Lubrication System In A Nova

[sTuDeNt]

Can someone explaine me something please!

I was thinking about it actually for a while now and it looks to me that there should not be a any problemes or issues of using different oils in a nova engine. Starting with 10w40 and going to further viscocities as long as we stick to the upper value of about 55 and varying lower leven it should only do good for an engine as the lower value is the cold vescocitie of an oil the higher the number the less friction it is in for cold eningine, taking in to the account it is winter now.
The other thing is what is the diference between synthetic, semi-synthetic and organic oils? (Apart from the fact that its different manufacturing process)

Thanks
Serge

[Aragorn]

the chemicals they are made from are different, im sure mineral is just the stuff that comes out the ground, semi synth is mineral plus some chemicals etc to prolong life and help it perform better in hard conditions and synth is made up entrirely of synthetic (ie man made) chemicals
might be wrong tho

as for the weights

vaux engines run on 40 weight oil when warm, the older cars are rated at 15w40 with the 15weight being when the engine is cold (and the oil is thicker) it acts like a 15 weight similarly with the 10w

that means u could happily run 10w 15w and possibly even 5w40 in any vaux engine without any problems

going upto a 50 weight oil in my opinion is silly, 20w50 and the like is just bad gunky shite

[m.d.]

if you run high viscosity oil there will be no problem running the car as an a to b, and on a car with warn rings its a good idea as it causes better compression, but if the car is to be reved high then a thinner oil is better. it causes less drag on moving parts such as the crank so allows free reving.