I think the cummins mechanic is full of it.

Less coast down equals less fuel economy.
Otoh, if you're a full speed then hard braking driver, might as well let it assist.

I've found the 3.0/1500 to give less engine/transmission braking during coast down than the 4 generations of 6.6/2500 that I've run.

 

I figured it out on another forum. The 3.0 Dmax doesn’t have an exhaust brake. Tow/haul mode just changes downshift pattern to give some braking that way.

 

Beg to differ, my truck definitely has a butterfly type valve after the DPF and in front of the resonator.

 

Pretty sure the 3.0 duramax has an exhaust. Brake they just call it a grade braking device

 

Either way you don’t need to run it all the time on the Pete’s freightshakers 💩ernationals most have a switch for exhaust brake or jake brake low high and off just don’t forget to use it at all just because we have had guys do that and the soot build up causes sticking issues but the big trucks need them most of the time to assist with braking because of the heavy loads

 

Welcome to the SS forum.
Not a diesel guy, can't add anything.

 

Thanks for the input guys. I guess I will continue to play with it, but it seems that there is no reason to run it daily, other than it turns off that stupid auto off system!

How do I know when it’s doing a regen?? Does it run differently? I’ve heard the DIC shows a message to “keep driving”. I have 1000 miles on the truck, (bought it with 16,000 on it)and have never seen a message or felt a regen.
Thoughts?

 

You’ll know when it’s doing a regen you’ll have to stop and let it idle up a light will appear on the DIC or a message

 

The easiest way is, once the engine is up to temperature, it will idle at 1000rpm during a regen, as compared to the normal idle of about 700rpm.

 

No regen message.
Regen only takes about 12 miles on the 3.0.
Regen is one of the things that will cause a slightly higher idle.

You might be able to tell from the fuel economy page that it is in regen due to economy 'lower than expected for current speeds/loads'.

I was able to detect the difference in the exhaust tone when my 6.6's were in regen. I find the sound much more difficult to detect when running the 3.0's.

 

Good info. Thanks!

 

you can use exhaust/turbo brake as much as you want.

 

I installed the Banks Idash and pedal monster. The idash can be set to alert you when the Regen is occurring. Until I installed it I couldn't tell when my 2022 GMC 1500 Duramax was in regen.