Bellow
Hardcore MB Enthusiast
I know the OP has made his decision but in praise of oil analysis as a tool useful beyond merely establishing drain intervals. An analysis alerted me to a minute quantity of coolant in the oil from leaking inlet manifold gaskets. Left unattended that develops into serious water contamination or worse, a cylinder filling with coolant when idle and bending a conrod on next start-up. I've also on another engine seen 'dirt' (silicone) pointing to an air filtration problem.
One I saw on another thread recently was of a guy running a high mileage engine and having the oil sampled at every oil change. The results were always good showing little wear. One morning he started it up and got a 'low oil pressure' warning. On investigating he found swarf in the oil which was aluminium from the timing chain contacting castings. The cause of that was a broken tensioner part of which had reached the sump and partially blocked the oil pump inlet. The point he made though was that had he not known through the ongoing oil analysis that the engine was in good health he'd have assumed the low oil pressure was due to its high mileage and he'd not have investigated - just run it until it died. As it was, his early intervention saved the engine which is still running strong at some 250,000 miles. Oil analysis is an incredibly useful tool.
One I saw on another thread recently was of a guy running a high mileage engine and having the oil sampled at every oil change. The results were always good showing little wear. One morning he started it up and got a 'low oil pressure' warning. On investigating he found swarf in the oil which was aluminium from the timing chain contacting castings. The cause of that was a broken tensioner part of which had reached the sump and partially blocked the oil pump inlet. The point he made though was that had he not known through the ongoing oil analysis that the engine was in good health he'd have assumed the low oil pressure was due to its high mileage and he'd not have investigated - just run it until it died. As it was, his early intervention saved the engine which is still running strong at some 250,000 miles. Oil analysis is an incredibly useful tool.