chrysler dealers sell a top end cleaner - its very potent, you also would need to drain the oil really thorougly to ensure its not trapped anywhere in the engine or the oil cooler.

Kreen also make a top end cleaner which is advertised only to be used professionally. Its the real mustard when it comes to cleaning carbon.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)