The Goods On Oils

[PHaT MR30]

This information kindly provided by Rolls, some_cs_student, & trex101

When choosing oils the better the rating, generally the better the oil, and also the more expensive. Keep in mind even the Group II oils are probably still better then any oil that was made when your car was manufactured.

Basic explanation of ratings

Group I - mineral

Group II/II+ - hydrocrak (VI below 120)

Group III - hydrocrack (VI above 120, mineral derive "Fake Synthetic")

Group IV - polyalphaolefin (man made Synthetic)

Group V - Ester & other un-group fluid (Ester or Polyolester, super high grade Synthetic, good for aircraft jet engine).

Common products and their ratings.

Redline (Group V Polyester)

Motul 300V (Group V)

Motul 8100 E-Tech 0W40 (Group IV/V Blend)

Mobil 1 (Group IV)

Motul 8100 xcess 5w40 (Group IV) ~$59 - one of the best value

Castrol SynTec 0w30 (Group IV) [A minor mistake in the front page, Castrol SynTec 0w30, the German castrol is group IV. The American 5w40 or similar is group III (sometimes written as III/IV but not true group IV).]

Castrol Edge Sport 5w30 or 10w60 (Group III)

Motul 4100 Turbolight (Group II?)

Keep in mind that the 100% synthetic stickers mean jack, just means that the oil is at least Group III. As far as viscosity ratings go, this depends entirely on what temperature range your car is going to be used in and your driving style (track or street car) A decent read through this thread should help you answer that.

As far as oil filters go, get a genuine nissan one if you don't want to spend much, these are superior to ryco/cooper.

On Selecting Which Viscosity

There is alot of factors to consider when choosing oil weight and it's quite difficult to give you any good advice by your above description.

There are 2 major considerations in choosing oil viscosity,

1) Fuel dilution (fuel blowby into oil sump effectively thin down the oil viscosity)

Thicker oil can withstand more fuel dilution then thinner oil but thicker oil also causes friction drag, slower spool, higher FC and more startup wear.

For example: If you run Penrite Sin 25 25w60 in your engine, at 10’c morning when you first crank your engine, you would have effectively run 1131cSt startup viscosity. That’s like 4.5 time thicker then Mobil 1 0w40 (248.8cSt@10’c). It’s like running greases through your engine instead of oil.

2) Engine oil temp

Higher oil temp effectively thins the oil down.

For example: Mobil 1 0w40 is 14.3cSt @ 100'c but when avg oil temp raise to 120'c, it would have thin down to 9.1cSt which mean that it is effectively a 20wt oil (you do not want to run a 20wt oil when you racing down a track, do you). So if your avg oil temp are 90’c, any 30wt oil will do as it is effectively a 40wt oil at that temperature.

The key to the correct oil viscosity depends on mostly the above 2 conditions. There is no one size fit all oil.

Oh, IMO some brand of oil are known to withstand quite abit of fuel dilution before thinning down. Redline & German Castrol is one of them. That’s why it’s highly recommended in BITOG for track or high hp muscle car usage.

[JimX]

I'm using Castrol Formula R 5W-30 (full synth). It costs $50 for 5 litres from Auto 1.

Edit: I no longer use the above oil. Not so much for the thickness of the oil but mostly because I think it's hell dodgy for a synthetic oil. I gave up using Castrol long ago.

[KamikazeR33]

one tip: dont let ppl at places such as autobarn, auto 1 etc tell u what u should be using... silly me got conned into using some pennzoil 20w60

car doesnt idle when cold! too thick

[rb25]

Motul Turbolight 4100. I was using Mobil1 before and wasnt happy with it at all. Now im sticking with the Motul...

[terry.m]

Even though I don't have my R33 yet, I have been doing heaps of research on what oils to use. Ask companies like Autobarn, Supercheap, a simple question and you get a stupid answer.

From what I can gather, Nissan recommends 7.5w-30 for the engine.

Shell recommend the following for the R32 GTR, I can assume that most RB engines would be the same:

Engine: Shell Helix Ultra (Synthetic) 15w-50 or 5w-40

Man Tranz: Shell Spirax CX 80w-90

Diff: Shell Spirax AX 80w-90

Power Steering: Shell ATF Dexron III

There is a huge price difference. In Adelaide, Castrol Synthetic and Fuchs Titan oils are a rare find. Repco want $80+ for Castrol 0w-50 (Yer right). Mobil 1 seems to be around the $65 mark. I found Shell Helix Ultra at Big W for $43 for 5L. I currently use Helix Ultra in my N14 Pulsar and will prolly use all Shell products in my R33. Shell seems to be the better 'Bang for your Buck'. Castrol and Repco can shove their $80+ bucks...it can't be that much better.

[JimX]

I slightly over-filled my oil on its last service. I was thinking that since it's so thin, it would probably get burnt off back down to the top line. But after 2000km it hasn't even moved a millimetre downwards on the dipstick. If your engine is still tight (as mine is) then the thinner you can go the better.

The cold weight should always be around 0-15 or so, because your turbo needs a thin cold viscosity to quickly lubricate the bearing after startup. The engine also likes a thin cold oil to get to the upper engine parts quicker.

The hot weight is less important, it can range from 30-60 easily with no adverse consequences aside from less power/economy at higher thicknesses, or worse protection and higher oil usage at thinner viscosities if your engine is worn.

But if your engine isn't using any oil at all, go a 30 or 40 weight for the hot viscosity. My Commodore was running 15W-50, and it was still using about 2 litres of oil every 10000km. I think the only oil that gets used in my Skyline is out of the sump plug and filter during servicing

[Roy]

I have always been happy using Mobil 1, but its getting up to almost $13 a litre so would be interested if there is a good oil at say around $10 litre.

Mobil 1 is just getting too expensive, im doing about 5,000kms every 4-5 weeks, and usually change the oil well before 5,000kms, so looking for a better althernative.

Also interested in something like a 15W-50 oil as my engine is getting pretty high in kms

[Sumo]

I am running a Caltex Havoline 5w-40, and it still hasn't quitend down my lifters.... So im going to try mobil 1, might get a better response out of it...

Terry.m: I recommend Shell Fully Synthetic Diff oil.... awesome shit and it will quiten the diff down (did for me). It costs $24.95 a litre, but you only change the oil in the diff every 50,000kms or so.... So I think its well worth it.

[Sumo]

P.S. The diff takes a bit under 2 litres.

[PHaT MR30]

hmm,

well i have been using hpr 30. before that i dunno what my car had in it.

i know that mobil 1 is what all the SR boys are using, but have heard good results from Motul and Fuchs.

maybe i should use a different multigrade cos my car has trouble cranking and idling when cold, and its still supposedly tight, i don't need a thin oil like 5w i don't think as its not turbo

what do ppl think?

[WazR32GTSt]

penrite hpr 15

its semi-synthetic 15w60

car loves it and i change not one k over 5000

as long as its not completely shit anything that's either full or partial synthetic will do if you change every 5000kms...

[hippy]

i overfilled mine by like 1cm LOL havne't lost a drop after over 7000kms LOL

[red17]

I use Mobil 1 10W/30 Tri-Synthetic. Good stuff, but expect to pay a fortune for it. I get mates rates and its still 15 bucks a litre.

Pennzoil 10W/30 isnt too bad, used to run it all the time in my SR20 Pulsar, that thing still didnt burn a drop of it when i sold it with 240,000 on the clock.

Red17

[Guest RedLineGTR]

OKay tell me this why is Tri-Synthetic more expensive than some full Synthetic oils

[terry.m]

Because it's "Try" Synthetic, the marketing was much more expensive

[unwritten law]

i am using motul 4100 turbo light. its 10w 40, seems to be pretty good. I might go for the motul 300V which is supposed to be better.

[Bleach1]

I use Mobile 1 0w40. Costs me all of $0 a Litre and i have about 20 Litres stockpiled in my car port, it helps working in a workshop. I have never had a prob with it. The person i baught my car from was using penzoil (rubbish) and with the Mobil i noticed the engine free up.

I work at an auto 1 on the weekend for extra cash and alot of guys who work at repco/auto1 and so on dont have a clue about cars or spare parts other than Falcons or commodores.

KamikazeR33, whoever told you to use Penzoil 20W60 is part of the 'there are no other cars other than falcons and commodores' psyche that ussually work in auto1/repco/supercheap stores.

[dAVE]

i had mobil 1 in mine.. 5w 50 or whatever the usual shelf stuff is. Was okay, but not much better than cheaper oil. Was about $50. Just changed to motul 4100 turbo light and already feels better.. around $40.

[Guest RedLineGTR]

it just depend on what people recommend. Use whatever is in your budget.

[JimX]

The 2 main guidelines you should probably follow regardless of brand recommendation are:

1. Use a full or semi-synth.

2. Don't use too-thick oil, especially with the cold weight number. (hot weight isn't too important unless the engine is a bit worn in which case you should probably stick to 50 or 60 for the hot weight)