grade engine oil

[splitpin]

It was most definitely semi synth for £10 for 5litres

Yep, 5/30 semi synth in our Asda at a tenner a tub or you can have 10/40 Diesel mineral for same price, offer been on for last couple of weeks.

[scanner]

What the numbers mean and what W means................

When you see a W on a viscosity rating it means that this oil viscosity has been tested at a Colder temperature. The numbers without the W are all tested at 210° F or 100° C which is considered an approximation of engine operating temperature. In other words, a SAE 30 motor oil is the same viscosity as a 10w-30 or 5W-30 at 210° (100° C). The difference is when the viscosity is tested at a much colder temperature. For example, a 5W-30 motor oil performs like a SAE 5 motor oil would perform at the cold temperature specified, but still has the SAE 30 viscosity at 210° F (100° C) which is engine operating temperature. This allows the engine to get quick oil flow when it is started cold verses dry running until lubricant either warms up sufficiently or is finally forced through the engine oil system. The advantages of a low W viscosity number is obvious. The quicker the oil flows cold, the less dry running. Less dry running means much less engine wear.

[nfn]

A few years ago I did an experiment with ten or so brands and viscosities of oil -- some of it was left by a previous tenant where we were living, and the rest of it was left over from various oil changes on my cars. I got the idea from reading someone else's forum post. What I did was measure out 100ml of each after the containers sat in a cold garage in winter, then timed how long it took for each to pass the 100ml through a very small funnel. One of them was an expensive 0W/something, and it flowed much better than the others. Of the rest, there was a difference between brands, with good name-brand/major oil company brands flowing faster than the cheap stuff -- cheap 5W/ didn't flow as fast as Valvolene 10W/. I decided to always go for more expensive oil on the basis of this, but it's probably not a great test, as free flowing through a funnel might not be the same as being pumped in an engine...

[Northern Bongolow]

the proper oil test that are done to define an oils spec are not a million miles from your tests,so it would be quite acurate.

[M 80NGO]

I used halfrauds own 5-30 semi synth today as thats whats listed for the ford ranger 2.5 td