A few newish European cars now have no sump plug and the oil is sucked out of the dip tube when changing it, I can't think of a more stupid idea, but there must be a reason for it, anyone any ideas?*

I like to look at how things are done on new cars when I get chance (incase there are things to be learned and applied to my own older car), but I just can't get my head around some of the weird things I see sometimes - I had a look at the intake manifold that was removed from a VW turbo diesel, the inlet was at one end, it ran along, did a U-turn, back the other way, another U-turn then went into the plenum, but why? Why make the air go further and round more flow losing U-bends? Noise reduction perhaps?filter

*It would be too easy to say it is to thwart any keen DIYers as hardly any 'normal' people get their hands dirty these days and for those that want to the tools to do the job are readily available....

Any additions or answers appreaciated.

///////////////////////////////////////////

I'd guess a sump plug costs around $3, and will cause a small but discernable number of oil leaks, and within the warranty life of the vehicle sucking oil out of the dipstick is acceptable.

So far as the manifold goes, all sorts of reasons are possible, noise is quite likely the main one.

I suspect cost is the main factor as Greg stated above but ham fisted mechanics stripping the thread in an alloy sump will also be a consideration.
Had this happen with my car at an authorised dealership !

By the way this is not a new idea...I first saw it advertised at a national franchise car wash and vacuum clean distributorship in the late 1970's.

The idea being anyone who knew where the dipstick was could carry out an oil change.
Never tried it myself.

Probably there is no sump plug for same reason automatic gearboxes don't usually have sump plugs - it can't come loose if there isn't one.  Car engines in boats have been having their oil changed by sucking it out for years. 

A lot of new cars (particularly European, but probably others as well) have a plastic belly-pan underneath the engine, mostly for aerodynamic reasons, although it helps with keeping debris and dirt and direct water splash/spray out of the engine compartment, too. If you use a drain plug, the belly pan has to come off, typically with a lot of screws (my VW diesel is like this). It's less labour to suck it out from the top, and a lot of people do this with the VW diesels ... although I prefer to do it the old way, if nothing else but to have an excuse to look around underneath for signs of other fluid leaks, cracked CV boots, and the like. VW still puts a drain plug there.

I don't know why they don't just put a small access hole in the belly pan to allow the drain plug to be reached without taking the whole belly pan off. I've thought about doing that myself, but every time I'm doing an oil change I can't be bothered, so it's never gotten done.

MORE NEWS