What grade engine oil

[enyawbrown]

I have a '97 VR with the V6 engine...... I was reading the manual and it's kinda confusing determining the correct grade engine oil to use. Our outside temperature here in Jamaica is usually 20-22 degrees celsius........and IT LOOKS like it says in the manual where 20W-40 and 20W-50 can be used, but I'm not sure. Anyone knows what the outside temperature has to do with engine oil grade :speechles .......and the correct oil to use in my car :inquisiti

[bradc]

look for fully synthetic for a start, and I would recommend you go for as low as possible on the first number, it basically means how early the oil will start flowing and actually provide lubrication from the engine. I would suggest you try and find 5w30 or similar.

[pitslayer]

speak to don/amsoil on here(user name is amsoil) he should be able to tell you :)

[Nick Mann]

I think officially the grade is 5W40. In the UK people also use 0W30, but I will be changing back to 5W40 at the next oil change. The first number won't matter as much to you if it doesn't get cold over there - low numbers at the front give runny oil at low temperature. (Hows that for technical speak!!) I shouldn't imagine that the second number will want to be far from the 30-40 range, though, regardless of how hot it is where you are! Don't listen to me, though, as I ain't no expert!!

[enyawbrown]

well I spoke to someone here who owns a '98 VR-4 and he says I should use either 20W-40 or 20W-50........ the 5W and 10W would be too "runny" and thin for our local temperature......plus it's a HOT country so our oil takes not much time to get flowing /rally

[amsoil]

No thats not how it works. even a 0w at room temp will be thicker than a 50 when hot. so it wont be too thin, The only trade off is that thin costs money. It takes a bit of getting your head around but the 1st number is the flowability of the oil compared to a mineral oil when cold. So however your modern synthetic flows it will be given a grading as calculated from the old mineral oil days; of course this is essentially rubbish but does give some figures that people can use to compare like oils by. The trouble is that the oils arnt all alike.
All oils thin when they get hotter. The second number is the flowability when hot (100degrees) Mineral oils which are relatively impure, thin dramatically. Synthetic oils thin but not as much, therefore (and you will have to think about this one) the 'thin' 0w synthetic oil when it gets hot does not thin so much as the mineral oil would and so becomes numerically thicker, the scale having be created around mineral oils.
Multi grade mineral oils have VI's Viscosity Improvers added to not improve the thickness or flowability but to reduce the oils ability to thin when it gets hotter. Given that the outside ambient temperature makes little difference to the engines operating temperature going to a 50 grade would be crazy. The 5w-40 mentioned may well be right on the money and remember that the manufacturers specs given are always for the worst case scenario (ie using mineral oil) The film strength and hence protection given by modern synthetic oil is 3 to 5 times more anyway.

[bradc]

yeah what he said ^^^ ;)

[RugbyPete]

Havoline's a cheap but high performer for the money, best value I've seen.
Amsoil has the best specs regardless so any of their thresholds will give better scope for error selecting the correct oil. The euro spec 5w-40 should be ideal I would have thought, otherwsie stick with the trusty 5w30 Havoline if on a budget - the Energy version is semi-dino, but it has SO many modifiers, for the money its great. If you have the money go Amosil for 'The Best' money can buy if you need the reassurence.