Hi Eddie glad to read one is making good use of that carbon clean machine i told the boss to get rid of,we only used it a dozen times i think in the many years weve had it,eddie boss man only got £180 he gave me £20 for getting rid of it, he was going to put it in the skip for the aliens who take our scrap away every night, great fun next day with cuppa watching video, as for the engine flush we use wynns,only if its a new customer,the regulars dont need it just take a look on the dipstick if theres any oil in said oil tank or most commonly used wet sump, we wouldn't use it in dry sump systems though would we gents,at the end of the day get the customers to drop the oil change mileage if they want keep the engine as an engine,the manufactures want us to drive to mars and back before there product gets the attention it needs all in the name of quantity,and not enough quality,sorry for long post gents.