

 

 

Both are literally the same exact truck down to the color, other than the powertrain of course. Same stock 18" wheels and factory duratracs. 

 

 

Posted
2 hours ago, larryz71 said:

I only have ~800 miles on my Duramax AT4, but so far I am very impressed. The powertrain feels light years ahead of the 2019 8 speed 5.3L AT4 that I traded in. 

 

No disrespect to 5.3L 8 speed owners, as I have owned 3 of that powertrain combo myself, but there really is no comparison for MY tastes. My last 8 speed (2019 AT4) was the best of the 3 I have owned... I really believe GM fixed a lot of issues with the changes they made to the 8 speed for the T1 platform, but it just was never truly smooth. The 10 speed Duramax combination on the other hand is smooth a silk. 

 

Only complaint: The Duramax seems to take much longer than the gas v8's to warm up. Gas mileage won't be great with the Duramax (in my limited experience) until it is fully up to operating temp. If a high percentage of my driving was short trips of say less than ~5 miles one way, I would probably prefer the gas.

 

The sound of the engine is great, nice and quiet, but you definitely know its a Diesel. Fuel mileage has been wonderful compared to my 2019 5.3L AT4. I listed some of my fuel economy numbers below, if interested. 

 

2020 Duramax AT4 (800 miles)

Best 25 - 33.3 mpg

Best 50  - 30.1 mpg

Best 400 - 25.1 mpg

LTD - 24.3 (a lot of idling early on without many miles to normalize - slowly creeping up)

 

2019 5.3L AT4 (5200 miles)

Best 25 - 24.5 mpg

Best 50 - 21.2 mpg

Best 400 - (didn't get a picture of this before I traded, but I believe it was in the low 19's)

LTD - 17.5 mpg

 

 

Both are literally the same exact truck down to the color, other than the powertrain of course. Same stock 18" wheels and factory duratracs. 

 

 

Nice comparison here. That's the trim I'm looking to get - you have the shorty bed or the standard?

 

I currently have a 16 5.3 8spd that is really disappointing, wish I had kept my 04 Duramax. Back & forth to work & short trips around home I get less than 13, & even on long highway trips I rarely get over 17.

 

Now I just need to find a dealer that will sell me an AT4 with the "standard" bed at what I'd like to pay.

Posted
8 hours ago, chris84 said:

Nice comparison here. That's the trim I'm looking to get - you have the shorty bed or the standard?

 

I currently have a 16 5.3 8spd that is really disappointing, wish I had kept my 04 Duramax. Back & forth to work & short trips around home I get less than 13, & even on long highway trips I rarely get over 17.

 

Now I just need to find a dealer that will sell me an AT4 with the "standard" bed at what I'd like to pay.

I have a short box. I wish I could have gotten the standard, but unfortunately it wouldn't fit in my garage. 

Posted
12 hours ago, larryz71 said:

I only have ~800 miles on my Duramax AT4, but so far I am very impressed. The powertrain feels light years ahead of the 2019 8 speed 5.3L AT4 that I traded in. 

 

No disrespect to 5.3L 8 speed owners, as I have owned 3 of that powertrain combo myself, but there really is no comparison for MY tastes. My last 8 speed (2019 AT4) was the best of the 3 I have owned... I really believe GM fixed a lot of issues with the changes they made to the 8 speed for the T1 platform, but it just was never truly smooth. The 10 speed Duramax combination on the other hand is smooth a silk. 

 

Only complaint: The Duramax seems to take much longer than the gas v8's to warm up. Gas mileage won't be great with the Duramax (in my limited experience) until it is fully up to operating temp. If a high percentage of my driving was short trips of say less than ~5 miles one way, I would probably prefer the gas.

 

The sound of the engine is great, nice and quiet, but you definitely know its a Diesel. Fuel mileage has been wonderful compared to my 2019 5.3L AT4. I listed some of my fuel economy numbers below, if interested. 

 

2020 Duramax AT4 (800 miles)

Best 25 - 33.3 mpg

Best 50  - 30.1 mpg

Best 400 - 25.1 mpg

LTD - 24.3 (a lot of idling early on without many miles to normalize - slowly creeping up)

 

2019 5.3L AT4 (5200 miles)

Best 25 - 24.5 mpg

Best 50 - 21.2 mpg

Best 400 - (didn't get a picture of this before I traded, but I believe it was in the low 19's)

LTD - 17.5 mpg

 

 

Both are literally the same exact truck down to the color, other than the powertrain of course. Same stock 18" wheels and factory duratracs. 

 

 

So, would you recommend the Duramax, say if I have a one way drive to work of 22 miles?

 

I do tow occasionally, but I would probably buy the Duramax for the gas mileage.

Posted
22 minutes ago, jaslon said:

So, would you recommend the Duramax, say if I have a one way drive to work of 22 miles?

 

I do tow occasionally, but I would probably buy the Duramax for the gas mileage.

That is my daily commute each way as well.  Probably 80% Interstate/Highway and 20% in town.  So far I am getting around 27MPG average.  RST Crew cab short bed 4x4 w/factory 20" Dueller ATs.

Posted

I have about 7400 miles on mine, bought last October. Had my first oil change at about 6500 miles according to the computer. Had to fill the DEF tank at about 6000 miles. No issues so far with the cold, truck was parked at work outside when it was about negative ten for about five hours and started with no issue, and that was with #2 diesel. Have it parked in a heated garage at night so don't have to worry about the cold nights. Have no issue averaging over 20 mpg this winter with only in town driving. That is with my larger duratracs. Currently averaging 21.4 this tank of around town driving but has been nicer this past week. Still enjoying the diesel power as this is my first, great engine/tranny combo. Have towed a little in town, probably around 8000 lbs with no issue. You definitely see the advantages of this truck with longer trips, whether just in town or out, don't think I would choose this truck if my daily trip is 5 miles to work, then sit all day, then go home, I think I would get the gas then. e476c0250e65677b1974f1bafde88020.jpg

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Posted
8 minutes ago, afterburner82 said:

That is my daily commute each way as well.  Probably 80% Interstate/Highway and 20% in town.  So far I am getting around 27MPG average.  RST Crew cab short bed 4x4 w/factory 20" Dueller ATs.

So, what is your average speeds that you are running?

 

I would be averaging between 60 to 65 mph if the traffic is running smoothly.

Posted
1 hour ago, jaslon said:

So, would you recommend the Duramax, say if I have a one way drive to work of 22 miles?

 

I do tow occasionally, but I would probably buy the Duramax for the gas mileage.

absolutely 

Posted (edited)

Absolutely reccomend the 3.0 in about 12 month's when parts are regularly available. I got mine on December 21 2019. It's an AT4 and there is so much I love about the truck. However, I am having a chronic issue with ABS - Braking and Stability System C0504 which then disables traction control and cruise control. I have had it serviced 3 times and they can't seem  to sort it out. The issue occours up to 3x a day and lasts for hours. On my way to Dealership for an oil change this morning ~9900 miles on the truck it went into limp mode. ECM - Engine System P06DD The powertrain system has detected a malfunction related to the oil pressure sensing system. An oil pressure warning light or message may illuminate. Fuel economy may be affected.and ECM - Engine System P25A2 The Engine and Transmission System is not performing as expected. An issue has been detected in the Engine Electrical System, including the Charging and Starting System that monitors and controls the engine starting system and 12V battery charging system. If the charge system light stays on, or comes on while driving, there may be a problem with the electrical charging system. Driving while this light is on could drain the battery. If a short distance must be driven with the light on, be sure to turn off all accessories, such as the radio and air conditioner. I will update as things progress. Not happy at all right now. This has put a serious jam into my work and life today. Before all this I am getting around 18mpg. My truck has a 6" lift and is on 35x12 tires. I have begun to haul with it but not excessive. If hauling heavier I get around 11mpg and lighter 13mpg and I am happy with it.  I Installed an airlift kit to eliminate squat and it also improved steering while hauling. 

 

UPDATE: the oil pressure regulator is bad. There are no parts currently available.  Detroit was contacted and they are on back order. Good news on ABS they found  debris in the speed regulator driver side front. So that will be fixed. Truck will be at dealership until a new oil pressure regulator is sourced and installed.

20200209_141035 (2).jpg

Edited by Joseph Mann
Service update
Posted

I bought a 2020 Silverado rst in December with the 3.0. I average 23 mpg around town and have hit 31.8 on the highway at 70mph. This is in a crew cab four wheel drive.  I traded my 05 LLY Duramax 2500 in so I was use to the big torque and low horsepower numbers.  The 10 speed auto makes this little motor a pleasure to drive.  It pulls hard up to about 3k where you can tell it just doesn’t have the horsepower of a gas motor.  It’s not an issue to me though because it’ll tug as hard as my 05 6.6 Duramax. That 10 speed and the 460lb ft of torque make it feel like it has allot more in it.  So far I’m at 5k miles since late December and it’s been rock solid.  Still have 1/4 tank of def as well.  I’m extremely happy with the entire truck overall.

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Posted
10 hours ago, larryz71 said:

absolutely 

 

11 hours ago, jaslon said:

So, would you recommend the Duramax, say if I have a one way drive to work of 22 miles?

 

I do tow occasionally, but I would probably buy the Duramax for the gas mileage.

I drive 55 miles each way to work

5 days a week and fill up once a week.  It’s something around 22-23 gallons to fill the tank.  Mostly highway.   

Posted
On 2/18/2020 at 9:14 PM, chris84 said:

Nice comparison here. That's the trim I'm looking to get - you have the shorty bed or the standard?

 

I currently have a 16 5.3 8spd that is really disappointing, wish I had kept my 04 Duramax. Back & forth to work & short trips around home I get less than 13, & even on long highway trips I rarely get over 17.

 

Now I just need to find a dealer that will sell me an AT4 with the "standard" bed at what I'd like to pay.

If you want a standard bed better come to the realization you'll need to order it, especially with the 3.0

I did -2020 Silverado HC 

Posted
5 minutes ago, ArTurf said:

If you want a standard bed better come to the realization you'll need to order it, especially with the 3.0

I did -2020 Silverado HC 

There are some 3.0's in crew/standard box trucks 'here'.

Including a few AT4 standard box ones.

Posted

Just throwing this out there. At what point mileage wise does the extra cost of the 3.0 over the 5.3 plus the higher cost of diesel even out? Not saying for or against just thinking. I was intrigued by this engine but went with the 6.2 

Posted
There are some 3.0's in crew/standard box trucks 'here'.
Including a few AT4 standard box ones.
Here is mine, got it right off the lot as soon as it showed up to the dealer1caf339c1b765cf2ce2e245496233a57.jpg

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