GM I6 Diesel Impressions

[Haoleguy]

Yikes ! Was this the storm from this past week ? We were lucky to have rain only down here. That picture shows it to be a heavy wet snow. BTW is your new 1500 black on black?

 

[bdeboer]

Thanks for the write up, my 2012 Silverado 1500 has around 145k on it. Starting to look a little

 

[s219]

I was talking about the Silverado somewhere back there wasn't I? So anyways, I'm 5 tanks into the little I6 diesel and my calculated average is 28.6mpg cumulative, with a best single tank of 30.8 and a worst of 27.3. the on-board mpg calculator seems to be a half mpg plus on the low side compared to hand calculating the mileage. I'm still not sure if its justifiable to have the diesel, but it's certainly not horrible. The sicker difference between a 5.3 and a diesel is about $2500, so it's not a price killer like when you go the 2500/3500 route and need different transmissions too. I think my favorite thing is the once-a-week fuel ups. I had to fuel up about every 4 days with the Colorado, and the 2500HD would only get me 2.5 days between fuel-ups. With the 24 or 26? gallon tank - I forget, I'm easily able to go at least 600 miles of routine driving before a fill up now.

I have been thinking about updating my 2014 Sierra 1500 to a 2020 model since the incentives are pretty strong. Have the 5.3L engine now and it's been good, gives me 19-22mpg regularly. Am considering all the engines, and the new I6 diesel is appealing. Thing is, the cost of diesel fuel is enough higher than gas in this area that it kills any fuel efficiency $$ benefit to the diesel engine. So not sure what I'll do. I want to test drive that engine though, and the 6.2L too.

 

[LouNY]

I have been thinking about updating my 2014 Sierra 1500 to a 2020 model since the incentives are pretty strong. Have the 5.3L engine now and it's been good, gives me 19-22mpg regularly. Am considering all the engines, and the new I6 diesel is appealing. Thing is, the cost of diesel fuel is enough higher than gas in this area that it kills any fuel efficiency $$ benefit to the diesel engine. So not sure what I'll do. I want to test drive that engine though, and the 6.2L too.

I haven't driven the Chevy 6 yet but I do have the RAM V6 diesel, will the mileage ever pay for the cost differential, NO..
That said the smooth low end torque delivery of the diesel reminds me of the way the old big blocks would pull at low rpm.
My max torque is around 1600 rpm and that little motor just pulls nice and smooth, no fuss, no muss, no screaming rpm which is what I like.
Is it the motor for everyone, nope. Does it have some turbo lag when cold, yep. I still enjoy the way the motor just pulls unloaded or even over loaded.

 

[nybirdman]

I have been thinking about updating my 2014 Sierra 1500 to a 2020 model since the incentives are pretty strong. Have the 5.3L engine now and it's been good, gives me 19-22mpg regularly. Am considering all the engines, and the new I6 diesel is appealing. Thing is, the cost of diesel fuel is enough higher than gas in this area that it kills any fuel efficiency $$ benefit to the diesel engine. So not sure what I'll do. I want to test drive that engine though, and the 6.2L too.

My thoughts also;fuel is higher,DEF purchases,higher cost of oil changes;potential cold weather problems.I like what I read about the L6 but for me the 5.3 makes more sense.The diesel has to get 25 mpg to break even on fuel alone.

 

[lostcause]

Yikes ! Was this the storm from this past week ? We were lucky to have rain only down here. That picture shows it to be a heavy wet snow. BTW is your new 1500 black on black?

That storm was April 10. We got a foot of really wet and heavy snow. I haven't seen as much tree damage since the 98 ice storm. We always lose pine limbs in winter, but since the hardwoods have dropped their leaves they don't usually take as much damage, but this storm took out a lot of big hardwoods.

The truck is black with black interior, but not full blackout. I have chrome on the mirrors, grille & bumper, and silver painted wheels. My Colorado was a midnight edition full black on black. This was a function of what the dealer could easily get in a swap, and I'm good with the color & trim options. Most of the time I'm more than content to concede a little on some of the fine details. When I got this I had to rush to pick it up after they got it in because they weren't sure whether they were going to be allowed to be open the next day.


Lou said it best - these aren't for everyone. It's not likely that you can justify something like this down to the last penny, but the driveability factor is there in these small diesels. I took my Colorado diesel to Florida last year and going through the hills in Pennsylvania it was like being on an uphill slalom course. I had the cruise control set and the truck was just off idle going up and around everyone as they were using all the revs and gears they had. You have to learn how to drive one though. it's not just mat it and go. Gas engines generally have a constant uphill power curve, but these diesels can be over revved and you will be out of the torque curve at that point. When the fuel prices stabilize I have no clue where it will land, but since I had the ability to do a 5.3 test on an identical 2019 truck last winter I knew I was going to see 18.6mpg gas, so I'm getting a full 10mpg better, or more than 50% better economy. Right now with diesel at just a little better than $2 a gallon near me, it's pretty nice. Course, with gas at $1.40, that would be equally good too.

 

[ruffdog]

With the diesel, you get a longer warranty too. Two more years and 40k miles longer.

Chevrolet Silverado Diesel Models Offer This Benefit | GM Authority

 

[s219]

I'm still considering this engine in a new Sierra, and took a look at historical fuel costs for gas and diesel since 2010, and the effective MPG. Came up with this chart:

The chart shows the equivalent gas MPG of a diesel rated for 26mpg (that is the highway spec for the GM I6 in a 4x4 crew cab Sierra).

When gas prices are cheap, like they are now, 26mpg from diesel is the same as 18mpg from gas. The current batch of V8 gas engines from GMC easily beat that number. On the average though, the diesel ranges between an effective 21-25mpg, so on average it's going to be better than the gas engines. When fuel costs get high, the diesel gets into the 25-28mpg range, which is way better than the gas engines can do.

For reference, here are the historical costs of gas and diesel that went into this calculation:

 

[nforktractor]

Any perceived loss of money, due to increased fuel costs, DEF costs, etc., is more than easily made up by the amount of Torque you getting with the diesel. Have had a bunch of gassers and diesels, I'd take a diesel any day, the only application of where the diesel just didn't feel right was with a side by side, that has to be a gasser.

 

[LouNY]

Any perceived loss of money, due to increased fuel costs, DEF costs, etc., is more than easily made up by the amount of Torque you getting with the diesel. Have had a bunch of gassers and diesels, I'd take a diesel any day, the only application of where the diesel just didn't feel right was with a side by side, that has to be a gasser.

Yes, that low end pull is unbeatable. I like diesels.
I look at me buying a diesel in a pickup about like the person that gets the biggest v8 for once a year use.
Or a one ton for once a year use instead of a half ton for year round use, I just like it better and I'll pay a bit more if need be for it.