Catman
New member
Anyone heard of sudden spikes in fuel consumption?
2023 AT4 Duramax, 3,800 miles. Up until yesterday I had been getting spectacular fuel consumption numbers...good ones...with a max mpg of 35.7mpg; averaging about 28 tank to tank and on interstates, 30 was common if not better. I don't push the speed or acceleration. As of yesterday, all that dropped to 20mpg including on the interstate for a half hour drive, worse than I'd ever seen even short tripping or in town.
Only change had been body work due to some person sideswiping a rock w my truck; truck was INOP for 8 weeks, with zero frame or mechanical issues.
I had thought regen, but online comments from expert diesel persons is that with the LZ0, it is invisible. However, it is accomplished per John Barta of GM, by leaving the exhaust valve open slightly longer to deliver hot gasses to the SCRF, thus burning off any particulates. As I understand it the engine has no particulate filter per se, it uses the SCRF. And...thats about all I know.
I have lots of experience with marine diesels including 4 cyl and 6 cyl 12 liter John Deeres, which of course don't have this stuff on them.
2023 AT4 Duramax, 3,800 miles. Up until yesterday I had been getting spectacular fuel consumption numbers...good ones...with a max mpg of 35.7mpg; averaging about 28 tank to tank and on interstates, 30 was common if not better. I don't push the speed or acceleration. As of yesterday, all that dropped to 20mpg including on the interstate for a half hour drive, worse than I'd ever seen even short tripping or in town.
Only change had been body work due to some person sideswiping a rock w my truck; truck was INOP for 8 weeks, with zero frame or mechanical issues.
I had thought regen, but online comments from expert diesel persons is that with the LZ0, it is invisible. However, it is accomplished per John Barta of GM, by leaving the exhaust valve open slightly longer to deliver hot gasses to the SCRF, thus burning off any particulates. As I understand it the engine has no particulate filter per se, it uses the SCRF. And...thats about all I know.
I have lots of experience with marine diesels including 4 cyl and 6 cyl 12 liter John Deeres, which of course don't have this stuff on them.
