5w30 engine oil for a VT

[Full Spectrum]

I dropped in mine Valvoline SynPower 10W-50 fully synthetic. Hardly touched a drop of oil. had it in for over 15,000km now. but i'm soon to replace the oil and see what it drops.. So i'd recommend that to anyone, and my car has around 160,000km+ now.

 

[vxcalais_01]

Easy, the compression ratio and oil pressures are well within or above the specs that are listed in the workshop manual,also theres no oil going through the engine when its being compression tested, the engine is only wound over a couple of times for each cylinder,its not running, therefore theres no oil pressure to squirt oil onto the cylinder walls to help seal the rings etc,so what oil is used in the engine doesnt come into it.Actually if the compression readings are low ,you can test for worn rings by squirting oil into the cylinder through the plug hole and seeing if the compression then comes up,if it does,the rings are worn,if it stays the same,its likely to be leaking /burnt valves.As an engine wears it slowly looses compression, and the hot and cold oil pressures drop.My readings have been around the same every time Ive done these tests, so this shows that over time, theres been bugger all wear occuring,it would show up on the tests otherwise.

Just to add to the conversation, oil pressure can be altered or affected in other words in engine oil by adding different additives/ elements, Sodium being one that comes to mind hehe

 

[vxcalais_01]

I dropped in mine Valvoline SynPower 10W-50 fully synthetic. Hardly touched a drop of oil. had it in for over 15,000km now. but i'm soon to replace the oil and see what it drops.. So i'd recommend that to anyone, and my car has around 160,000km+ now.

Synpower is an excellent oil.

An #w90 oil will definately be detrimental to the engine. It wont cease up or anything, just it will wear at a fast rate and possibly effect seals over a period of time compared to a thinner one. The oil being a w90 at operating, a 5w oil at startup would still have been thicker than it for a period of time, until it thinned out being a w30/40/50 at operating.

The problem is mainly trying to make a stable W90 oil as it would need an abundance of visc modifiers etc.

 

[Brett_jjj]

You wouldnt go that much over the specified oil type anyway..5 or 10 is heaps.Like the specified oil is 20W-50 for my VSV6.I use an oil thats 10 over and 5 under the specified range,a 15W-60 oil,which is penrite HPR15.Its semi synthetic and Ive not had a problem with it yet.I used to use castrol GTX2 for years,in all my V8's and even the first couple of oil changes I did to my VS when I first got it.I then switched to the penrite because it offered a bit better protection,was semi-synthetic,and was still relatively cheap to buy compared to normal oil like GTX2.
Heres what the back of the oil bottle says about the HPR15 oil.
"Penrites EXTRA 10 provides your car with superior protection.The extra 10 in the second number of the SAE rating means the oil will not thin out as quickly as lower rated oils,providing a better class of protection for your car at operating temperature."
It goes on to say"Ideal for conventional,turbocharged,and supercharged petrol engines. where SAE 20W-50 ,15W-40 and 15W-50 grades are specified in the owners handbook."

 

[torch]

Interestingly, visiting the Mobil, Shell, Castrol and Penrite australian oil sites, the overall recommended oil for the vt v6 was the 10W/30. Penrite also suggested up to xW/50 grade as their highest, but no 60 recommendation. The castrol site also listed its 5W30 syn as a recommendation, the original query in the thread. Overall oil companies are very guarded with their recommendations and dont want to be sued/taken if they provide misleading information, however, I do realise that perhaps they are covering themselves by just stating that is what the manufacturer says should be in it.

None of the sites tell us that if the motor has 150 000km+ on it that you must switch to a heavier oil, no one suggests that older engines that come with a 20w/50 recommendation should change to say a 25W/70 oil after 150000km. Why the contrast with the v6?

I could understand the advice that if the car is burning oil or showing low oil pressure, that a change is necessary, but otherwise, I dont see the logic.

 

[Brett_jjj]

I only use it because as I previously said,I use my car at full throttle a lot of the time,and it gets driven very hard.Definitely not how the average driver ever drives,so I wanted a little bit better protection at high temp /high revs than the standard oil, so I chose the slightly thicker at high temps 15W-60.Id love to use a full synthetic oil like mobil 1, but it gets too expensive as I always change my oil and filter every 5000 k's.

 

[lufkin]

Id love to use a full synthetic oil like mobil 1.

this is what i got recommended and bought, it was $89 lol

 

[showbags]

persoally ik wouldn'y use anything thinner than a 15w40 or 15w50 in a VT. the dealer reccomendations are for a brand new engine not something that has done a couple of hundred thousand kilometres. I'm not going to go into the science of oil viscosity( i worked in the industry for 8 years), but it's all to do with bearing clearances not oil gallery sizes. some of the current model alfa's specify a 0w60 non phosphate engine oil, now if you use anything else the engine will expire very quickly.(one dealer used 0w30 because they ran out of 0w60 and the engine grenaded after 5600km from bearing failure- the customer was 70 years old so the vehicle wasnt thrashed).these engines are the 3.6 global engine which are variants of vz-ve engines. some of the current low emission deisels(european) will shut down and cannot be re-started if you put the wrong grade of oil in it. change the oil, if it rattles, go one grade thicker. buick v6's are very forgiving unlike a lot of others.

 

[torch]

persoally ik wouldn'y use anything thinner than a 15w40 or 15w50 in a VT. the dealer reccomendations are for a brand new engine not something that has done a couple of hundred thousand kilometres. I'm not going to go into the science of oil viscosity( i worked in the industry for 8 years), but it's all to do with bearing clearances not oil gallery sizes. some of the current model alfa's specify a 0w60 non phosphate engine oil, now if you use anything else the engine will expire very quickly.(one dealer used 0w30 because they ran out of 0w60 and the engine grenaded after 5600km from bearing failure- the customer was 70 years old so the vehicle wasnt thrashed).these engines are the 3.6 global engine which are variants of vz-ve engines. some of the current low emission deisels(european) will shut down and cannot be re-started if you put the wrong grade of oil in it. change the oil, if it rattles, go one grade thicker. buick v6's are very forgiving unlike a lot of others.

I appreciate the point that the manufacturers specs are for when the engines are new, however, as I pointed out earlier we dont go putting 25W/70 oil into engines originally designed for 20W/50 engines after a 150000km unless there is something wrong with it, why the difference with the v6.

I also understand the bearing clearances will increase with wear, how exactly will using the original spec viscosity oil here cause problems, the oil will flow faster? is that a problem?

 

[graham7773]

+1 for torch. Holden employs university trained people with all sorts of degrees and qualifications in everything car related. From new the VT V6 and VT V8 engine oil specifications were for 50 year old design, cast iron clunkers that needed said oil specs (20w50) and ran well on them. I have seen 5L V8s with 400.000ks on them, a bit tired but no smoke or undue noise from them. My V6 is running 20w50 at 220.000 with only timing chain noise, no smoke or other ugliness. Put low spec oil (5 or 10w 30) in? No way. Would probably sound like some little gremlin in the motor with an fbh smashing everything he could reach. A mechanic who worked on my motor said it is one of the best sounding motors he has heard. My vote is for standard spec oil. It does the job well. Just by the way, as bearings wear and clearances widen, the oil does flow faster, out of the wider clearances = loss of oil pressure. Might not be an advantage.