What have you done to your car lately?

[chris_r]

Ordered the timing belt kit,

Didnt feel comfortable forking out $300+ for a GM kit from a supplier with a rating less than 99%

Went for gates branded items as ive used Gates parts before on previous cars and there stuff in my opinion is better than factory for most items.

unsure of the weight of oil ill be using though, previously i used a fully synthetic penrite 15w-60 (the extra +10 that they go on about)

To stick with penrite or swap to castrol edge?? decisions.

approaching 140k on the clock.

I've used Penrite for the last few years in all my cars, it's never let me down.

If you change brands or even grades of oil, remember to run a can of engine flush through it before draining the oil.

[vekara]

I've used Penrite for the last few years in all my cars, it's never let me down.

If you change brands or even grades of oil, remember to run a can of engine flush through it before draining the oil.

I am not an expert but flushing between brand changes are not necessary, i have been told, all oils are more or less same, the additives vary. BUT... flushing the system gets all the dirty old oil out.

[SilentShout]

Both Penrite and Edge are great oils, i have used both and now using Nulon which is great too.

Whats the nulon like? I remember it was sort of new to super cheap before I stopped working for them. They claim to have all these low friction benifits which help economy and regain engine power blah blah blah. Didnt buy into it then but they are still around so it must be working.

As for grade is the 15w60 too high still? Didnt notice any adverse effects on the engine with it in there.

Also I use an engine flush between every oil change. Thought thats what the process is.

[chris_r]

I am not an expert but flushing between brand changes are not necessary, i have been told, all oils are more or less same, the additives vary. BUT... flushing the system gets all the dirty old oil out.

Different additives are used to achieve different viscosity grades and the methods would probably differ between brands. Most of these additives maybe harmless when mixed together, but some aren't and will result in the formation of sludge.

For the few dollars it cost, especially when it comes to turbo engines, it is worth it to keep everything working well, regardless of whether you're changing oils.

[vekara]

I am happy with Nulon, "some say"... that it is same as top oils but cheaper and it is Australian owned. I put it in the same category as Castrol Edge. I also use Nulon brake fluid and coolant.

[vekara]

Different additives are used to achieve different viscosity grades and the methods would probably differ between brands. Most of these additives maybe harmless when mixed together, but some aren't and will result in the formation of sludge.

For the few dollars it cost, especially when it comes to turbo engines, it is worth it to keep everything working well, regardless of whether you're changing oils.

Oils also contain anti corrosion, cleaning additives, preservatives and so on but, when you drain the engine and change the filter the system becomes pretty much empty anyway. One thing thou is that when you drain the oil, the engine must be hot so that the thermostat for the oil cooler is open and drain the heat exchanger too.
I guess it does not harm to flush the system. Does the flush have any chemicals that interact with oil additives? And if you use the same brand oil all the time then you would not have different additives reacting with each other...

[Shadow110]

+1 for nulon, seems good and for the price and what my car is for I dont have an issue

Sent from my GT-I9505 using Tapatalk

[SilentShout]

might look at the nulon brands from now on then

I do love penrite and used it in the s15 religiously,

But the 15w 60 weight seemed very think for the SRI, i may be mistaken though.

[vekara]

might look at the nulon brands from now on then

I do love penrite and used it in the s15 religiously,

But the 15w 60 weight seemed very think for the SRI, i may be mistaken though.

There is another great Australia oil maker Hi-Tec, but it is harder to find from shops, they mainly supply the trade, Peps sell it though. I once met a lady from the engineering dept, she was an encyclopedia of oils. she explained me the pros and cons of using different oils for different engines and purposes and expressed the importance of using oils that are recommended by the manufacturer in each climate area. The engine designers decide what oil is best for the engine, so they know best. It is all about flow rates and penetration. too thin oil may not keep oil pressure high enough because it flows and leak too easily and fast through the small spaces in the engine and may not reach the farthest corner from the pump. Too high viscosity oil resist too much and may not penetrate tiny gaps where it should, for instance piston rings, there are oil rings first down the bottom of the piston and compression rings at the top. they all need lubrication. if the oil is too thick it may not reach compression rings because it cannot pass through oil rings, resulting in wear.
Also thicker oil resists more when hitting pistons and crank shaft resulting in loss of power at high revs.
However, if the engine is worn out then thicker oil may be used. In Z20LER engine recommended oils are 10-30w and 15-40.

[SilentShout]

I wonder what the miraculous innovative engineering excuse is behind the 60k service interval on the timing belt and water pump for the z18xe -_-