Ron240
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- #21
The way I look at this is....your Smart does not have a sump plug so it has been designed to have the oil sucked out, but the vast majority of cars do have sump plugs to allow draining of the oil. It is a relatively recent thing where oil can routinely be sucked out and this is done for the precise reason of time saving and therefore money saving.It makes not difference when it's drained or sucked out. My Smart Roadster doesn't have a drain plug on the sump pan, so in order to remove the sump pan on my car I sucked the oil out first. There was a spoon full of oil left in there.
It is probably safe to assume that the majority of engines will have more than a spoon full of old oil left in the sump after sucking out.
In the short term it will make absolutely no difference, but in the long term I still reckon draining is better.
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