OK to fill with different oils?

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Fri 24 Sep 2004 16:17
OK to fill with different oils? - MarkSmith
Hi folks,

Got to change the oil on a '93 Nissan Sunny 1.4 tomorrow, but the car isn't really relevant.

I have four or five part-used bottles of oil. All 10W/40, all semi-synth, all good API SL stuff, all suitable for the car, but three different brands. (Halfords, Castrol GTX Magnatec, Vauxhall.)

Is there any problem in filling the car with two or three types of oil? I top up with different oils if I don't have any of the original left, but filling half-and-half?

Thanks,
Mark
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Fri 24 Sep 2004 17:21
OK to fill with different oils? - frostbite
I wouldn't see any problem with mixing the oils you describe.....but I daresay someone will.
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Fri 24 Sep 2004 19:16
OK to fill with different oils? - Roger Jones
There's a view from Castrol with regard to mineral oils here:

tinyurl.com/53mjr

I'd try an experiment, if the oils are by any chance distinctly different in colour: take a small quantity of each, shake and stir them up thoroughly together (ask a favour to use the mixer machine at a local domestic-paint shop) and let the mixture settle over several days. If they don't separate visibly, take a chance.
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Fri 24 Sep 2004 19:18
OK to fill with different oils? - Roger Jones
Ah, P.S.: as you will see from another post in the link thread, Magnatec is not a true sem-synth but an enhanced mineral oil.
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Fri 24 Sep 2004 19:51
OK to fill with different oils? - MarkSmith
Hehe, thanks for the reply Roger, but I have to do the job tomorrow (so can't wait three days for this test) and don't really want to go to all that effort for £12 worth of oil :-)

Unless I get a strong opinion to the contrary before tomorrow I'll go for it I think... and hope the claims that they can be mixed are true.

Looks like it'll be 90% "Halfords own" and 10% Shell Super Helix or Vaux.

Thanks!
-Mark
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Fri 24 Sep 2004 20:42
OK to fill with different oils? - Civic8
Mineral oil should be ok with semi synth. I gather probs arise changing from mineral to fully.Or rather arent recommended.
I have mixed Mineral with semi never had a prob.
--
Was mech1
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Sat 25 Sep 2004 17:02
OK to fill with different oils? - quizman
Why don't you mix them up in your food blender, I am sure your wife/mother/sister won't mind.

I have never understood what semi-synth oil is,I wonder if it is like being semi-pregnant.
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Fri 24 Sep 2004 23:35
OK to fill with different oils? - Dalglish
I have four or five part-used bottles of oil. All 10W/40, all
semi-synth, all good API SL stuff, all suitable for the car,
but three different brands. (Halfords, Castrol GTX Magnatec,
Vauxhall.)
Is there any problem in filling the car with two or three
types of oil? I ...


the short answer is " no problem " - if you believe
www.chris-longhurst.com/carbibles/engineoil_bible....l
(link used to be in hj's faq ).

" Synthetics
Despite their name, most synthetic derived motor oils (ie Mobil 1, Castrol Formula RS etc ) are actually derived from mineral oils - they are mostly Polyalphaolifins and these come from the purest part of the mineral oil refraction process, the gas. PAO oils will mix with normal mineral oils which means Joe public can add synthetic to his mineral, or mineral to his synthetic without his car engine seizing up.
Pure synthetics
Pure synthetic oils (polyalkyleneglycol) are the types used almost exclusively within the industrial sector ..."

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Sat 25 Sep 2004 18:58
OK to fill with different oils? - Sprice
Shouldn't be a problem mixing oils, and anyway, the Sunny isn't exactly worth a lot if there is!
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Sun 26 Sep 2004 10:50
OK to fill with different oils? - MarkSmith
Sprice, whether the Sunny is or isn't worth much is really down to how much money the owner has. And the owner runs an 11 year old Nissan Sunny and gets a friend to do the servicing, so do you expect she has money to burn?

Thanks all for the comments. I feel pretty confident that mixing was not a problem.

Cheers,
Mark
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