Which type of engine oil is best?

[serialk11r]

Instead of getting Pennzoil Ultra you can just get their new Platinum or Platinum Ultra at Walmart, I got a 5 quart jug for 25 bucks. It's the Fischer Tropsch GTL base one.

Speaking of which I need to get an oil change.

[Fingie]

UAPC runs on the cheapest (synthetic) crap i can find on sales in our hardware stores. The engine design is 40 years old so it isn't so picky.

Bought Champion 10w-40

[Fingie]

i should try some new oil

what'd you recommend?

[101Volts]

I'm surprised nobody mentioned this: Not all 0w30s, 5w30s and 10w30s are the exact same viscosity, the numbers represent viscosity ranges. Pennzoil Platinum 5w30 is thinner when hot and cold than Mobil 1 0w30, you have to compare oil data sheets which are public to know things like this.

M1 0w30:

Viscosity @ 100ºC, cSt (ASTM D445) 10.9
Viscosity, @ 40ºC, cSt (ASTM D445) 62.9

PP 5w30:

Viscosity @ 100ºC, cSt (ASTM D445) 10.3
Viscosity, @ 40ºC, cSt (ASTM D445) 56.9

[Stubby79]

Originally Posted by Fingie

i should try some new oil

what'd you recommend?

I'd think you have totally different brands there over the pond. You tell us what you have access to...

[101Volts]

Originally Posted by Fingie

i should try some new oil

what'd you recommend?

It depends on your application. Among Ecomodders the idea is to use 0w40 over 10w40 for example but see my reply above. On a related note if you have fuel dilution in that 40 year old engine 10w40 isn't horrible.

Also, maybe you don't have "oil stabilizers" in Finland but if you do stay away form them; they're useless in well-working engines, they can wreck havoc in cars requiring 0w20 and the common STP and Lucas "Oil Treatments" thicken your oil and make the engine less fuel efficient possibly with exception if your engine's oil is already too thin for operating conditions. "Oil Stabilizers" change the oil's chemistry and in cases of pure synthetic oils like Amsoil they would reduce the oil's life.

Originally Posted by Stubby79

I'd think you have totally different brands there over the pond. You tell us what you have access to...

I agree.

[Fingie]

the design is 40 yrs old, and the the engine is only driven 40k miles doesn't consume oil yet and it's not even badly coloured yet

stock oil recommendation is 10w-30 and 10w-40, also 5W-40.

available brands:
Mobil/Shell/Castrol/Liqui Moly/Toyota-brand oil/Gm genuine/GMN longlife/Motul/Red Line/Ford Formula

[ThermionicScott]

Originally Posted by 101Volts

I'm surprised nobody mentioned this: Not all 0w30s, 5w30s and 10w30s are the exact same viscosity, the numbers represent viscosity ranges. Pennzoil Platinum 5w30 is thinner when hot and cold than Mobil 1 0w30, you have to compare oil data sheets which are public to know things like this.

M1 0w30:

Viscosity @ 100ºC, cSt (ASTM D445) 10.9
Viscosity, @ 40ºC, cSt (ASTM D445) 62.9

PP 5w30:

Viscosity @ 100ºC, cSt (ASTM D445) 10.3
Viscosity, @ 40ºC, cSt (ASTM D445) 56.9

You're confusing the "warm" viscosity (40°C = 104°F) measure with the actual "cold" viscosity used to determine the first number in the viscosity rating. The 0W or 5W or 10W is measured at -30°C or below.

[Ecky]

There's a lot more going on than just viscosity, but it's certainly an important number. I've spent a fair amount of time over in Bobistheoilguy reading, and the conclusion I've come to is that with the oil change intervals most use, most oils will offer more than adequate protection that any lubrication-related wear will not be what does the engine in. Many synthetic oils would probably be good for 20-30k mile changes, while manufacturers are still often recommending 7500-10k changes, and many owners are still changing at 3-5k.

Right now I'm running Honda Green Oil in my Insight, which is significantly thinner than commercially available 0w16's when cold, and somewhere between a 16 and 20 weight when hot. In Japan, Honda specifies "NEXT" oil for their hybrids and Earthdreams engines, which makes a 0w16 look really thick by comparison. I'll do an oil analysis when it's​ time for a change.

[SH@UN]

All oil threads should be titled "can of worms".