Re-using 1 year old oil in second car

[Matt_T]

I have a 1993 NSX that does about 1200 miles per year, I get an annual oil change using premium branded 5W-30 synthetic oil.

Now, the oil that comes out still looks pretty golden and clean - my question is am I fine to then put that oil in my old civic and run it for another year?

It feels like a complete waste to throw it away and go and buy another 5 litres.

Thoughts?

[SturdyHSV]

Assuming it's a similar grade to what the old Civic is expecting, yeah personally I would.

Realistically even if replaced with new oil, in 1,200 miles your Civic would have 1,200 mile old oil in it, and I don't imagine that's going to kill it any time soon!

If you wanted to be really fancy, you could send off a sample for oil analysis, and make your decision based on the results...

[ARHarh]

Are you doing these oil changes yourself? If not you are really going to struggle to find someone who will, give you back your old oil, and or use second hand oil in an oil change.

Whole thing seems a daft Idea when you can buy a gallon of new oil for £25.

[Dynion Araf Uchaf]

ARHarh said:

Are you doing these oil changes yourself? If not you are really going to struggle to find someone who will, give you back your old oil, and or use second hand oil in an oil change.

Whole thing seems a daft Idea when you can buy a gallon of new oil for £25.

you just suck the oil out of the nsx with a pump and then tip it into the civic. lot cheaper than £25.

[E63eeeeee...]

Probably fine, but also potentially a way to change one dying engine into two dying engines. Are you at least going to put it through a filter or something first?

[tux850]

Whilst you've said the NSX only covers 1200 miles/year but what sort of journeys are those? Many short trips or fewer long ones? If the former then the oil might be degrading from from picking up water (that doesn't get evaporated off) and that might not manifest itself in an observable colour change.

Personally I wouldn't reuse it. The cost saving doesn't seem worth it given the uncertainty over potential consequences.

[Pica-Pica]

E63eeeeee... said:

Probably fine, but also potentially a way to change one dying engine into two dying engines. Are you at least going to put it through a filter or something first?

I think most cars have filters nowadays.

[BoRED S2upid]

Yes be fine. Back in the day we ran an old BMW as a work hack it did 20,000 miles a year between 3 of us and we changed the oil every 2 years no expense was spent the oil was like treacle.

[Matt_T]

ARHarh said:

Are you doing these oil changes yourself? If not you are really going to struggle to find someone who will, give you back your old oil, and or use second hand oil in an oil change.

Yes, NSX is serviced by specialist who gives me the oil, the Civic I service myself on the drive.

[Matt_T]

Pica-Pica said:

E63eeeeee... said:

Probably fine, but also potentially a way to change one dying engine into two dying engines. Are you at least going to put it through a filter or something first?

I think most cars have filters nowadays.

No, but the Civic will have a new oil filter when it recieves the oil. I very much doubt there will be much in the oil after 1200 miles...

[finlo]

wyson said:

I’d get the oil lab analysed first. If it comes back with a clean bill of health, why not reuse it?

I’d want to make sure that nothing is amiss in the NSX and retest it periodically.

Edited by wyson on Wednesday 17th July 17:57

Does the lab test not cost more than a gallon of oil?

[ChocolateFrog]

Personally I wouldn't bother but it'll be absolutely fine and does make sense from an environmental point of view atleast.

[John D.]

Why not just leave it in the NSX until next year?

[grumpynuts]

Sounds like a great idea.I used to own an old mk1 ford escort which used and dripped oil in huge quantities, so i used to top up the oil with used oil and had no engine issues other than the fact it was knackered anyway.
1200 mile oil is fine to put into an older car and seems really good common sense.

[donkmeister]

Seems like a fine idea, but you'd need to be fastidious about cleaning around the sump plug in the NSX before removing it, and ensuring your drain pan is properly clean first.

You don't want to be pouring a gallon of oil and some grit into the Civic.

[Matt_T]

Thanks everyone, some good advice there.

[hidetheelephants]

wyson said:

finlo said:

Does the lab test not cost more than a gallon of oil?

Yes they do. So test now, get all clear. You know the NSX engine is good as a side benefit. Oil test again in 5 years etc. Not suggesting he test the oil every year before every transfer.

Or just don't test it because it's a waste of time?

[Belle427]

I do get it but its not something I could do for the sake of £20.

[joshcowin]

Why not get more value from the oil and use the NSX more! That's a win win, the oil change will be required and you will have used your lovely car not only pleasing yourself but also any car fans you encounter! An NSX is a rare spot now!

[GordonGekko]

How much is your time worth in faffing about to save relative pennies?

Buying Mannol 5w30 on a discount day it is even lower price than this….
https://www.ebay.co.uk/itm/186510850931?gad_source...