[Randall Raines]

Quote: Originally Posted by DaFlake (original)

As for the suction, there are a lot of different thoughts on this and most will say that it is better to drain from the bottom. Most in the USA will only drain from the bottom as suction devices don't get all the oil out or any sludge that might have built up.

I don't normally use these myself for oil changes, however I do use them to remove oil and fluids from cars that are having parts removed, they can also be very useful for the bleeding of the brakes and clutches .

A lot of the sludge doesn't normally come out of the engine through the sump plug anyway, (even more so if your trying to rush / do the job quickly) unless you use an engine flush and take your time and let it drain quite a while (leave the flush in too long and in extreme cases it can damage the rubber seals (make them soft)), even then, if you took the rocker-cover off / engine apart you would still find some sludge in there

I can see your point though .