How bad is it to not change the oil?

[turbonium959]

I would not say that going 9K without an oil change will damage anything, but it certainly could. I bet that car's performance is much worse. Change oil asap, add some sort of additive to it. At work I used to add some additive into the engine before the oil was drained, run it for 5 mins, and then drain it.

[Mark 02dx]

Back when I was working at a garage, we had a guy who bought a then-new 1996 Lumina to use as a taxi. I guess he didn't read his owner's manual (or couldn't; the guy barely spoke English), and didn't know he even had to change the oil.
Well, at about 30k (car was only 6 months old! Taxi drivers use the **** out of their cars) the engine started knocking, and he brought it in for us to look at. (obviously didn't understand the concept of "warranty", either, not that they would have covered it...) The dipstick was jet-black and kinda gooey. I pulled the drain plug and NOTHING came out. So we pulled the pan. There was about two inches of sparkly goo in the bottom of the oil pan. Pretty, but not a good sign.
I let my boss handle the guy after that, and he demanded that we clean out the goo and refill it with fresh oil. Okay, buddy, whatever...It's your car... We scrubbed out the pan, reinstalled it, replaced the filter, filled it up, and started it. Now there was REALLY a knock. But the guy seemed satisfied. He drove off, smoke pouring from the tailpipe and engine sounding like a rock tumbler.
The next day he called us for a tow, after it threw a rod.
Going 9000 is probably okay. But man, you should see what 30,000 in stop-and-go can do...

[Chad]

850,000 Miles hahahah wow never thought anything like that was possible.. but then again u did say it was a mazda ...

[92_2_fast]

The thing you have to realize is that the designed function of oil is to clinge to parts. By running the oil for so long you have filled every thing with Grime/laquer particles. What I would recommend doing is getting a cleaner chemical. Usually they are just thinned diesel fuel, pouring it in the crankcase and running it for twice as long as it says to, than change the oil. If you can find "winn's" products they work the best. Chances are if you go to a mechanic shop, they could hook you up. Try a firestone. Most of them have contracts with winn's.

[darkangel]

if its an ECO tech then get the filter at the dealer. as far as i know, no one else has that filter. its bad too not change the filter on twin cam engines regularly, hopefully there isn't a knock now. try too flush it out as good as possible cause those engines need it. i had a twin cam 2.4, and you can tell when it needed a change, the eco isn't any different. my girl has one. didn't her oil light come on??

[Kevin]

doesn't luckas make a cleaning agent you can throw in to scrub out your engine? i heard a few people suggest running a quart of ATF fluid with the normal oil change and after 500 miles changing the oil and the filter to straight motor oil? i don't know.. just another moronic "i swear it works" kind of stories, but hey, who knows
kevin

[Wombat]

Here's a crazy story for you about not changing oil. The guy who owned my Protege before me was the second owner and never did a bit of maintenance on it during the over 50,000 miles he put on. The brakes were worn so far that the brake light was on solid, the anti-freeze was brown and chunky, and the oil was filthy as you can imagine. Here's the really crazy thing about it, I had to pry the hood open to even check it out because there was so much rust on the hinges that the hood wouldn't budge when I pulled the latch! Thanks to the obvious lack of maintenance I was able to get the car incredibly cheap for that time. I got the car right at 100,000 miles, it now has over 170,000 and it's surprisingly running quite well.

When one of my cousins who is a mechanic was dating the lady who is now his wife she owned a Honda that had over 100,000 miles and she had never changed the oil because she thought all you do with a car is put gas in it. He changed the oil as soon as he found out about it and then the engine blew up!

[Kevin]

any amount of not changing your oil.. synthetic oil or conventional, is not good if not changed after 3,000 to 5,000 miles. the longer you leave oil in your engine, the dirtier it will get. the dirtier the oil.. the less effective the oil is at lubricating your engine, not to mention the wear the particles can cause on moving parts and blocking oil passages. what i would suggest, is an oil burning/leaking modification like i have done in my mercury sable (seriously, it's my lack of maintaining my car). the faulty oil pan gasket leaks so much oil.. i'm changing the oil entirely every 3 months, dumping in 3 to 4 quarts, but luckily, only putting 2,000 to 2,250 miles on the engine between oil changes. needless to say, she's lasted me 9 months
kevin

[jnorion]

Nice to hear you got such a long lasting reliable car, Kevin... 9 months on a Sable is pretty good

[Phyfer]

Hey, Im new here.... but I have a testimony.... my 91 Mazda Protege 1.8L DOHC With 226,657km on it is curently @ approx 10,000K since my last oil change (not exactly sure, speedo cable was broken for about a month) it was with Mobil 1 5-30 Full Synthetic. I check my oil regularly, not only is my oil still slightly golden, but it has no particals in it what so-ever. I've had the car since 112,000km and it was a lady that followed the maintenance that had it b4 me. Im switching to AMSOIL shorlty here, full change over (Air filter, oil filter, fuel filter, series 2000 synthetic oil, and synthetic gear lube for the 5spd), I will let you know how it changes the cars performance.

Im getting 35 or so US MPG right now in 1/2 city 1/2 hwy driving, we will see if the proclamations of AMSOIL are correct.

[pseal]

My 96 Owners Manual recommends an oil change interval of 7,500 miles, so 9,000 isn't all that bad; I've gone that long before, but not any further. Still running strong at 183,000 miles.

[mazdaboy1974]

I hated my 91 corsica so much i refused to change the oil for 2 years and it did not die .

[jnorion]

Guys. This thread is a year and a half old. The car has been gone for a long time. Let it die.

[goldstar]

Closed.