Originally Posted by Dave Henshall

far too thick IMO....

i used to run castrol rs 10W60 in the escos. after a good blast, sitting at idle at a set of lights the oil pressurte light would flicker on and the oil pressure on the gauage was next to nothing, a small blip on the throttle and it would come up bu the engine did sound like a bag of spanners.

after taking some good advice from on here from oilman, i put in some fully synthetic silkolene 5W40 (too thin i hear you cry!!!) but believe it or not, after the same run, the silkolene held better oil pressure and the engine was much quieter, not only after a run, but from cold aswell. unless i'd seen this with my own eyes i'd have not believed it.

its to do with how the law changed on the marketing of 'fully synthetic' oil, they are now allowed to call some oil fully synthetic even though it has some mineral content in it, there is a % limit that they are allowedto blend in (for cost effectiveness) and still call it fully syn. the silkolene is 100% fully syn, as as such is priced acordingly. amazingly aswell though, since switching to the silkolene, i had to top up my oil less that i used to when running the castrol RS.