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Hi,

Just searched everywhere and cant find the answer to what im looking for! Just looking for a good engine oil to use. What im unsure of is exactly what kind of engine oil to use for my possibly genuine 75000km.

For example 5w-40 etc.... and also what is a good brand? its for an RB25DET.

Also what do you guys think of oil flushing fluid as in beneficial, before changing oil?

One more thing what are you guys using in ur similar km RB25DET?

Thanx

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Seconded on the Motul on all accounts, I use the 8100 5W-40 myself. However... If you are changing from another brand or if this is your first oil change, you *may* want to do an engine flush once, because Motul dissolves a lot of sludge on its own. When I swapped from a crappier brand to Motul after about a year, it dislodged a fair amount of sludge and blocked a lifter and the car wouldn't start due to loss of compression. I towed it to my mechanic (I didn't know what was wrong) and he then had to run an engine flush through it to fix it. He suspected that it might have been a failed lifter but once flushed properly it never had any problems. Running Motul from then on has kept it clean and running really well.

Dont do the engine flush!! and it may be extravagent using the high end motul oil.

I just use castrol magantec and change it every 4000-6000km. Used it for around 20k km now and doesnt use any oil. At almost 110k km now.

Works well. Plenty of other things to blow your money on besides oil that you should change regularly anyway.

Hi,

Just searched everywhere and cant find the answer to what im looking for! Just looking for a good engine oil to use. What im unsure of is exactly what kind of engine oil to use for my possibly genuine 75000km.

For example 5w-40 etc.... and also what is a good brand? its for an RB25DET.

Also what do you guys think of oil flushing fluid as in beneficial, before changing oil?

One more thing what are you guys using in ur similar km RB25DET?

Thanx

Yes use a ester oil like 300v or Redline, they both clean very very well.

  • 1 month later...
I just use castrol magantec and change it every 4000-6000km. Used it for around 20k km now and doesnt use any oil. At almost 110k km now.

Works well. Plenty of other things to blow your money on besides oil that you should change regularly anyway.

i heard the technology behind this oil is that it sticks to engine, hence the name magnatec.... so when other oils drain to the bottom of the engine as they cool/overnight etc the oil "sticks" to the engine..... its sounds good in theory but i also heard the yucky stuff like sludge also sticks as well with the oil... so when you change your oil some of it stays in the engine.......

i heard the technology behind this oil is that it sticks to engine, hence the name magnatec.... so when other oils drain to the bottom of the engine as they cool/overnight etc the oil "sticks" to the engine..... its sounds good in theory but i also heard the yucky stuff like sludge also sticks as well with the oil... so when you change your oil some of it stays in the engine.......

All modern motor oils have the "sticky" technology, if you can even call it technology. If they didn't, engines would wear out a hell of a lot faster whenever they were left overnight without running. If you want a form of proof, buy a new set of disc rotors. They will have a thin film of oil coating them to stop rust, and it doesn't matter if they are stored for years it will still have the same coating of oil.

Magnatec is just a marketing gimmick. If it really has some sort of extra magnetism (why?), that would imply some sort of ferrous component in it. Would you really want iron filings floating through your engine sticking to all the metal? All good oils have a decent amount of detergent in them too, to help avoid the buildup of "sludge" that they will all get if left to cook inside an engine long enough.

This post is not aimed at you, it's just addressing the Magnatec. I prefer to use a full synth rather than subscribe to mainstream marketing gimmicks. Magnatec seems to be an otherwise decent oil but there are much better choices. The main thing turbo cars need to contend with is the breakdown of the oil at high temperatures, and full synthetics generally have a higher temperature tolerance than semi synth or mineral oils.

All modern motor oils have the "sticky" technology, if you can even call it technology. If they didn't, engines would wear out a hell of a lot faster whenever they were left overnight without running. If you want a form of proof, buy a new set of disc rotors. They will have a thin film of oil coating them to stop rust, and it doesn't matter if they are stored for years it will still have the same coating of oil.

Magnatec is just a marketing gimmick. If it really has some sort of extra magnetism (why?), that would imply some sort of ferrous component in it. Would you really want iron filings floating through your engine sticking to all the metal? All good oils have a decent amount of detergent in them too, to help avoid the buildup of "sludge" that they will all get if left to cook inside an engine long enough.

This post is not aimed at you, it's just addressing the Magnatec. I prefer to use a full synth rather than subscribe to mainstream marketing gimmicks. Magnatec seems to be an otherwise decent oil but there are much better choices. The main thing turbo cars need to contend with is the breakdown of the oil at high temperatures, and full synthetics generally have a higher temperature tolerance than semi synth or mineral oils.

Most likely Magnatec are using group II base oil which contend some element of ester. Ester has been added to some engine oil for it polar effect which 'cling' onto any surface it pass thus lower the startup wear. Oh not all oil are added with ester as ester are 5 times more expensive than mineral base stock.

Now you know why Redline are hell of expensive when compare to normal synthetic...

Some oil i know that contain ester

Redline - mostly ester base

Motul 300V - mostly ester base

Fuchs silkorene - mostly ester

Delvac 1 - small percentage of ester

Magnatec - unknown percentage of ester (likely small amount)

Trex, you seem to know quiet a bit about oils. May i ask what you do for a living?

Also, what do you think of motul 8100 5w40? does it contain those good group iv/v oils? what about esters? good additives?

You also seem to like Delvac 1 - is this fully synthetic?

Thanks heaps mate.

Trex, you seem to know quiet a bit about oils. May i ask what you do for a living?

Also, what do you think of motul 8100 5w40? does it contain those good group iv/v oils? what about esters? good additives?

You also seem to like Delvac 1 - is this fully synthetic?

Thanks heaps mate.

I'm work as a aircraft mechanic as my day job and import/supply performance lub to local clubs as a sideline/hobbies.

Motul 8100 5w40 may not contain ester in it's oil formulation. You may want to choose 8100 0w40 if it's ester you are looking for .

Yes, Delvac 1 5w40 are fully synthetic using a blend of PAO/ester couple with a pretty strong additives pack and it's cheap too over in Aussie.

Another good read about polyolester.

polyolester - redline oil

Edited by Trex101

motul 8100 5 w 40 costs me $52.

delvac is about 30-15.

So is the delvac 1 act5ually better than the 8100(non ester)? So it's cheaper and better?

I'm a bit weary about using the delvac oil. U sure it's ok? I was reading the mobil site and it said it was for diesals.

Cheers mate.

So say if I had an oil budget of 50-60, what would be the best I could buy?

Is ester a lot better than non ester?

What do you think of elf excellium 5 w 40? Does it contain much ester? and is it made of good oil? I can buy it for $45.

Thanks heaps for your help. I don't understand the informaiton that the sites say about their oils.

So say if I had an oil budget of 50-60, what would be the best I could buy?

Is ester a lot better than non ester?

What do you think of elf excellium 5 w 40? Does it contain much ester? and is it made of good oil? I can buy it for $45.

Thanks heaps for your help. I don't understand the informaiton that the sites say about their oils.

Yes, ester is better in alot more ways than normal PAO synthetic but it comes at a price. Delvac 1 is dual rated API SL and CI-4+,

API SL = suitable for petrol engine

CI-4+ = suitable for high output diesel engine

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