the best oil???

fett said:

oops I ve got 10w40 semi in there at the moment on 1990 3.9,

Should I drain and replace?

I was going to put castrol magnatec 10w40 semi in next as I do lots of short trips, should I not?

Thanks

John

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use normal mineral oil in your engine not synth or semi-synth.

Is it ever worth putting slick fifty in these as well as the oil?

I got a bottle for my birthday about 15 years ago and never used it .

fett said:

Is it ever worth putting slick fifty in these as well as the oil?

I got a bottle for my birthday about 15 years ago and never used it .

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personally i would,nt use it,1st i dont like the stuff,2nd it might have deteriorated after 15 years.

I never use additives. If they are good for your engine, oil producers and petrol refiners would put the stuff in already.

hammy2909 said:

I never use additives. If they are good for your engine, oil producers and petrol refiners would put the stuff in already.

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really, i reckon they won't!

But it's not them that makes the additives, is it?

Reading all the posts I can understand not using additives and not using fully sythetic as its very thin , But how is a good 10w40 semi synthetic going to do any harm?

I really would like the technical facts.

Thanks

John

landowner said:

I've got two gallons of Castrol 'R' ithe garage but someone told me not to use it in the V8 as it would ruin the engine

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castor oil is a one use only type race oil and tends to be a monograde so dont use it

fett said:

Reading all the posts I can understand not using additives and not using fully sythetic as its very thin , But how is a good 10w40 semi synthetic going to do any harm?

I really would like the technical facts.

Thanks

John

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its a bit of a myth all this mineral is thicker than synthetics stuff

a 10w is a 10w whether its mineral or synthetic

what engine do you have?

fett said:

oops I ve got 10w40 semi in there at the moment on 1990 3.9,

Should I drain and replace?

I was going to put castrol magnatec 10w40 semi in next as I do lots of short trips, should I not?

Thanks

John

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magnatec is not a good oil bud, chances are you've already put better oil in it than that

the standard recommendation for your engine is 15w-40 and the premium is 10w-40

zddp (zinc) additive (that should already be in the oil) is pretty important in older engines, the more modern the oil the less ZDDP there will be in it as it attacks exhaust treatment devices

the 10w will not thicken as much when it gets cold so will get around the engine faster when you start up which is a good thing.

wrxfifer said:

so castrol multigrade 20/50 it is any idea how much i will need after its fully drained?

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20w-50 is gonna be a bit thick i think bud unless your in a hot country

desertrover said:

Interesting thread this.....I recently had an oil change, and topped up my 2.5DSE with fully synth Comma 10/40...have I made a mistake?...local Bearmach shop said that I should use it....I thought it might be a bit "thin" for my old duchess...she's got 110,000 under her girdle bless her!....I thought she would have benefited from something a bit more viscous in her belly!??....What about oil additives...Wynns Oil Treatment etc...are they recommended?...Lets hear it from you exspurts.

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i dont think comma make a fully synthetic 10w-40 it will probably be a semi synthetic

10w-40 semi synthetic is the perfect oil for your engine

ps. dont use any oil additives, blending oil is a complicated business and often if you upset the balance of the additives already in the oil it can have a negative effect

i have just done a some digging and according to comma you should be using XTECH 5w/30 in a 4.0L rangerover 1994-1998 it should hold 4.9L of oil so a 5L can should do ya the part no is XC5L most places will have to special order it

i just not long done mine and with the new filter it took 6l in total and i used gastrol gtx 10w 40 part mineral part synthetic seems to be fine! lol

I checked on Castrols website - GTX is mineral, Magnatec is semi synthetic and Edge is fully synthetic. I have to confess to having Magnatec 10-40 in my 4.6 at the moment but from all the comments will probably go back to GTX or similar next time.

surely my thread has done well over a 1000 views woohoo

So it really comes down to zinc?

In that case the old castrol 10w40 multigrade should be good if it hasnt had its ingredients changed for years?

Its a shame they dont do a magnatec with that zinc in it.

I have noticed that since around the time I put the no comma 10w40 semi in the 3.9 it is a bit more "cammy" on tick over

fett said:

So it really comes down to zinc?

In that case the old castrol 10w40 multigrade should be good if it hasnt had its ingredients changed for years?

Its a shame they dont do a magnatec with that zinc in it.

I have noticed that since around the time I put the no comma 10w40 semi in the 3.9 it is a bit more "cammy" on tick over

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it will have zinc in it

i mean fully synthetic low SAPS oils that modern cars require will have a lot less that the older spec oils

magnatec will be fine as it doesn't have much synthetic oil in it anyway

Mobil or Shell do better oils for your money if you feel the need to stick t the big brands

Car Oil & Filter service packs

you should be able to make the right choice here mate

enjoy

G-man said:

i have just done a some digging and according to comma you should be using XTECH 5w/30 in a 4.0L rangerover 1994-1998 it should hold 4.9L of oil so a 5L can should do ya the part no is XC5L most places will have to special order it

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It lists a product called Eurolite which is a 10w-40 semi synthetic bud


Welcome to the Comma Oil & Chemicals Ltd. Website

click on application guide

That looks like a good website for oil kits , thanks. Do you think thats the cheapest you have found?

I am glad they rcommended the oil I wanted originally lol.