A&Q about 350Z
Q:
i was on this site and asked for an oil recommendation, here is the reply.
Mathew,
Thanks for the mail.
For the Golf the 10w-40 semi is fine, you could if you wanted to move up to a
5w-40 full synthetic, there will be no issues i doing this and you will get
longer drain intervals, less wear etc.
Have a look at Motul, Fuchs and Silkolene.
Regards
Guy.
Opie Oils
anyone gone for a 5-40 fully synth before? i take it it will be thinner? mine leaks enough as it is.... may try it tho :P
Synta Gold is 5w40, used this for last 2 years and before that Mobil and Castrol 0w40
A:
Errrrrr.....................................
fight!!!!!!!!!!!!!
ROFPMSL
Sorry couldn't resist
A:
An engine would be "starved of oil" only because its flowed down (gradually over time, due to its viscosity) the upper surfaces back to the sump, after last time it was run hot. And, since 5W/40 and 15W/40 are the same viscosity when hot, they'd have flowed down the same. So there is no advantage here.
Perhaps there is a small effect if you ran a car for a few minutes, then switched it off for an hour, then ran it for another few minutes, etc. But the main damage here is 'cold start corrosion' which relates to exhaust gases, not really the oil problem. So its good advice if you switch on your car just to move it, to actually leave it running for 10 minutes and let it warm up. This heats up the exhaust and thus prevents water building up in here, which corrodes it. But I digress...
Yes, they both flow down the same. But a thinner oil pumps up faster than a thick one, hence the advantage.
A:
5W/40 oil is thicker when its cold, than 15W/40 when its warm. So its okay to use.
so......... a 5W/40 will be thicker when cold (rating of 5 cold) than a 15W/40 (rating of 40 when hot) no sh*t Sherlock but not for the reasons you thought tho
A:
A gentlemanly discussion about the finer points of tribology and engine technology, if you will.......
Errrrrr.....................................
fight!!!!!!!!!!!!!
ROFPMSL
Sorry couldn't resist
A:
so......... a 5W/40 will be thicker when cold (rating of 5 cold) than a 15W/40 (rating of 40 when hot) no sh*t Sherlock but not for the reasons you thought tho
You tell me the reason I thought so and I'll tell you if what you're thinking is right! I just said it from the beginning, for no other reason than its true.
A:
looks like i missed the fun lol
would i therefore gain anything by going fully synth? sounds like ill get protection slightly sooner after start up, i guess itll warm up faster too.
what are the differences, protection wise between semi and full synth?
A:
Not a huge amount, on your engine - it'd be different if you were running huge turbo power. TBH if you change your oil often, you'll probably spend more on oil than a secondhand engine would cost you after a couple of years!
A:
I personally wouldn't use any oil less than a 10w in an older higher mileage engine. It's all very well haveing an oil that gets around the engine quickly when cold, but if your'e engine has done loads of miles then it is going to be pretty slack and using an oil that is really thin when cold is just going to cause high oil consumpsion.
A good quality semi-synthetic oil is fine for most engines unless, as mentioned before you are running a turbo, or any high spec engine(but just to piont out fully synthetic should not be used for running in).
A:
they were my thoughts also, hence i wasnt too sure on the recommendation.
i think ill stick to my millers semi synth. its due a change soon, i need to order a proper 16v sump plug.
about £8 from the stealer. such an annoying expense, has to be done tho.
just want it cheap and asap!
A:
... TBH if you change your oil often, you'll probably spend more on oil than a secondhand engine would cost you after a couple of years!
A:
Agree! So long as its not thinner than the equivalent hot oil viscosity for the manufacturer's recommendation.
It's the cold viscosity you need to worry about! especially on high mileage engines, sometimes (always above 200K IMO) even the manufacturers recomendation is too thin. 40 is always OK when hot, it's the 10w and 5w in the first few sec's which give the prob's IM(limited)experience.
A:
A bit rough on the new lad TSC!!
Its not what you say sometimes its how you say it (I now know just to ignore you)!!
Anyway, whats the best oil for my Mk1 1.8 8v with 196K on the clock??
A:
I'm abrupt.
Don't use oil, use bearing grease. It slops around so much less in the corners than a 20/50 would........
A:
Cheers for that TSC!!
Anyone got any PROPER answers!!
A:
Personally, after reading TSC's recommendations I now blend my own oil from a secret proportion of fish oil, filtered puppy seal blubber and stolen Johnson's baby oil. The puppy seal blubber has a naturally high protein content which is thixotropic and also has excellent viscosity modifying properties. And the baby oil makes the engine bay smell sweet too.
No but seriously, for a 1.8GTI just use 10W/40 semi-synth and keep on top of the changes. I always use oil flush when I do a change too, this is probably going to start another debate....
A:
I would personally be using a 0W40, that way your oil is as thin as possible when cold and then thins out to the correct thickness at running temp!
A:
10W 40 semi-synth is best for a MK2 GTi, even VW agree!
Thinner (fully synth oils) are designed for more complex and newer engines. Thin oil is specifically used for cars with turbo's etc (among other things, but mainly high performance) as the oil ways are not as wide!
However I would not advise running your 1.8T on 0W30 or 5W40 as the oil is so thin it tends to run past the turbo seals into the exhaust system, causing the turbo to run a bit dry! lol.
Either way. Stick with 10W40 Semi and change it every 6K!
A:
10W 40 semi-synth is best for a MK2 GTi, even VW agree!
Thinner (fully synth oils) are designed for more complex and newer engines. Thin oil is specifically used for cars with turbo's etc (among other things, but mainly high performance) as the oil ways are not as wide!
However I would not advise running your 1.8T on 0W30 or 5W40 as the oil is so thin it tends to run past the turbo seals into the exhaust system, causing the turbo to run a bit dry! lol.
Either way. Stick with 10W40 Semi and change it every 6K!
How on earth is 5W40 any thinner (at operating temps) than 10W40???!!!!
A:
The rise of synthetic oils has as much to do with manufacturers wanting to extend service intervals, as the day-to-day performance of the oil. A modern car typically gets serviced by the main dealer, and many manufacturers have a "service included" type of scheme. Also long service intervals are a selling point.
An older VW, owned and maintained by an enthusiast, is serviced much more regularly and so this advantage of the synth doesn't have so much value. So, a semi-synth changed frequently, performs better than a synth changed less frequently. A synth changed frequently is better still, but the gains are tiny compared to the extra cost incurred.
A:
How on earth is 5W40 any thinner (at operating temps) than 10W40???!!!!
Its not the op temp thats the problem, its when cold that it causes problems with the seals, especially with 0W30 stuff!
A:
Its not the op temp thats the problem, its when cold that it causes problems with the seals, especially with 0W30 stuff!
doesn't sound right
manufacturs specifically suggest lower vicosity "cold" figure oils for turbo engines:
A) because they are often fully synthetic and don't have the same problems "coking up" in the oil galleys, that is not doing a cheeky line at a party, but when your mineral oil "burns" due to the extreme temperature in your turbo having just popped down the shops, spinning the wheels all the way and you turned the engine off with the turbo glowing red like your mums lava lamp.
B) the lower viscocity reduces the period that the bearing has no oil pressure on start up.
if its getting by your turbo oil seals at engine start up, you need a new turbo anyway
A:
dear me Paul
A:
dear me Paul
Your point being?
A:
Maybe it's this.....
A modern car typically gets serviced by the mail dealer
I've never seen my postie under my car changing the oil........