Oil extraction through dipstick tube on 3.0 HDi 240 (DT20C) – anyone doing it?

[Xeper]

Hi all,
I have a question for fellow C5 X7 3.0 HDi 240 (DT20C) owners.

Does anyone perform oil changes by extracting the oil through the dipstick tube instead of draining it through the sump plug?

I'm mainly interested in real-world experience:
How much oil can actually be extracted?
Has anyone compared the extracted volume with the amount remaining after removing the drain plug?
Does the dipstick tube reach the lowest point of the oil pan on the DT20C?
Is there a significant amount of old oil left behind?

Current vehicle status:
Citroën C5 X7 3.0 HDi 240
~210,000 km
oil changes every 10,000 km / 1 year
always using MANN or Purflux oil filters

If anyone has done a direct comparison:
Extract oil through the dipstick tube,
Measure the extracted volume,
Then remove the drain plug to see what's left,

I'd be very interested in the results.

Thanks in advance!

[mickthemaverick]

It is generally accepted with most engines that you do not get a full extraction so stick with the drain plug and do it properly:

[Steve Walsh]

Mick is correct, I worked as a Marine engineer for many years and the only way on many engines was extraction method, When the engines needed overhaul it was surprising how much sludge etc was in the sump..
Always drain from sump, When hot after a decent run, Use good quality oil and you wont have any problems due to dirt in oil

[Xeper]

Sure, I agree that draining from the sump is beneficial.

However, for some reasons, legit draining may be difficult for me, and my priority is to have 10k/1Y OCI in my 3.0 HDI.
As the car is still new to me, Im just wondering has anyone extracted oil from the dipstick in HDI240 and how much oil remains in the sump.