Everytime I do an oil change I get about 0.5L remaining and have accummulated about 3L. There is no expiry date on the bottle so was wondering if I accumulate enough I would get a 'free' oil change. How long does oil last in the bottle? It's Mobil1

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There's a hoon in every Typhoon

For ever & ever & ever

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Beaten up old 98 Gen 2 Liberty, 13.0, stock V3 STI running gear.
07 Transit motor home
69 VF & 70 VG Valiants needing full restoration
Yamaha Zooma 50cc rocket hopefully going with the Transit.

Yeah i've always asked this too, as i found a 5 litre bottle mobil synth s 5-40 in my shed from my silvia, and it looks like i've used it to top it up, thats it.

Might pass it onto a fellow owner or something.

I use the last .5l of every bottle to try and flush out the older stuff before throwing in the new oil.

Or use that leftover portion of oil 1st and start with the new bottle that way it stays fresh.

It has been discussed @ gtrydaz.

Don't be cheap. :P

as long as the bottle is sealed and doesn't get exposed to weather ( sun, dust, water etc etc ) it will last for a loooooong time.

as some one else said, i use the old/left over oil first when doing an oil change so you always have new leftover oil.