http://www.opieoils.co.uk/p-1280-oil...orsp27190.aspx

they recommend that for my 1.8 zetec engine would i be better off with a fully synthetic 5-30w or should i go for a 5-40w?

 

Although the piccie shows a 40 weight oil, it is most likely just a generic piccie and not the one you get as listed as a 30 weight oil.
tabetha

 

You want 5W-30 on a zetec or you will have a whole host of gayness.

 

10W40 has done no harm whatsoever in zetecs I have used it in, when supplied by other people.
tabetha

 

The early Zetecs suffered from sticky valve when not using 5W-30. Maybe okay on newer engines.

 

il go with the 5-30w.

 

Sticky valves were just that sticky valves, and were NOT caused by the oil despite what some say, they were caused by bad material selection on fords part.
I have a early 96 mondy always run on 10W/40, it has never not once suffered sticky valve, and from new.
The 40 and 30 refer to the thickness of the oil at temperature, NOT when cold which is when the valves used to stick, thuis if you run a 40 weight oil hot enough by thrashing the car, it's viscosity will be lowered to a level of a thinner oil such as a 30 weight.
This happens more so in the case of certain fully synthetics, (but I won't mention MOBIL!!), and they turn to water.
tabetha

 

sooo what should i go for!?

 

Either will do, if poodling around get a 30 weight but if you do give it some stick the viscosity(thickness) of the 40 weight will stay better instead of thinning out and losing oil pressure.
tabetha