What happens if you don't change your engine oil for too long?

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Evadman

Administrator Emeritus<br>Elite Member
Feb 18, 2001
30,990
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I bet when your brake light comes on, you pop the radiator cap and put a tube of toothpase in there.
 

Shawn

Lifer
Apr 20, 2003
32,236
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Originally posted by: Evadman
I bet when your brake light comes on, you pop the radiator cap and put a tube of toothpase in there.

Make sure to open it while the engine is still hot.
 

UNCjigga

Lifer
Dec 12, 2000
25,597
10,296
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LOL, my sister never changed the oil in over a year when she first got her Subaru. That was in 1998 (its a '96 model.) I'm driving it now and its got over 115k miles and still runs like a champ.
 

fbrdphreak

Lifer
Apr 17, 2004
17,555
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Originally posted by: phreakah
i did that on my civic ever since i knew i was going to trade it in.... didnt change the oil for about 15k and traded it in and got my new car... (which i do take care of)

ass
 

Dacalo

Diamond Member
Mar 31, 2000
8,778
4
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Originally posted by: phreakah
i did that on my civic ever since i knew i was going to trade it in.... didnt change the oil for about 15k and traded it in and got my new car... (which i do take care of)

That's so wrong.

My protege5 got oil changes every 3,000 miles, even though I knew well ahead of time that I was going to trade it in.

:heart: my G35 coupe
 

hemiram

Senior member
Mar 16, 2005
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My friend bought a great looking van, cheap, but about a year after he got it, it started leaking tremendous amounts of oil out of the valve covers, and the PCV line was corked up with oil and crud. The oil had sludged up and corked up the drainback holes in the heads, an when it was driven over about 25 MPH for any length of time, the oil started pumping out.

My friend teaches autoshop, and it was a great demo for what happens when you don't change the oil. The engine was sluged up tremendously, and he had his students yank it, and clean out as much crud as was possible and then run Mobil 1 synthetic in it, changing it after 3 days the first time, working up to 3 month changes eventually. The first change produced about a quart of sludge that the kids couldnt get out.

I saw less loaded up engines clean up with Mobil 1 myself, and the first oil change was amazing, you wouldn't think all that crap could come out just by changing the oil.

Another friend bought a 2 year old Ford F150 from some guy and as far as we can tell, the oil was never changed, period. Apparently, he thinks oil changes are an oil company "plot". There are kooks everywhere..
 

Apathetic

Platinum Member
Dec 23, 2002
2,587
6
81
Nothing will happen in the short term. However, you are seriously shortening the lifespan of your engine.

Dave
 

PricklyPete

Lifer
Sep 17, 2002
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yes you should. The oil gunks up and can eventually cause engine failure. Get it changed immediately.
 

BobDaMenkey

Diamond Member
Jan 27, 2005
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Sometimes nothing, sometimes VERY BAD THINGS. The oil will become sludge, which defeats the purpose of oil in an engine, which makes it a ticking time bomb. When you literally hear the engine ticking(or knocking) then you know you really screwed it up.
 

NiteWulf

Golden Member
Jan 3, 2003
1,112
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I went for 5k without a change in my truck. The oil gunked up so much it wouldn't start below freezing. It's since had 2 changes and runs great.

Has anyone tried that stuff that's supposed to dissolve the gunk? I saw it at the autoparts store last time I bought oil. Apparently you dump it in the engine, run for five minutes, then change the oil, and it gets just about everything out. I'm wondering if I should use it once or twice.
 

GrassR00t

Senior member
Mar 3, 2004
503
0
76
When I lived over in Okinawa, Japan. I had a Toyota Cielo that I only changed the oil in once the whole 3 years I was there. That car ran like a champ till the day I left.
 

TitanDiddly

Guest
Dec 8, 2003
12,696
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Milage goes way up, sometimes up to 150 MPG if you don't change it at all. You can get up to 340 MPG if you don't run any oil at all.

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