I have a 2021 VNL 860 with a volvo motor auto transmission. It has 150k miles on it. I wanted to know whether these new trucks do regen over the road ? Because mine does not or if it does there is no message on the display like my old 2014 volvo. The display says regen not required when I tried a parked regen.
Second issue is I hear an actual sharp whistling sound under the hood when I speed up. Only lasts for a few seconds. Coincidence is the turbo boost reads around 10-20 when it happenes. Is it turbo or belts ?