I have heard that once you go synthetic blend, you should not go back to conventional

well what if you go synthetic blend to full synthetic? can i go back to synthetic blend if i want

[knows nothing about cars, just how to change the oil]

12/14/2007 10:53:13 PM

just pick one and stick with it. The only time I've heard of switching blends is breaking in an engine with conventional, then switching over to synthetic.

12/14/2007 11:13:11 PM

well the first time i changed the oil, i used ford motorcraft synthetic blend 5w-20

well i go back to buy more and they didnt have any, so i bought pennzoil full synthetic


should i be alright to put the full synthetic in?

12/14/2007 11:52:24 PM

changing for one oil change isn't going to hurt anything.

12/15/2007 12:04:46 AM

you can change back and forth all you want. the only thing that could potentially happen is the detergents may remove crud that is blocking a potential leak (ie, it may start leaking if you switch over to full synth).

12/15/2007 2:35:22 PM

^exactly. you'll hear a lot of misinformation on how synthetics caused a leak but it's just not true. like ^he said about the detergents and the fact that you may have already had a leak but the conventional oil is just not reaching it. you can switch back and forth all you want. don't know why you'd want to. it's not like you'd be able to tell a difference by the butt dyno. however, it is proven on an actual dyno that the use of synthetics does add horsepower. they also provide better protection so again why switch back?

12/15/2007 2:44:46 PM

basically here is my synopsis

it is a 2007 Mustang GT, bought brand new in July
dont know what oil they started it off with (conventional or syn blend or what)
when i changed oil at around 6500 mi i put in syn blend
now 4.5k mi later i was gonna buy the same stuff, but walmart was out, so i got full synth pennzoil

i would like to switch back to the syn blend next time and thereon out. so will that hurt anything to do that?

12/15/2007 4:21:17 PM

no, it won't hurt a thing.

but personally i would put in some mobil1 and call it a day for 10K miles. plenty of cars come factory fill with mobil1.

12/15/2007 4:23:56 PM

http://www.amsoil.com/storefront/default.aspx?zo=1160837

12/15/2007 8:39:04 PM

dude, you have a mustang GT, don't be cheap. I would just use full synthetic on it.

12/15/2007 11:26:49 PM

doesn't matter what you use. havoline? pennzoil? whatever. just remember to change it properly.
------------------------------
amsoil is sketchy as hell. there is a real world test out there that shows amsoil thickening up over time.

that's not cool.

i'd use something else, hell anything else, that doesn't look/walk/act like a scam.

mobil1 is cheaper and works just as well.

12/16/2007 1:19:30 AM

im not trying to be 'cheap' i just keep reading that full synthetic causes some sort of leak and i dont know anything about switching between the types, other than keep a consistent 5w-20 rating

12/16/2007 2:37:01 AM

^^ I also know a guy who ran it for 25k, checked it every 3, and came out fine at the end.

12/16/2007 3:50:48 AM

With no more miles than you have on that car, I would say the probability of leaks developing is very, very slim. The leaks happen when someone decides to switch over to synthetic when a car is several years old and has many thousands of miles. Autozone carries motorcraft oil and filters too, in case walmart is out again next time you need to change the oil.

12/16/2007 2:38:34 PM

^^ was that verified by oil analysis?

12/17/2007 10:08:29 AM

i ran my civic for 10K miles with 5w20.

of course it wasnt the smartest thing ive done before. but it came out fine also

12/17/2007 10:22:06 AM

7k on penzoil full synthetic so far, hoping to stretch it to 10k.

12/17/2007 10:54:18 AM

yeah ive switched to Motorcraft...

IN MY CIVIC ahaha

12/17/2007 11:07:43 AM

shit, i run mobil 1 for 25-30k with no problems on a 210k motor

12/17/2007 11:33:12 AM

I usually try to change it after 10K and before 15K... usually I find time somewhere in there.

I laughed like hell at the guy I bought the car from saying he changed the oil every 2500-3000 miles (and used mobil1 synthetic) He wouldn't believe me it was a waste of $$

12/17/2007 11:39:21 AM

how much oil goes into your car?

12/17/2007 11:49:03 AM

As has already been said, synthetic does not cause leaks. It tends to "find"/exacerbate leaks that are already present on older engines. I switched to synthetic on a 8 year-old, ~55k mile car (my old Mark VIII) and it worked great, no leaks. Should cause you zero problems on such a new car. Considering the extended intervals (I'm paranoid, even with synthetic I change at 5K, but that only equals to about every 4 months for me) and the fact that it is a superior product, I'd stay with the full synth if I were you.

12/17/2007 2:06:54 PM

By checked it every 3k I mean he took a sample and sent it to an oil analysis lab.

12/17/2007 3:19:21 PM

cool.. did he use blackstone or is there somewhere else i dont know about (local?)

12/17/2007 4:03:41 PM

He lives out in california so i'm not sure where he did it.

12/17/2007 4:44:14 PM

where the hell is slownig? this is his bread and butter, he does like 400 oil changes a day, and fucks up 399 of them

12/17/2007 9:13:41 PM

12/17/2007 10:03:16 PM

he's about as useful as a torx bolt

12/17/2007 10:53:18 PM

12/17/2007 11:25:26 PM

Quote :

"dude, you have a mustang GT, don't be cheap. I would just use full synthetic on it. "

How did everyone miss this gold quote, lol

12/18/2007 8:25:09 AM

Quote :

"but personally i would put in some mobil1 and call it a day for 10K miles. plenty of cars come factory fill with mobil1."

Mobil One's the way to go. And I didn't start using full synthetic oil in my car till around 180k miles, and have never developed any leaks.

12/18/2007 1:15:17 PM

So what IS the truth behind the "never use synthetic in high mileage motors" theory? Is there any merit to it at all? How, in any way, can synthetic be more harmful than regular oil (besides cleaning out stopped leak areas).

12/18/2007 9:00:11 PM

^umm, how about no. Better in every way, well except for the price. I have 265k miles on my engine and drive the snot out of it. It burns no oil. I don't need any more convincing.

12/18/2007 10:05:51 PM

Before I built the stroker in the jeep I swapped to synthetic @ ~120k miles. No problems whatsoever

12/18/2007 10:18:20 PM

as long as you have maintained your car you can switch to syth at 10209214820984 miles.

if you treat it like crap, then it may have build up.

same goes with seafoam type agents, then get rid of all the buildup.

12/18/2007 10:54:04 PM