Mixing synthetic with regular engine oil?

[maxchao]

I'm gonna change my gf's Protege LX 1.6 engine oil this weekend. It seems it needs around 3.2-3.4 qt of oil. There were some 0.3 qt mobile 1 synthetic oil I left over from changing my P5's oil. She's refusing to spend money on the synthetic oil, so can I just buy 3 qt regular and pour that and my 0.3 qt synthetic oil into her engine?

Thanks

Josh

 

[i12drivemyMP5]

Shhhhhhhhhh, (whispers) the car will never know. lol

 

[Kooldino]

No problem.

 

[Nomad]

read the synth bottle.

"compatible with all motor oils"

 

[maxchao]

Ah! I guess that was a stupid question, I didn't read the bottle.
Oh well, that's good, save me some bucks

Josh

 

[MazdaSpeeder]

DIY semi-synthetic! (stooges)

 

[cantstopklze]

is not bad its just not going to be 100% synth eney more lol

 

[cantstopklze]

the stupides qeustion i herd ,was a guy that asked if u can put 15 tires on 16 mags!! stupid idiotlol

 

[Crazy D]

(boom07)

 

[maxchao]

OK, here comes another stupid question I always want to know the answer. Does the engine oil ever go 'bad'? Like...I can buy a 5 qt bottle and use most of it and let it sit half year and use it again....

Josh

 

[Crazy D]

This is all I could find on your question:

http://www.carkb.com/Uwe/Forum.aspx/subaru/3387/Motor-Oil-Shelf-Life

As noted it depends on the type and conditions such has been stored. Then again... I usually just use what ever is left for yard tools etc. in the summer so I've never thought about it.