3.0L Duramax - who owns or has driven one

steve841 · April 12, 2020

24 minutes ago, Ninjaspot said:

Thank you for this thread and site. Just bought 2020 Sierra with the 3.0 Duramax and had never owned diesel before so was pretty overwhelmed reading the manual. However many of these posts put my worries at ease.

Now if I can figure out how to remove the rear view mirror cover so I can hardwire my radar detector\dash cam combo without destroying it....lol

Pics:

https://1drv.ms/u/s!Au8KKHL6Oauug4VZtJ_yrAnE6wB0zg

https://1drv.ms/u/s!Au8KKHL6Oauug4VaKSw06WAhkfqDgg

Start here https://www.gen5diy.com/

Just pull down on the rear tab against the headliner with a trim tool. That piece is not fun to put back, so try to put it together and THEN remount it to the windshield.

Pinnacle · April 13, 2020

On 4/4/2020 at 5:45 PM, RLit9 said:

Out with the old 2016 Colorado & in w/the new RST. Gotta say, I really enjoyed they Colorado for 70k trouble free miles. What a great truck & motor. However, the 3.0L is another level. It has none of the quirks that sometimes frustrated me on the Colorado. Clocked 28.1 mpg on the way home, which is on par w/the Colorado when it was stock. That is just silly for a full size truck. Hopefully its as trouble free as the Minimax!

Im in the market for your minimax shoulda sold it to me lol

Keinsi · April 15, 2020

Looks like I'm a bit late to the party but since the party appears to still being going strong, I'll add my input.

Just purchased a 2020 Silverado LT Z-71 3.0 Duramax and really enjoying the truck so far. The COVID-19 slow down has me working from home much more so I still haven't put more than 800 miles on the truck and averaging 22mpg. Mileage should be a bit better and may get better with time but I'm sure the Durtracks are hindering the mpgs.

Like many of you, I traded in a '16 GMC Canyon with a 5.5 BDS/Fox lift, 33" tires, and the 2.8 Duramax. Great to look at and great fuel economy (23mpg avg) but not so much fun on the road. Felt like I was about it roll it going around most corners at anything over 50mph.

The new Silverado 3.0 Duramax and 10-spd transmission is so much better than I anticipated. I've owned a stock Cummins 5.9, fully tuned Cummins 5.9 with built transmission, 3.0L Audi with 8-spd transmission (awesome), and 6.0L gas Silverado. This combination is the best by far and even eclipses the Audi for both torque and HP. If you are reading these threads and on the fence about purchasing one, don't be. Just jump to this side. As you can see from our reviews the water is fine. And if something does go sideways, the 5yr/100,00mile warranty is there to "help" us.

There are many things that I dislike about the truck but none of which have to do with the engine or transmission. Will just take what I have and slowly make it what I want with a build-thread to follow in the near future.

steve841 · April 16, 2020

Well, I finally got to tow my usual trailer which is around 3000lbs loaded but tall ... so its live a freakin parachute on the back.

On my 19 with a 6.2L, it'd get at best 12 mpg. The usual MPG at 70mph was 9-11.

Today on the 20 3.0L, I was averaging 10-13mpg in very windy conditions with cruise set to 71mph. I expect better mpg with less windy conditions.

But the real stat that made me happy, I pulled back into my driveway with 1/4 tank left. With the 6.2L, I had to fill up before the last 50 mile leg.

So, in my book, this is a win.

redvettez06 · April 16, 2020

21 hours ago, Keinsi said:

Looks like I'm a bit late to the party but since the party appears to still being going strong, I'll add my input.

Just purchased a 2020 Silverado LT Z-71 3.0 Duramax and really enjoying the truck so far. The COVID-19 slow down has me working from home much more so I still haven't put more than 800 miles on the truck and averaging 22mpg. Mileage should be a bit better and may get better with time but I'm sure the Durtracks are hindering the mpgs.

Like many of you, I traded in a '16 GMC Canyon with a 5.5 BDS/Fox lift, 33" tires, and the 2.8 Duramax. Great to look at and great fuel economy (23mpg avg) but not so much fun on the road. Felt like I was about it roll it going around most corners at anything over 50mph.

The new Silverado 3.0 Duramax and 10-spd transmission is so much better than I anticipated. I've owned a stock Cummins 5.9, fully tuned Cummins 5.9 with built transmission, 3.0L Audi with 8-spd transmission (awesome), and 6.0L gas Silverado. This combination is the best by far and even eclipses the Audi for both torque and HP. If you are reading these threads and on the fence about purchasing one, don't be. Just jump to this side. As you can see from our reviews the water is fine. And if something does go sideways, the 5yr/100,00mile warranty is there to "help" us.

There are many things that I dislike about the truck but none of which have to do with the engine or transmission. Will just take what I have and slowly make it what I want with a build-thread to follow in the near future.

Damn I go back and forth so much between the 5.3/8-Speed and the 3.0/10-speed and this post just edges me towards the diesel. I've test drove only the diesel and loved it (probably a mistake to start there, lol), but I was wondering if I should just save the ~3-4 grand that it would cost me to step up to the diesel. I plan keeping this thing 10 years so reliability is a big factor for me.

Duramax3oh · April 16, 2020

47 minutes ago, redvettez06 said:

Damn I go back and forth so much between the 5.3/8-Speed and the 3.0/10-speed and this post just edges me towards the diesel. I've test drove only the diesel and loved it (probably a mistake to start there, lol), but I was wondering if I should just save the ~3-4 grand that it would cost me to step up to the diesel. I plan keeping this thing 10 years so reliability is a big factor for me.

After 2 months now with mine, here's my kind of advice if I had to choose between the two:

5.3 - would make the most sense if you don't really do that much driving and if it's just fairly quick and short trips throughout the city. If you don't tow anything and it's mainly just a city truck, you're best bang for your buck is likely the 5.3

3.0L - makes more sense if you're driving quite a bit, longer trips or good stretches on the highway. The gas mileage is simply awesome. I made a 700-mile run a couple weeks ago before I had to stop to fill up. It's a joy. If you do light-medium load towing, this would make the most sense because of the low end and consistent torque, it pulls extremely easy and gets better gas mileage while towing.

Those are more of the practical matters. The other is "what do you want" which is a big part of owning truck. Some, the 5.3 V8 might be better, slap on some exhaust, etc... others (like myself) want that other kind of "it" factor that the Duramax diesel provides. It's just different. And I love it.

Edited April 16, 2020 by Duramax3oh

MTU Alum · April 16, 2020

On 4/1/2020 at 10:48 PM, redwngr said:

Video interview of one of the GM engineers suggested part of it is better aerodynamics on the silvy.

The other part is the way the tests are done. EPA requires that if an option is purchased on a certain % of vehicles that the impact (weight?) of that content be included in the testing. Sierra's, on average, have more added content and/or higher trim -- and that impacts the epa rating.

You have to use EPA mass when certifying fuel economy. EPA mass is base curb plus any option over 33% take rate. GMC has more models with higher option content which bumps it to a higher test weight class. The higher test weight class lowers the fuel economy. Chevrolet typically tests with a LT trim whereas GMC is typically Denali.

#iworkforGM

Rubyralph · April 16, 2020

20 hours ago, steve841 said:

Well, I finally got to tow my usual trailer which is around 3000lbs loaded but tall ... so its live a freakin parachute on the back.

On my 19 with a 6.2L, it'd get at best 12 mpg. The usual MPG at 70mph was 9-11.

Today on the 20 3.0L, I was averaging 10-13mpg  in very windy conditions with cruise set to 71mph. I expect better mpg with less windy conditions.

But the real stat that made me happy, I pulled back into my driveway with 1/4 tank left. With the 6.2L, I had to fill up before the last 50 mile leg.

So, in my book, this is a win.

Barring the mileage, how did the 3.0 Duramax do towing your tall trailer compared to the 6.2?

ie : RPM at highway speed (70MPH) downshifting / upshifting etc.

Thanks Ralph

steve841 · April 16, 2020

1 minute ago, Rubyralph said:

Barring the mileage, how did the 3.0 Duramax do towing your tall trailer compared to the 6.2?

ie : RPM at highway speed (70MPH) downshifting / upshifting etc.

Thanks Ralph

Ran around 1800-2000rpms.

Never once did it downshift, even in the headwind. SOLID TOWING VEHICLE.

My 6.2 would struggle in a headwind to find the "right" gear and regularly downshift, settle, shift up and then repeat the cycle.

Im totally sold at this point on the diesel.

redwngr · April 16, 2020

2 hours ago, MTU Alum said:

You have to use EPA mass when certifying fuel economy. EPA mass is base curb plus any option over 33% take rate. GMC has more models with higher option content which bumps it to a higher test weight class. The higher test weight class lowers the fuel economy. Chevrolet typically tests with a LT trim whereas GMC is typically Denali.

#iworkforGM

Thanks.

Much better wording of the explanation than mine.

Rubyralph · April 16, 2020

2 hours ago, steve841 said:

Ran around 1800-2000rpms.

Never once did it downshift, even in the headwind. SOLID TOWING VEHICLE.

My 6.2 would struggle in a headwind to find the "right" gear and regularly downshift, settle, shift up and then repeat the cycle.

Im totally sold at this point on the diesel.

That's excellent news!!

My 2017 5.3 struggled to pull my empty aluminum extra tall enclosed trailer with the six speed transmission, that's one of the reasons I traded it in on my new 2020 3.0 Duramax! I can't wait to tow after the engine break in, I really like the way this new truck accelerates and shifts.

ChuckTaylor · April 18, 2020

Anyone towing in the 7000-9000 lbs range care to comment? Debating between this and a Diesel HD - tow about twice a month, with a few weeks of straight towing here and there.

steve841 · April 18, 2020

1 minute ago, ChuckTaylor said:

Anyone towing in the 7000-9000 lbs range care to comment? Debating between this and a Diesel HD - tow about twice a month, with a few weeks of straight towing here and there.

As soon as the crap closings of boat ramps is over, I'll be towing 9,000 lbs to the boat ramp.

ullose272 · April 18, 2020

I love my 3.0 dmax, towed a trailer around town yesterday, about 4000 lbs, was like nothing, waaaaay better than my 14 with a 5.3. Love that i get nearly 30mpg on road trips, and love all the bottom end this thing has, and the 10 speed is amazing. If you plan to do bigger tires, id try to find one with the off road package that comes with 3.73 gearing.

Sent from my SM-G973U using Tapatalk

Cavjock22 · April 18, 2020

900 Miles into owning a Z 71 with a 3.0. So far loving it. Fuel mileage is very impressive. The highest at 31 setting the cruise on 65 on the interstate. I am averaging about 28 cruising at 75. I have had a check engine light on various times. I took it to the dealer and they said is sensor out on the emission package. The light seems to come and go as it desires. It has not affected mileage or running . The sensor has been on order for about a week and a half now. The dealer thinks they’ll have it in by next week. I’m not holding the dealer responsible or GMC responsible for the part delay due to the current environment we are in. so far I’m very happy with the purchase.