I have an issue with my 09 Mack cxu600. When the truck is loaded on a hill speed goes down to 7 mph and on a straight level down to 37-45 mph.
1 mechanic I took it to baked the filters and said it was that because it was requesting a manual regen and I wasn’t even starting it. Once he did the work said to drive it and it would go away:(obviously it didn’t)
He did that and it still kept doing the same thing.
took it to another guy. He fixed all the problems on the ecu…replaced 7th fuel injector and shutoff valve . He was able to make it regen and then reset the soot levels. Just got back to working today. And now it doesn’t have any lights in the dashboard but it still has the problem while loaded.
