Hi I’m going to give the car an oil change, would you recommend 10w30 fully synthetic or what do most on this forum use, also where do you buy the auto transmission filters thanks
I would not use fully synthetic as it gets too thin when hot form my use and trial, I suggest you ask the @oilman on club trader
Simon
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Most use a 10w 50 or 60
Although I’m of the opinion thinner is better so using a 0w 30 on a modified car.
You just need to change it frequently and at £80 a pop it can be expensive.
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So 5w/30 or 10w40 semi synthetic be a better choice then
Has 10w50 fully synth been on your tested list Simon? I found 5w50 fully synth comma motor sport oil reduced lifter tick, but then its thinner.
Hi
Fully synthetic is not thinner than a semi or mineral oil. If an oil is a 10w-40, it is a 10w-40 regardless of what it is made of. As there is more control of the blending when making a synthetic, you can make a synthetic thinner than a mineral based oil, but you can also make it thicker as well.
The most popular oil for GTOs is the Fuchs Pro S 10w-50 and that is a full synthetic oil, one of the very best on the market.
Cheers
Tim
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Hi
You should not go with a thinner oil in GTOs, I have heard.
/John
Are you absolutely sure!!! Quite the reverse!
I have run from stock to 1100hp on my GTO with 0w30 and 0w40 fully synthetic Redilne. Thicker = more resistance to flow. Flow = better cooling for your engine. Flow = less chance of lifter tick. The critical points are to select as thin an oil as possible that will maintain film strength / integrity without shear. It is also important to consider elements like VI (viscosity index) which is a measure of the rate of thinning with temperature.
At the bottom end I always try to select a 0w or 5w so that protection at start up from cold is as good as it can be.
A good guide for oil pressure is no lower than 10 psi per 1000 rpm, I tend to aim for between 10-15 psi per 1k rpm. I think our bypass comes in at 90 psi, so at 15 psi by 6k rpm your bypass is in operation!
André
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Very confusing all this really.
So you stiffly disagree with the well recommended Fuchs 10w50 then?
Lol Andre loves to throw a spanner in the works with oil!
His Gto is pushing 1200 bhp now so can assume he knows a bit about oil but assume again the oil is changed every few drag races. Unlike normal engines at ever few thousand miles
“Unlike normal engines at every few thousand miles” 
Terry 
How often you change yours terry??!!
Every 5,000 miles Steve, seems to be ok with that. Wouldn’t push it any further, though I did do 8000 when I first bought it, praying the cam belt would be ok 
Terry
Lol it would take me
8 years at current driving rate to hit 5000 miles 
Done 2.5 k since I’ve owned it!!
I think I’ve overused mine 
Probably done about 25k since I’ve had mine 
and its had loads of oil changes 
Terry
Well, I thought I knew what oil to use, now I’m lost!
Well @ViperGTO I use Fuchs Pro S 10w-50 after talking to as many people as I could, if they use and recommend it its ok for me 
Terry
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When I put new oil in mine I looked in the owners handbook on page 132 and it gives you all of the graded oils for different driving climates. My car has a few miles on it but is stored in a garage and not used in winter so i used a 20w-50 with seal swell as the handbook states and it runs better then it ever did with no noise increase at all.
That’s what I’ve used in the past. I’ve had the car 10 years so I’ve been through a few oil changes. It’s been sitting for over year now and maybe been 3 years plus since the last time I gave it a proper service. (I averaged less that 200 miles a year).
Lol Butler
It does get changed often but that is more to inspect for any signs of bearing break up. The other reason it gets changed frequently is because of the possibility of fuel dilution and blow by gases turning it acidic. Neither of these should apply to a ‘standard-ish’ car. By that I am talking about stock motor builds with stock cranks, ring gaps, stock pistons etc.
A huge point to note is that I used the same Redline 0w30 in my stock mk4 that had a DSBC as it’s only upgrade running around 350 hp. I put around 20k miles on that over 2 years and did oil changes every 4500 miles as per the book. It had some lifter tick when I bought it despite having the 3mm bore lifters as standard. The tick went away within a week of switching to 0w30 and never came back.
At the end of the day, folk will do what they feel is right for them, I can only post my own experiences and the reasons why I made those choices.
André
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