Citroen XM Forum

2.0i and V6 is 10w-40 will yes.
I was sure the oil grade recommendation was changed in line with timing gear mods on the 24v but maybe im thinking of something else.

D

Don't underestimate the requirement for a thick oil in engines designed with greater clearances. A friend knocked a big end out in his BX-16v shortly after changing to Mobil 1.

Just checked.

Fpr the PRV-6 engines, Citroen specify 15w-50, other petrol engines, 10w40.

What is your source for that info Will and surely the difference cannot be that great, unless driven in an extreme climate as mentioned by Jan or generally thrashed about! Regards, Matthew T.

Interesting Mister Auto suggests 5W-40 for the PRV 12 and 24v! Regards, Matthew T.

And this site recommends 5W-40 and 15W-40! http://cararac.com/engine_oil/citroen/xm.html" onclick="window.open(this.href);return false; Regards, Matthew T.

The info is from the Citroen XM owners handbook.

In recent times many manufacturers have specified lighter weight engine oils for economy reasons. That doesn't mean it provides the sme level of protection.

oil viscosity will make a big difference to how the engine feels, thicker oil really smooths and silences them, even if you have no apparent noise, I have just serviced mine again, it had a follower tapping sometimes on a warm restart due to the huge amount of petrol that had got into the oil during my initial fumblings, changed the oil and filter with more 10w-40 and the engine sounds like new, 15w-50 would probably make it sound like a mute swimming in honey.

D

I tried thicker oils in my original 12v auto engine hoping to quieten down the tappets on cold starts, but there was not much difference tbh! Regards, Matthew T.

The info is from the Citroen XM owners handbook.

That is interesting Will as all mine say 10 W 30 or 15 W 40 (year round)!
Regards,
Matthew T.