Thinking about servicing my own car - Need help with Engine Oil

[Nut Kracker]

This is a quote from the above link.....

I can't tell you how many times I have heard someone, usually an auto mechanic, say that they wouldn't use a 5W-30 motor oil because it is, "Too thin." Then they may use a 10W-30 or SAE 30 motor oil. At engine operating temperatures these oils are the same. The only time the 5W-30 oil is "thin" is at cold start up conditions where you need it to be "thin."

I was recommended by the person who did my engine, to use
10W-40, due to the Crane roller cam/lifters and Yella Terra roller rockers.

The reason......Need a thinner oil (10W) on cold start up to penetrate the roller bearings.

 

[lout]

religion, politics, and what oil to use
everyone has an opinion and "knows" best
we have 2 x VXII V6 commodores
after 3 year warranty holden servicing using 10W30 holden oil
then used mobil 1 10W30 gold up to 200,000km and genuine filters
then switched to 10W40 mobil 1 high mileage (off ebay) not available in Australia
one car now has 295,000km other has 260,000km
neither car has ever had an engine issue (besides both requiring LIM gaskets around 150,000km), no lifter noise at all
FYI the first number in an oil grade is the viscosity when cold, second number when hot

 

[graham7773]

I can understand some of the confusion here as Holden manual for VT series 2 3.8 V6 which I own says "for optimum fuel economy use 10w/30 SJ GF2 engine oil. If this is unavailable, use SG, SH, or SJ engine oil with viscosity of 20W/50 or 15W/40"...I have always used 20W/50. Seems to keep things a little quieter. How can one ignore the well educated engineers at GM?

 

[TI3VOM]

This is a quote from the above link.....


I was recommended by the person who did my engine, to use
10W-40, due to the Crane roller cam/lifters and Yella Terra roller rockers.

The reason......Need a thinner oil (10W) on cold start up to penetrate the roller bearings.

You do realise that 10W oil is only really needed in sub zero temps, it is already thin enough to get into every nook and cranny of you current engine setup.

 

[shadetreemechanic]

Firstly, great decision to service your own car. Its such a simple thing to do, practically everyone should be doing it...i see zero reason not to change your own oil.

You dont mention where you live so i assume its like most of OZ and its stinkin' hot in summer...valvoline engine armour 10w30 is an ILSAC GF-5 rated oil and that means its designed for fuel economy foremost.

For our hot summers id steer clear of eco oils. And look at buying full synthetic oil since its better.

 

[phillmac]

I buy up on the psudo full synth Nulon and Penrite when they are on special at Super cheap or Repco. Both good oils at good prices.
Grade depends on which car they go in. I pay a few $ more for factory filters after a Ryco failed many years back on a VY. Lucky those motor are bullet proof.
Heard other stories that lead me to believe the onus is on cost cuts in manufacture to save a few cents per filter. Also notice their adds referring to quality.
Always a give away.

 

[DevilDRake]

I use HPR15 (penrite oil), 15W-40/50 full Synthetic. If the engine was brand new I'd put thinner, but otherwise i go 15W.

 

[BlackoutSteve]

There is a huge misconception that old engines need thicker oil.
If an old engine consumes oil, then replace your valve stem seals as it's these seals that will be responsible for most/all oil consumption, unless your engine also has worn rings and produces blow-by.
..and V-configuration engines' rings last many, many hundreds of thousands of ks.
It's true that BandAid-ing with a thicker oil so it won't pass by your old brittle seals and valve guides will work, but a thicker oil is not required for your bearings and certainly not for the needle bearings in roller lifters.
Some years ago, GM release a bulletin and warned against using heavy oils in their LS engines (V6s use exact same lifter).
I can't find the actual bulletin, but JoeGibbs Driven LS30 Racing oil touches on it here in relation to break-in. GM LS Hydraulic Roller Cam Bulletin - Driven Racing Oil

The thermometer pic posted above is a misleading oil suggestion, but what I do like about it is that it's doesn't mention 50 weight.
Remember that the engine's thermostat will decide the running temperature, not the ambient. You may also note that from summer to winter, your gauge is pretty much always on 1/3 indicating adequate cooling capacity and little to no running temp variation throughout the year.
Choosing winter grades are important to get the oil around the engine as fast as possible and 0W, 5W or 10W is good. (Surprisingly many people don't know that the "W" in 5W30 means winter.)
GM standardized Delco Dexos is a 5W30. The oil in the owner's manual of my 69 Chevy is a 30 weight. The recommended oil for new Chevy crate motor is a 30 weight. The recommended oil in my WHs is a 30 weight.

These are the main and rod bearings of an SCV6.
That grey/silver nickel & tin layer that is on top of the copper layer, is only about 2 or 3 tenths of one thousandth of an inch thick (0.0002-0.0003") or 0.0050-0.0075mm. Typical bearing clearances are ~0.0025" or about ten times more in thickness than this top layer. This thin top layer is still there after 400,000Klms. So, how much additional clearance has the bearing clearance opened up in that time?
Now, tell me why this engine needed a 50 weight, or even a 40...

 

[EYY]

From the pic, those bearings look buggered. Thicker oils will fill the void from worn bearings and piston skirts, as well as reduce oil consumption due to poor oil ring control. Essentially just because the tolerances have become greater through wear. I agree that a thicker oil is just hiding the problems of excessive wear.

And to be fair, that's just one example of an engine that's done many km. Not all will be driven and maintained the same, and driven in the same environment. An engine that is serviced every 15,000km and spends half of it's life driving on dusty dirt roads will be much worse off than a car doing all highway driving in a clean environment which is serviced regularly

 

[vf sv6]

I have 4 commodores in the family, 1 vy-v6, 1 vx series 2-v6, 1 vx series 1-v6, 1 vt-v6, all use penrite hpr15 & holden filters never had any problems at all.