Just bought a 2008 Sterling with a cummins 330 engine, has about 422,000 miles. I've read older posts about regen issues on this engine, but guess I thought that after this many miles that problem, if it was one, would have been taken care of already. Mistake on my part. Just wondering what has been done by others that have had issues with this, what finally corrected the problem? Seems as if the regen that is supposed to take place while driving does not happen, then it needs to continually have a manual regen. Any thoughts or remedies?