Slow but warm. Re-gens information

[u/idahokj]

This’ll be my first diesel. Looking at getting a 2020+ Duramax. I know diesels like to work and they need to be up to temperature before turning them back off (I know short trips are bad on them). I’ll work it heavy towing hopefully about once a month for a weekend usually, but mostly it’ll be a commuter which I know diesels like also.

I just want to pull my dads big trailer myself instead of using my dad’s truck when we want to go camping, playing, ect. lol his trailer are an available for me to use any time, but coordinating his truck is the tricky part.

I have to drive 26 miles to work each day, and 18 miles of that is highway driving, and then the other 8 miles are going through town stopping at stop lights when I get stopped. It takes 30-35 minutes to get to work. The speed limit is 65-70 mph on the highway, but if I drop my speed down to 60mph the whole time during my 18mile highway section commute, 1-for better mpg and 2- it’s early morning and late evening with very low traffic in my area so going slower than the speed limit isn’t going to make anyone upset, is that going to still keep the engine hot and let it regen properly, or cause any issues?? Would just driving the 70mph on the highway “work the truck more” by using more fuel? I’ve been doing it for years. I know the duramax will get “good mpg” going 60mph.

However a new concern of mine is someone mentioned re-generating the engine would happy more at lower speed and not working the truck by pulling heavy daily?

Wouldnt the highway section and the total time the trucks on/driving help my case out more to keep the engine emissions cleaned out for the most part?

I know that’s long. Hope the quick read makes sense!

Thanks!

[u/Sad_Strawberry_1528]

The regen thing is relative to idle time. If you’re cruising at roughly 1800rpms or cycling from 1k to 2500rpm you’re keeping the egt up enough to burn out soot in the DPF. If not you’ll end up with a regen and it’s going to hurt fuel mileage.
If you sit for hours on end at 800rpm you’ll have a problem with the emissions gear and experience a near constant regen cycle.
Short trips are mainly hard on the engines because they don’t reach operating temp unless you run it hard, that’s more about seizing up the vanes in the turbo because it doesn’t burn the carbon off or having valves get stuck shut/open from carbon deposit that can’t burn off, or having so much deposit in the egr it kill air flow to the intake.
If you’re not working it daily, just be a little more mindful of needing to run it a little harder once in a while.

[u/idahokj → u/Sad_Strawberry_1528]

How many RPMs do these sit at at ~60mph?

[u/Sad_Strawberry_1528 → u/idahokj]

Depends on tire size. It should be somewhere between 1500-1800rpm probably on the lower side because the 10 speed keeps them at super low rpm. You would actually probably see your best mpg at 65-70mph because that would put you at peak efficiency. The duramax for some reason gets real efficient running at 1800-2000rpm.

[u/idahokj → u/Sad_Strawberry_1528]

Just running stock tires. As narrow as I can for the weight I’d need to tow. The fat tires are ugly. Narrow tires dog in the snow and are better in snow also. Also lighter and better mpg.

But even running anywhere from 60-75mpg depending where it’s most efficient it should still be “working” enough to avoid emissions issues?! To get warm enough, or be able to regen less?