Hi all, I know there are plenty of threads re: best oil for your Cossie but I was hoping somebody out there could please advise me on the best way forward. I have a 4wd which has been tuned to around 300 bhp but was last put on the rollers in 2009 so not sure if power is still that from what was recorded back then. I do very few miles in her and most of the time she doesn't get treated harshly (general running around town and down the motorway cruising at a consistent speed) however for the last two oil services I was recommended Magnatec 5w30 a3/b4 and have obliged. The car seems to use about a litre every 800-1000 miles anyway and does gave a slight leak from around the dipstick but nothing major. Looking on the Castrol website it recommends 10w 40 Magnatec for standard spec, otherwise Edge (which of course is slightly more expensive). I appreciate Silkolene seems to be the favourite but I don't race the car and really cannot justify the cost. That said somebody else has recommended 5w 50 Millers which has a high zinc content, which I am told really benefits the engine. So the long story short is......will it be ok to continue to use Magnatec 5w30 or should I go for Millers or something else...hopefully somebody can suggest something that's around £30 for 4 litres?!? thanks in advance