I've found everytime I've taken a car in for a service and got them to change the oil they only put in 4 litres.
Now the reason I know this is because I buy the oil (5 litres) and they always give me back 1 litre left in the container. The oil is definately full because I check it when I get home.
The last couple of years I've been changing my own oil (you all should) and always had to use 5 litres to get it to the full mark.

Makes me wonder how competent most mechanics are. They dont drain all the old oil so you end up having 20% crap oil mixed with the new stuff.
This is with 6 cylinders as well as the V8s.
I know professional mechanics have time constraints so they can make a profit but not draining all the oil is pathetic.

always do it yourself unless u know the mechs personally!

fraud are well fooked! same as most other places are only in it to make $$

Even if you do know the Mechanics personally why not still do it yourself? Unless your someone incapable (physically disabled, mentally handicapped, what ever - al;thoguth I'd be wondering why you have a car to drive then) there's no real reason why anyone can undo a sump plug, catch the oil, twist of a filter, twist on a new one, do up the sump plug and fill up with oil. It takes what 20 minutes if your listening to the radio and going slow.

Some people have better things to do.

If properly drained they take 5 1/2 litres

I beg to differ there, because I have been changing the Oil & Filter on my EL myself for the past 5 years and I always seem to be only able to fill it up completely with only 4.8litres of Oil even after waiting a day later to let ther Oil settle through out the Motor.

I think offyaguts was referring to the 302's.

But I definantly put 5L of oil into both my i6's and V8

I thought this was one of the good things about servicing the windsor... few hundred mL for the filter, throw the remainder into the engine... 5L of oil ALWAYS leaves the perfect amount in the sump...

So we are both right then! Give or take a Couple hundred ml's.
So that begs the question for Offyaguts how in the hell is he able to fit that extra 1/2 litre in Unless he is overfilling it?

Maybe they were not changing the filter and leaving the oil in it.

But what sound more likely, they do a change that quick they don't wait for all the oil to drain out.

I hope they start the motor to allow the new oil to go through the new filter, before checking the levels.
Stranger things have happened at some service joints.
I couldn't let someone charge me a bunch of cash for doing something easier than s**t in bed.

anyone look at it from a mechanics point of view?
for example. to do a minor srv on a ba falcon I6 you are given .8 of an hour.

go get the car complete a body check to confirm damage already on car before work starts and get it positioned on a hoist.
Check light operation , horn , handbrake , clutch , a/c.
pop the bonnet. coolant lv , p/s lv , top up washer bottle
hoses drive belt/s , leads ,wires , oil leaks and remove the oil cap.

hoist it up.

drain oil and change filter and wile it is draining check all underbody components..
Rubbers , boots , shocks , exhaust , Trans <-- EXT housing seal almost always rooted , driff , engine (leaks.. sump ect) , fuel lines , brakes and perform a tire wear check. sump plug back in. and lower it.

take off airbox lid, remove and blow out air filter, fill engine with oil and start. confirm oil light goes out and let idle for a few minutes wile you pump up the tires to the set psi including spare tire wich is normaly under a whole heap of junk... EG Prams , papers , tools and general s**t people keep in their boot. turn it off and go stamp the book and change the lube sticker. go back and check the oil and rectify its level if needed. take for a drive and confirm there are no other concerns with the cars operation.

do all that in 48 minutes.

Most mechanics see about 5 cars a day where i work, not all for services some with more major problems. it is not like there is great passion in changing your oil or something. its a job and we are given a time to do it in and paid bugger all. you go over time and you get your a** kicked. just thought i would give you a run thru of what its like on our side. i am sure there are dodgy places that do some pretty screwed up stuff but thats life eh.

not trying to flame of anything but there is 2 sides to the story my advice would be do it yourself. i wouldnt have anyone but me work on my car because i know the job is done and its done right the first time.

Yeah i suppose, and i guess it leaves you with one option. If you want all the oil out, make sure you get the car warm, and then do the oil change yourself and allow time for it to drain completely. And as said just up a little bit, make sure you prefill the oil filter! But not too much as it will spill as you turn it on its side to get it on.

we are not all like that you know.
some of us actualy take pride in our work

i always drop my oil out after a long drive when the engine is nice and hot ... the oil runs better and cleans/drains out better. Never change the oil when it is cold and thick.