Time to switch oils?

[DOB81]

Everyone's LS motors seem to like a different oil. Mines done 175kms and ticks if I use thicker oils. It's fine running full synth 5w30. Thicker oil is not always the answer. On another note, no oil will cause gumming or sludging if you always use the same oil and change it regulatory. Using different brands is was causes build up in engines (and prolonged intervals of course) Doing a flush before changing brands helps this issue. So any decent brand is good as long as you change it regularly and stick with same oil once your happy with it. This was the advice given by an engineer friend that had done a course in lubricants.

[Micks]

Our LS engines run close tolerances so yes thicker oils are not recommended, don't think 5w/30 is great for a LS1 but each to their own!

[Jason01]

Our LS engines run close tolerances so yes thicker oils are not recommended

So how come nearly everyone here is always saying run Edge 10W60 then?

[DOB81]

Each to there own I suppose. The oil cap says 10w30 so I can't see how 5w30 would be an issue. The fist number is just the winter weight and is only relevant at start up. The lighter the better. 5w30 is what everyone in the USA uses including the hot states. I can understand people using heavier weights than the recommended 30, if you are using your car for majority race use, but if you are like me and 95% of driving is normal and 5% is having fun then you are wasting your money on expensive heavy weight race oils! In fact you could argue it's doing more harm than good. Heavier weight race oils are designed for extreme race conditions and high temps. If you do not expose your car to these conditions most of the time the oil is not working efficiently. LS motors are all alloy meaning they disperse heat very well. When I experimented with heavier weight oils it took nearly twice as long for the car to get to full operating temp. Considering that warm up is the time most wear occurs this is probably not ideal! The heavier weight oil also struggled to maintain pressure through the lifters on warm up causing ticking. Ticking equals damage to the cam lobes. LS1 motors were also designed to be quite low on oil pressure at lower RPM. Therefore many people think that a heavier oil is needed to increase pressure which is wrong. More flow is needed. Hence why GM recommends a 30 weight for LS1. Many new vehicles including high end makes are asking for 20 weight oil. The new mustang is an example.

[Micks]

So how come nearly everyone here is always saying run Edge 10W60 then?

I personally don't like Castrol but It depends how your using your vehicle, in my case with the VZ L98 has 100K, cam, springs, L76 higher flowing pump, extremely good oil pressure both cold & hot 80psi @ full noise. Tried many weight oils in this & found 10-60 Penritre full synth best for me & the the top end is noticeably quieter too. So much so I run it in all my 3 V8's now.

[Jason01]

I personally don't like Castrol but It depends how your using your vehicle, in my case with the VZ L98 has 100K, cam, springs, L76 higher flowing pump, extremely good oil pressure both cold & hot 80psi @ full noise. Tried many weight oils in this & found 10-60 Penritre full synth best for me & the the top end is noticeably quieter too. So much so I run it in all my 3 V8's now.

Castrol, Penrite, 10W60 is still 10W60 which is the higher end of the kinematic scale. Top fuel motors usually run 25W70.

My LS1 goes over 80psi above 5000RPM and 58 - 60psi at 2000RPM highway cruise hot (20 - 25psi too much in my opinion) with a Melling 10295 and LS30 (5W30). Too much oil pressure just uses up power, there's no use having shitloads of oil pressure if the oil is not flowing enough to do it's job properly, a big part of which is cooling.

[Jason01]

Each to there own I suppose. The oil cap says 10w30 so I can't see how 5w30 would be an issue. The fist number is just the winter weight and is only relevant at start up. The lighter the better. 5w30 is what everyone in the USA uses including the hot states. I can understand people using heavier weights than the recommended 30, if you are using your car for majority race use, but if you are like me and 95% of driving is normal and 5% is having fun then you are wasting your money on expensive heavy weight race oils! In fact you could argue it's doing more harm than good. Heavier weight race oils are designed for extreme race conditions and high temps. If you do not expose your car to these conditions most of the time the oil is not working efficiently. LS motors are all alloy meaning they disperse heat very well. When I experimented with heavier weight oils it took nearly twice as long for the car to get to full operating temp. Considering that warm up is the time most wear occurs this is probably not ideal! The heavier weight oil also struggled to maintain pressure through the lifters on warm up causing ticking. Ticking equals damage to the cam lobes. LS1 motors were also designed to be quite low on oil pressure at lower RPM. Therefore many people think that a heavier oil is needed to increase pressure which is wrong. More flow is needed. Hence why GM recommends a 30 weight for LS1. Many new vehicles including high end makes are asking for 20 weight oil. The new mustang is an example.

Come on mate this is Australia, thicker is always better .

[Jason01]

Castrol, Penrite, 10W60 is still 10W60 which is the higher end of the kinematic scale

Apologies, meaning for oil viscosities and having some variation within the grade of course.

https://www.bobistheoilguy.com/wp-co...11/03/visc.jpg

[DOB81]

Definitely not arguing that thicker oils have more capacity for protection against wear. My argument is that unless you subject your car to extreme conditions more so than not, then the extra protection would be negligible if any. Also just because a heavier grade of oil has the capability for a higher level of protection, does not mean it is suitable for all applications. If an engine is designed and recommended to use a certain grade oil then there is reasons behind that. Sure a bit higher like a 10/40 won't hurt, but wasting money on expensive 50+ weight race oils for a daily driver is probably over kill and will make an immeasurable difference for the time you are likely to own the car. And in some cases may actually cause issues as it did for me. But that's just my opinion. If people feel better about spending unnecessary money on heavy weight race oils on daily drivers then go ahead.