Diesel Engine Sounds like bucket of bolts when starting

[SuperGewl]

Have the oil changed and all the filters. This time use a high quality oil, preferably 100% synthetic. Yes it cost more but it lubricates the engine better and aids in startup better by staying on the parts of the engine vice draining off after sitting for long periods of time.

[Jim_HiTek]

Fine advice so far.

Mine started sounding like a bucket of bolts suddenly as well. And smooth out after 10-15 minutes. Turned out that there is a vacuum pump mounted to the frame rail near the engine that was going bad. But it worked for months after I first started hearing it. Couldn't locate where the sound was coming from (but didn't try very hard either). Turned out that vacuum pump runs the dash air controls and the cruise control, when they died, checked the diagrams, got serious about finding it, and this forum helped. Disconnected the pump motor and the sound disappeared.

[karencollins]

Thanks everyone for all the information. We had recently changed oil & filters (we did use high quality on all including synthetic oil). However, we moved a couple days ago. I had Cummins tech support programed into my phone so they could here the noise & see if they had any suggestions. When we started the rig, there was no noise. We are beginning to wonder if we'd gotten bad diesel or someting. We'll move again at the end of this week & hopefully no more problems. However, I'll be saving these replys to my favorites, so if it recurs, I'll be back to reading them. Appreciate all your help!!