I used AMSOIL Engine Flush when I switched from conventional to synthetic after noticing a brown/black layer of varnish accumulating on my dip stick. I drained the old oil and put a new filter on. Then I put new conventional oil in with the bottle of engine flush. I ran the engine at a fast idle (1500-2000 rpm) in park for 20 minutes, drained the flush oil, and changed filters again. The 20 minute used oil was very black from all of the varnish and sludge it was cleaning out, so I was glad I spent the extra $15-$20 to flush with clean oil and a new filter. This is also one of the official documented uses for the Sea Foam Motor Treatment available at many auto parts stores.
I have not heard about flushing with ATF before, so thanks for the tip. I'll look into that too.
I have not heard about flushing with ATF before, so thanks for the tip. I'll look into that too.
