Thin oil not such a good idea.

[Ton-up]

My VW T5.1 2010 is now just shy of 250,000 miles and although runs fine, I wonder if I should go up an oil thickness from now on.

 

[Domdom]

Why would you? Whatever you’ve been doing has got you to 250k miles so why change the spec now?

 

[Ubique]

No.

 

[premmington]

No.

Thats a "NO" from me as well...

 

[atomant48]

in 2001 ish the design of the mazda rx8 was nearing completion. the designers were tasked in formulating a specification for the oil. after a rather long period of research and development the engineers decided on a mineral 10w40. 15w 40 in warmer climates. this was passed to the higher ups in mazda, who kicked it back, and said no, emissions are affected by such a thick oil, do better.

mazda finally settled on 5w40. the result of which the primary failure mode on correctly serviced cars was rear stationary bearing failure (this is discounting cars what had early failure because of abuse and neglect)

otoh, most specialists, myself included, and most engine builders specify 10w40, as the original engineers did. i have seen engines that have been run on 10w40 go 140k miles with no appreciable bearing wear. go figure.

Sounds about right. We used to add 2 stroke into the tank on earlier RX variants … probably along the same lines. Also I’m not sure anyone running a rotary is thinking about emissions too hard - Mazda should have got an exemption against the rules simply because they are cool !

 

[Bornfree]

I’ve always hated stop/start, especially on turbocharged engines. Whoever thought that was a good idea? Car on a drive, up to temperature, turbo working away merrily, and then you come to a junction. The engine stops and oil pressure is lost. Such a nice way to treat a turbocharger, don’t you think?
Oil isn’t just lubricating the turbo, it’s cooling it as well so you get burnt oil accumulating in the turbocharger oil ways.
I just map it out. Button does nothing, problem solved.

As for other engine component life, there are so many problems which oil can’t fix. Manufacturing tolerances, the fad for tabless bearing shells, small sump capacities, long oil change intervals, weak timing chains, wet belts, and cheap oil filters to name but a few.

And as for this “Long-Life” oil, Pah! That just means the additives should keep it in spec for longer, it does not mean the oil is somehow miraculously staying clean. It’s still picking up all the junk and carrying it around the engine for longer causing more premature wear. Evidence of this is plentiful in the USA where bypass oil filter kits are quite common, and where they are fitted, it’s not unusual to see 500k miles with little discernible wear.

Most turbo engines with stop start have water cooled turbos with an electric pump that runs on after the engine has stopped.

 

[Gareth J]

Considering the general trend towards engine reliability and longevity alongside performance, economy and cost, I wouldn't be too quick to knock engine development.

Early road vehicles were expected to see oil changes every few hundred miles with a lifespan of a few 10s of thousands of miles. All while giving performance of 10s of bhp/l

Mid century cars had improved on that with better performance, service intervals measured in 1000s of miles and engines built with relatively simple rebuilds in mind at several 10s of thousands.

Early 2000s cars saw service intervals often exceeding the lifespan of the first combustion engined vehicles often with engines outliving the rest of the car at ~200,000mi all while delivering 150+bhp/l

Very modern engine designers appear to be struggling to make recent developments reliable under real world conditions. But I suspect that the overall trend of improvements will be followed in the end.

 

[AVI_8]

Most turbo engines with stop start have water cooled turbos with an electric pump that runs on after the engine has stopped.

But the oil pressure goes to zero when the engine is stopped and takes a second to rise when the engine is re-started, that’s when most of the bearing wear takes place.
Stop/Start is for government emissions criteria nothing else, I switch mine off as soon as I’ve started the engine every time.

 

[GRW]

Neither the generator handbook or the engine handbook give a spec, just "use 15W-40 oil"

If its a generator small engine, it's not likely to be anything exotic - probably an ordinary mineral oil.
It'll bring a very small amount and an air-cooled engine? If so the oil gets a hard time (& the motor spins up instantly to relatively high rpms on most).
3000rpm? Oil change at 100 hour intervals max I expect, but change at 50-hours better.

 

[Domdom]

Considering the general trend towards engine reliability and longevity alongside performance, economy and cost, I wouldn't be too quick to knock engine development.

Early road vehicles were expected to see oil changes every few hundred miles with a lifespan of a few 10s of thousands of miles. All while giving performance of 10s of bhp/l

Mid century cars had improved on that with better performance, service intervals measured in 1000s of miles and engines built with relatively simple rebuilds in mind at several 10s of thousands.

Early 2000s cars saw service intervals often exceeding the lifespan of the first combustion engined vehicles often with engines outliving the rest of the car at ~200,000mi all while delivering 150+bhp/l

Very modern engine designers appear to be struggling to make recent developments reliable under real world conditions. But I suspect that the overall trend of improvements will be followed in the end.

Early and older cars didn’t even have oil filters. Manufacturing tolerances could be measured with a yardstick and it was all done by operators, hence the huge discrepancies.

By the 60’s and 70’s things moved on. Stuff was mass produced by machines although nowhere near the automation levels we have today. But the one thing which hadn’t moved on was oil. You had a choice, Castrol or Duckhams, both 20/50. Ok, slight exaggeration but it was considered in general that oil was oil, and synthetic was unheard of.

By the early 2000’s we had much better lubricants and higher levels of automation in manufacturing.

Are you seeing the trend here? Better build and better lubricants…….

So now we had stuff that was well made and reliable. Good. And like all good things, someone felt the need to improve matters. Erm, improve? That’s a subjective viewpoint. How does one improve the VAG 1.9pd engine? The only thing would be to clean it up a bit, but here you have an engine that’s good for 500k miles without a lot of work beyond routine maintenance. Compare that to, say, JLR Ingenium or Ford Ecoboost. No contest.

The list of improvements seemed to centre around reducing weight, whilst, I would point out, much more weight was being added in other areas like reducing NVH, soundproofing and so on. Camshafts are often now hollow with pressed on lobes, timing chains thinner than a bicycle chain, cam belts running in oil, filthy oil at that, reduced sump capacities to save the 1kg of oil, and so on.

My point? Oil is almost everything. The smaller the sump, the more often it needs to be changed. Forget manufacturers claims about 20k intervals, that’s so they can show a lower TCO on the sales blurb. My rule of thumb is 1000 miles per litre of oil in the engine. As for the rest of the problems, they won’t go away until engine manufacturers start making them properly again. Nothing can mitigate a necklace sized timing chain except a chain that’s fit for purpose, I.e.thicker and heavier, double links even like the older Mercs. Same thing for all those other “improvements” - stop building disposable junk.

 

[steveo3002]

doesnt help that its considered normal /fine for a new car to use a litre of oil per 1000miles , average joe wont lower themselves to open the bonnect unless forced to so thousands of cars running about with no oil in them

got just shy of 250k on our petrol focus , never opened , went up to 5/40 somewhere along the line because it used a bit , try and change the oil around 6k and its never been ran low on oil

 

[Craig-SM]

5w30 oil with annual service, does less than 8k per year, currently around 170k miles and no issues. I’ll keep with the oil spec and routine

 

[Robotstar5]

If its a generator small engine, it's not likely to be anything exotic - probably an ordinary mineral oil.
It'll bring a very small amount and an air-cooled engine? If so the oil gets a hard time (& the motor spins up instantly to relatively high rpms on most).
3000rpm? Oil change at 100 hour intervals max I expect, but change at 50-hours better.

I do keep an eye on the hour meter for oil changes, the previous genny was 100 hour intervals and did over 700 hours before the electronics died, I will try the 50 hour changes on this one

 

[Guineafowl]

LR Time on YouTube are advocates of 10/40 in Discovery 3 and 4s

They use 5W40, instead of the recommended 5W30 (or, 5W-‘dumbass’, as they call it )

He’s kept the big end bearings from all the rebuilds, with details recorded on them, and it does seem that the 5W40 engines have less wear. Small sample size, though.

I was thinking of upping the oil viscosity for the wife’s petrol V40 from 0W20. Wasn’t sure which number to increase. Perhaps better to change the oil twice yearly instead of once?

 

[Kayos]

They use 5W40, instead of the recommended 5W30 (or, 5W-‘dumbass’, as they call it )

He’s kept the big end bearings from all the rebuilds, with details recorded on them, and it does seem that the 5W40 engines have less wear. Small sample size, though.

I was thinking of upping the oil viscosity for the wife’s petrol V40 from 0W20. Wasn’t sure which number to increase. Perhaps better to change the oil twice yearly instead of once?

I knew it was 40, just got the 10 wrong

It is a small sample but very methodical (and German)

 

[GRW]

I do keep an eye on the hour meter for oil changes, the previous genny was 100 hour intervals and did over 700 hours before the electronics died, I will try the 50 hour changes on this one

What genset engine is it? Chinesium or not? Petrol or diesel?
(I'd seriously consider a Honda GX petrol engine with LPG conversion over ANY of the Chinesium diesels. Rated as a 1000 hour engine by Honda - I saw loads that did MUCH more than that. Key with LPG is keep them from running hot so very good ventilation/airflow - and mai tain a decent, smaller than stock spark plug gap.... its the only way to retard ignition for gas, & stop you burning out exhaust valves).

A petrol set is way less than a decent 3000rpm diesel with a Yanmar in it, & on lpg the running cost is comparable as well. Only bugbear is manual start is harder than on petrol - but leccy start ones no bother.

 

[Robotstar5]

What genset engine is it? Chinesium or not? Petrol or diesel?
(I'd seriously consider a Honda GX petrol engine with LPG conversion over ANY of the Chinesium diesels. Rated as a 1000 hour engine by Honda - I saw loads that did MUCH more than that. Key with LPG is keep them from running hot so very good ventilation/airflow - and mai tain a decent, smaller than stock spark plug gap.... its the only way to retard ignition for gas, & stop you burning out exhaust valves).

A petrol set is way less than a decent 3000rpm diesel with a Yanmar in it, & on lpg the running cost is comparable as well. Only bugbear is manual start is harder than on petrol - but leccy start ones no bother.

I'll PM you to save cluttering up the oil thread

 

[pedrobedro]

The Vitara 1.6 says to use 0-20 oil so that's what I put in it. It's not cheap stuff though.

 

[PhillipM]

in 2001 ish the design of the mazda rx8 was nearing completion. the designers were tasked in formulating a specification for the oil. after a rather long period of research and development the engineers decided on a mineral 10w40. 15w 40 in warmer climates. this was passed to the higher ups in mazda, who kicked it back, and said no, emissions are affected by such a thick oil, do better.

mazda finally settled on 5w40. the result of which the primary failure mode on correctly serviced cars was rear stationary bearing failure (this is discounting cars what had early failure because of abuse and neglect)

otoh, most specialists, myself included, and most engine builders specify 10w40, as the original engineers did. i have seen engines that have been run on 10w40 go 140k miles with no appreciable bearing wear. go figure.

I used to run the race motors on 0w30, no issues. In fact RotaryRevs when they first started going had some of my old motors and Ben was amazed at the condition of the bearings and there still being oil film everywhere. They even used that to recommend the same oil for track and race cars they did the engines for at the time.
The biggest problem was not the viscosity, it's fuel dilution, and not using full synthetics because of the OMP.

Delete the OMP and switch to fully synth and I wouldn't even have a problem with 0w20 on new bearings tbfh, they're massive on an '8, you're almost always in full hydrodynamic outside of idle, and the clearances are small relative to the size. Plus your bypassing a lot less of the oil flow when cold compared to a 10-40.