What oil to buy now 10w 40 full syn Nulon is NLA?

[losh1971]

I'll also half admit I could be wrong as a quick look at other forums on Google it suggests what you're saying. I need to Do more sussing before I will say I was completely wrong.

Doesn't make sense that the 10w is 500mls per 10k and 5w is 1L.

 

[chrisp]

Doesn't make sense that the 10w is 500mls per 10k and 5w is 1L.

I wouldn‘t be too concerned or worried about either of those oil consumption rates. Both are well with in manufacturer’s tolerances, but yes, the lower consumption is preferable.

I think the thing to do is continue to monitor it, and if it significantly increases (say, beyond several litres per 10,000km), then consider doing the valve stem seals.

I stumbled across this nice write up on changing the valve stem seals on a LS engine (not the same as in the Commodore, but it’s still an LS). It’s something that I’d be doing if I was concerned about engine oil consumption. https://www.silveradosierra.com/thr...stem-seals-without-removing-the-heads.636338/

 

[Fu Manchu]

The King explaining oil viscosity and what the numbers and letters mean.

 

[losh1971]

Every oil thread on any forum… ever.

Well, this is embarrassing. I just checked my two bottles of oil and one is a 5w 30.

I watched that vid and it doesn't mention the 10w 40 being the same thickness as a 5w 40, but that it behaves the same as a 40 regardless of the W rating. So does that mean if oils were both 40 and you dropped in a ball at 100c the balls would fall at the same speed? Because why doesn't he just use the term thickness. I understand oil is not measured using that term. I'm still not convinced and will be asking the mech when next have some work done.


Also what I don't understand is why has there not been any full on fights and personal attacks thrown yet. Any good oil thread has to has some fighting words.

 

[J_D 2.0]

Well, this is embarrassing. I just checked my two bottles of oil and one is a 5w 30

Well that’s your problem then if you’ve been using a 30. A 30 weight is too thin IMO for an older engine and will burn a considerable amount of oil.

I know that was the case with my old SV6 which is why I changed it over to a 40 weight oil once it had about 150,000kms or so on it.

So does that mean if oils were both 40 and you dropped in a ball at 100c the balls would fall at the same speed?

Yes.

Because why doesn't he just use the term thickness.

Viscosity is the nerd term for thickness.

 

[chrisp]

Also what I don't understand is why has there not been any full on fights and personal attacks thrown yet. Any good oil thread has to has some fighting words.

You want some biffo? Let me post up the following expressions. They’re nothing to do with the topic of this thread, but from my experience, they often get things going…

”always use a torque wrench to do up the critical fasteners to the manufacturer’s recommendation”
”discard and replace the critical bolts and nuts the manufacturer says not to reuse”
and
“follow the instructions in the official service manual when in doubt”

There, that should get it going.

 

[VS 5.0]

I'm still not convinced

Coz you know more than a qualified mechanical engineer ?

 

[J_D 2.0]

“follow the instructions in the offical service manual when in doubt”

Official….ackchyually.

 

[Pollushon]

Different weights are different formulas. Oil weight is determined by bearing tolerances and different tolerances are different use cases. Stock engines tend to be tight, high performance tends to be loose. More film is less heat and counters expansion. Over time the bearings will wear and those tolerances will increase suggesting upping the weight

Detergents, shearing additives, dispersant and even carbon atoms per molecule can effect how the oil behaves over time. I'd wager your increased usage of one over another had nothing to do with the cold start rating and everything to do with the formula used to achieve that rating

 

[chrisp]

Official….ackchyually.

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Oops, I missed that one, but I did fix the other one!