Mobil1 5W30

[luvpsi]

hey guys i have done a bit of research in the goods on oils thread however no answer on what im after.

i work at a HSV dealership and can get my hands on Mobil1 fully synthetic 5w30 oil. will this be suitable for my rb25det with roughly 100 000kms and a stock turbo

[SiR_RB]

if u can get it for free, then good ! but if your gonna pay for it i would go for something abit thicker like 10w-40 etc

[luvpsi]

yeah i get it for free but i was worried about it being a little to thin most people seem to use 5w50 from mobil1 but we dont use that here in our HSVs

[discopotato03]

I put a bit of searching into locally available Mobil 1 oils and most seem to think the current M1 0W30 and 5W30 oils are "Green" oil because their formulation was changeed a few years ago .

Long story short , a very effective anti wear agent in oill is Zinc Di Alkyldithiophospate (ZDDP) but the eco Nazis have convinced the authorities that in higher concentrations eventually poisons Cat converters reducing their effectiveness .

Probably the engine components that work oil the hardest are the valve train ones and generally its the interface between the cam lobes and rockers or buckets . "old school" iron V8s need heavy valve springs to push valve crash or bounce further up the scale when you want to rev the things higher and higher . Because in these engines the valve springs are trying to control the innertia in the followers/push rods/rockers/caps/valves when you use high poundage springs they exert really high point contact loadings on the followers and cam lobes . If you run "Eco oils" in these old dinosaurs they destroy the buckets/lobes/rockers in short order .

Now , what the General doesn't usually tell people is that virtually all late pushrod engines have roller cam followers so the contact loadings/friction/effective anti ware oil additives are not as critical as they once were .

Four valves per cylinder DOHC engines are generally more forgiving because their valves are smaller and lighter and don't need high spring rates to stop the valves rebounding off their seats to reasonably high revs ie 7 .

Now I don't think an RB25DET driven with a bit of sympathy is overly hard on its oil provided it and the filter is changed regularly . If you push it hard enough to get it pretty hot then any 30 weight oil is a bit marginal IMO .

Really only you can decide if cost vs reliability is the priority though I don't .

I get back to this later , cheers A . `

[tricstar]

I can't believe HSV's run 5w30, ( my bro's got a series2 malloo ) and that thing runs day in day out @ 110-130 degrees and at the track I've seen it 150+ and thats with a massive oil cooler and 8L of oil, what is the deal with those things??

which dealership do you work at, your probably seen it, or worked it, spent more time in the shop than on the road

anyway, on the oil, I used 5w40 mobil1 in for a while, did a one day motorkana, at the end of the day had no oil left in the motor ( well just enough to run, didn't register on the dip stick ) just too thin....

now use Nulon 15w50 no such problems I'm sure I don't have the same clearances as a factory motor, but that was my experience.

[MrStabby]

I can't believe HSV's run 5w30, ( my bro's got a series2 malloo ) and that thing runs day in day out @ 110-130 degrees and at the track I've seen it 150+ and thats with a massive oil cooler and 8L of oil, what is the deal with those things??

When you're designing an engine for efficiency, thin oils are better. AFAIK that's a common grade these days. Not sure about how long the oil will last at 150 tho. Would be good to get it analysed to check its condition.

[luvpsi]

I can't believe HSV's run 5w30, ( my bro's got a series2 malloo ) and that thing runs day in day out @ 110-130 degrees and at the track I've seen it 150+ and thats with a massive oil cooler and 8L of oil, what is the deal with those things??

which dealership do you work at, your probably seen it, or worked it, spent more time in the shop than on the road

anyway, on the oil, I used 5w40 mobil1 in for a while, did a one day motorkana, at the end of the day had no oil left in the motor ( well just enough to run, didn't register on the dip stick ) just too thin....

now use Nulon 15w50 no such problems I'm sure I don't have the same clearances as a factory motor, but that was my experience.

i work at city motors.

so in other words everyone you would give the 5w30 a miss. it was only a option as i can get it cheap

[tricstar]

i work at city motors.

so in other words everyone you would give the 5w30 a miss. it was only a option as i can get it cheap

think my bro's ute went to Melville and Shacks, then with 15k km's on the clock smashed valves into pistons and then broke a cam shaft no warranty because he had OTR induction and tune

anyway back to oil, I'm no oil expert, but for me even the 5w40 was too thin for my engine

[tricstar]

When you're designing an engine for efficiency, thin oils are better. AFAIK that's a common grade these days. Not sure about how long the oil will last at 150 tho. Would be good to get it analysed to check its condition.

yeah I agree oil analysis would be a good idea, however bearing in mind how close the oil temp sender is to the exhaust manifold ( to close for my liking ) I suspect it might not be a true reading ? ( surely thats not the case on a new performance car )

It doesn't go to the track anymore, they are just not built to be driven hard,

[MrStabby]

anyway back to oil, I'm no oil expert, but for me even the 5w40 was too thin for my engine

What happened with the thin oil? 5w40 works well for me.

[luvpsi]

ok well its a going to be a short interval due to it needs a 100 000kms service in 4000kms time. i also have a bottle of 10w40 magnatec in the garage that i bought for my girlfriends car and never used it would this be ok to run in it for a short amount of time

[tricstar]

What happened with the thin oil? 5w40 works well for me.

good question ? catch was clean, never get any blowby in there, I'm assuming it just blow out the back, there did seem to be an abnormal amount of black shit on the bumper.

anyway spoke the guy that built it ( Nisspeed in Adelaide, James ) and said it was too thin for my engine and he always used Nulon 15w50 especially if its going to get drive hard and see highish temps.. no such problem since I changed back to Nulon, doesn't hardly use any at all now..

I really looked into it when I changed to Mobil1 and I thought it was "the shit", but it comes down to what the engine is built to run.

[luvpsi]

and if its stock?

[tricstar]

and if its stock?

ok don't know about the Magnatec, but in a stock motor, mobil1 5w40 would probably be fine, I'm sure a lot of people including Mr Stabby use it with no issues, it's just different oils for different applications

[luvpsi]

i wouldnt use the magnatec all the time its just for a short interval til i do my 100 000km service

[MrStabby]

ok don't know about the Magnatec, but in a stock motor, mobil1 5w40 would probably be fine, I'm sure a lot of people including Mr Stabby use it with no issues, it's just different oils for different applications

FWIW I was actually using Delvac1 5W-40 as its a bit tougher under stress than Mobil 1 0W-40. Can you get Mobil 1 in 5W-40? I'll probably go for Mobil 1 0W-40 next time as its easier to get.

Remember factory fill is a 7.5W-30!

I would always go with what the engine builder recommends, even though I think many of them are stuck in the past WRT oil viscosity.

If the mangatech is a full synth, it will be fine.

[luvpsi]

so in other words the 5w30 should be fine

[tricstar]

FWIW I was actually using Delvac1 5W-40 as its a bit tougher under stress than Mobil 1 0W-40. Can you get Mobil 1 in 5W-40? I'll probably go for Mobil 1 0W-40 next time as its easier to get.

Remember factory fill is a 7.5W-30!

I would always go with what the engine builder recommends, even though I think many of them are stuck in the past WRT oil viscosity.

If the mangatech is a full synth, it will be fine.

yeah maybe it was 0w-40

[mystery_kid]

i've not seen mobil 1 5w40 around...

i've seen 0w40 / 5w30 / 5w50 or something

i just changed mine to mobil 1 gold 0w40 in my rb25 neofrom whatever castrol shit was in there before, that only ever got changed every 6 months by the previous owner

Edited July 27, 2011 by mystery_kid