Will it harm my car if I have been using regular motor oil when I was supposed to be using synthetic?

Question

I bought my car from a private party who happened to be a mechanic. When I got it, he told me to "always make sure to use synthetic motor oil."
I'm not a dumb chick but I kept putting off some work that needed to be done (ie. replacing gaskets that were needed on the motor and oil pan) so the car was consistently leaking oil and I needed to check it and replace what had been lost about every 2 weeks or so. Well at some point down the line, on the spot and unable to obtain synthetic oil, I used regular motor oil that I bought at the gas station.
Maybe I AM a dumb chick because I kept putting off the repair work and again and again I found myself using the crappy oil which was easier to get when on the fly.
I'm not sure if this is the problem or not but the car is running crappier and crappier and I'm worried that I made a small problem much worse.
I'm really scared to take the car to this guy for the job and admit that I didn't take his advice.
What do you think,?

Answer 1

no harm was done by switching from syn to conventional. there are a lot of myths about that. you can use syn one change, then conventional next, then back to syn and it never hurt a thing.

Answer 2

Go with Synthetic, a good synthetic. Mobil1 is great. If you can get it, Royal Purple is about the same price and it's awesome. The above people that say to use regular must not have experienced Mobil1 or Royal Purple. In fact, if you want to have a fun test, get a car with atleast 60,000 miles and preferably older that has always had regular in it, and put in synthetic. You will literally hear and feel the engine run smoother. Less engine noise, better gas mileage and better performance. NOTE: Some people get oil leaks when they change from regular to synthetic. I changed 5 cars over to synthetic from regular and never had this problem - but it's allegedly a problem for some people. »J P.S. Check out my source, it's a very interesting page. Royal Purple actually smooths internal surfaces in the engine over time.

Answer 3

I think that putting off the needed repairs has contributed more to the problem than whatever kind of oil you're using. As long as it's a detergent oil, and of the proper viscosity (10W30 or 10W40) you're probably okay in that regard.
First you need to fix the leaks and change the oil filter, then find out why it's running "crappy." It could be something simple, like a dirty air filter, or a dirty gas filter, or it could be something more sinister, but i doubt it has to do with whatever oil you use.

Answer 4

The oil won't make it run bad, you need to have instalube or a place like that to change your oil, 15 min and youre out, even your busy schedule should accomadate that. Get it changed and then take it to him, whatever the problem is, it's not due to oil. I would reasses his mechanical skill if everything leaks, and starts running bad soon after purchase. I would't have put the expensive oil in with leaking gaskets either.

Answer 5

An old and damaged gasket erodes over time. I think that time and using the car made the problem worse. You should call car talk on public radio and ask click and clack to find out what to do, but you should probably change the gasket or seal it up with one of the gasket seal products available at the auto store. Do the quick fix if the car is old and means nothing to you. Change the gasket if it is a keeper.

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Answer 6

Crappy oil is better than no oil.

Depending on how long you waited to put oil in it is more of an issue than what kind of oil.

If you waited untill the "oil light" came on before you added oil, you probably did some serious damage to the engine.

Answer 7

I doubt using any modern motor oil will damage your engine. Synthetics are designed to run longer.
Go get all those leaks fixed, and don't tell what oil you use, just tell him to change the oil and filter with what he had used before.