I want to change the engine and gearbox oil before I launch my car down the drag strip at the french car show. Can anyone tell me the engine and gearbox capacities please? Also, if there is any special gearbox oil recommended.
The capacities for a Murena 2.2 are 4.5 litres in the engine, and 1.6 litres in the transaxle. The engine definitely needs over four litres since our 'new' four litre oil pack is never enough - why did they change the can size from the original 5 litres which was ideal? The synthetic transaxle oil comes in 1 litre containers and 2 are more than sufficient to replace the oil in CX based transaxle.
I have always used synthetic oil in mine from new. Originally I used Mobil SHC which became Mobil 1 but now I use Castrol RS which is 10W/60 (mine are old packs as I believe they have changed the rating recently). The synthetic transaxle oil is 75W/90 and is even more expensive than engine oil, but easily worth it in the long run. However, the synthetics are much cheaper in France than the UK, so it is best to buy them when you are over there, and not pay the inflated UK prices.
As Anders pointed out, a low 'W' rating is fine, and the old terms thick or thin when talking about oil, cannot be used in relation to synthetic oil, since 'thickness' was to do with the waxy element in multigrade oils and which is not in synthetic oils.
We used to think a thick oil was better as all oils got thinner with temperature, and so if you started with a thin oil (better at cold temperatures) it became too thin at high temperatures to protect the engine properly. This line of reasoning was flawed, but particularly with regard to synthetics. In fact you need an oil that at cold temperatures can get around the engine quickly to protect it during the most vulnerable stage - almost all engine wear takes place when it is cold. However, you also need good protection when really hot.
A synthetic oil will fulfill both these extremes since it is fluid enough when cold to get around the engine very quickly, because it does not have the wax that makes multigrades thick and less fluid when cold. Yet it also has greater high temperature protection. A normal multigrade oil has lighter elements that evaporate or burn off with use, leaving the remaining oil even 'thicker' and worse from a protection point of view especially from cold. This is why it needs replacing often.
A synthetic oil will remain fluid at all temperatures throughout its life, which can be much longer too.
High mileage trucks often do 100,000 kms on one oil change! I have done 25,000 kms on one oil change in my Murena with no problems. It is time rather than just mileage that can determine when you need to change an oil, since it will depend on how much moisture has got in. If you do very low mileages, moisture will contaminate the oil during the long unused periods. So you need to change it. If you use the car regularly, the oil will stay cleaner and will not need to be changed as often. If the car is used regularly, and you use a synthetic oil, then two year change intervals can be fine. If you don't use it regularly then you might need to change it once or even twice a year.
Considering the cost of an oil change against the cost of an engine repair, it always amazes me that owners are often reluctant to change their oil, or use the best quality oil.
I hope this helps your understanding of an often mis-understood topic. Any further questions, please ask, and if I know, I'll give you my answer.