So bought this unit used about 20 months ago. Just did a bunch of maintenance I should have done when I bought it: drained coolant, flushed and refilled; greased it all, checked/cleaned air filters, changed oil and filter etc. I did change oil and filter when I bought it so this is the second time I changed oil. Checked oil level after I filled it and it was clear as expected. Then started it up, dove it out of the garage. Rolled the deck under it and then fired the unit up a couple times to check/fix leveling and height. Then drove it back in the garage and checked oil again. Oil was already black! Is that normal after about 4 starts and maybe 4 to 5 mins of running? My Duramax doesn't get dirty nearly that quick.
VDO
VDO