Synthetic oil

Tiny
MMPRINCE4000
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  • ALL OTHER MAKES ALL OTHER MODELS
I have always liked and used synthetic oil due to its high temp capabilities and effective detergent capacity.

I have heard many times, even by mechanics that once you switch you cannot switch back? I have never got a definitive explaination as to WHY, or any imperical evidence.

I think this is a myth, any opinions, comments. Thanks Paul
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Thursday, August 20th, 2009 AT 2:24 PM

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Tiny
DR. HAGERTY
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Hogwash I say, probably started by some old timer that had a bad experience. What could be the downside, they take away your birthday?
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Thursday, August 20th, 2009 AT 2:33 PM
Tiny
KHLOW2008
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Agree with Dr.

I on the other hand don't recommend synthetics to my customers. Simple reason, regular oil change would get the engine running for its worth as most people don't thrash their vehicles.

I have come across some vehicles that do not agree with synthetics. Quite a number of Mitsubishi engines with hydraulic valve lifters experiences lifter noise when synthetics were used and customers were advised by dealers to use only mineral based.

The only advise I always read about synthetics is to start using them when engine is new. When engine gets older and oil consumption increases, that is the time you have to consider changing to mineral based as synthetics do not have higher viscosity grade.
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Thursday, August 20th, 2009 AT 4:56 PM
Tiny
MHPAUTOS
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My 2 bob's worth......

I have had over the years a number of cars (and here as well now) that have experienced oil burning after switching to synth oil , when returned to mineral based oil this has immediately cleared up, it was always said that you can't run in a new engine on synth, and if used after the run in you cant switch back, now i have never seen the science on this, but it dose seem to be rule of thumb rather than the exception for a number of cars that i have had problems with over the years.

I did a post here not that long ago, with this result and a glowing thank you from the member for fixing his problem, he had no idea that this would be the case either.

http://www.2carpros.com/forum/1992-audi-100-car-smokes-now-vt300415.html
His post when he voted.....

gave me some awesome advice that completely fixed my problem! Amazing! and recommended

Mark in Aust.
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Thursday, August 20th, 2009 AT 10:21 PM
Tiny
MMPRINCE4000
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Thanks for the input guys. Paul
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Friday, August 21st, 2009 AT 1:41 PM
Tiny
MMPRINCE4000
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An ASE Master Tech was the one who said that you CANNOT switch back to conventional oil once you have used synthetic. When I ask why, he just said "everybody knows that" (no reason).
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Saturday, August 22nd, 2009 AT 2:42 PM
Tiny
BLACKOP555
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Synthetic a no no for breaking in an engine. The rings need a bit of wear so they can seat in properly. Synthetic is juust toooo slick. Old synthetic didnt have petro in it I belive. And when switched to that the seals would shrink causing oil and smoke like in your topic you posted mark. Till the old petroleum oil went back in there and swelled the seals back up.

I cant see any harm of switch to synthetic and using it then going back.
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Saturday, August 22nd, 2009 AT 3:07 PM
Tiny
DR. HAGERTY
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It's a government conspiracy.
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Saturday, August 22nd, 2009 AT 3:24 PM
Tiny
KHLOW2008
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I remember way back in 1991 when the legend was to be launched in Malaysia, the Jap were worried when synthetic oil was proposed by the distriutor.

They were asking if oil selas that were Teflon and non-Teflon based would be affected. I guess that was what blackpo555 mentioned about seals shrinking.

I believe we have passed that stage whereby oil seals are no more a concern to different oils.

Personally I don't see any logic why swapping is not allowed. The one thing that is taboo to me is oil treatments. Would kill the engine faster than anything else.
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Saturday, August 22nd, 2009 AT 3:34 PM
Tiny
MMPRINCE4000
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Having used a synthetic in a turbo engine for years, I was amazed how clean the upper engine was upon disassembly, not a spec of varnish or sludge, and as you all know, turbos can get VERY hot.
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Sunday, August 23rd, 2009 AT 1:26 PM
Tiny
KHLOW2008
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For Turbo engines I would recommend synthetics. I was thinking all along the lines of normally aspirated engines. ;)
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Sunday, August 23rd, 2009 AT 10:48 PM
Tiny
MMPRINCE4000
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Or any engine that is under severe stress, taxi, police, towing. Paul
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Monday, August 24th, 2009 AT 11:54 AM
Tiny
RACEFAN966
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Ok coming from the standpoint of a performance engine builder all I use is sythetic. Now you can not use sythetic untill you have 5000 miles on the engine after a rebuild. However the more important thing is the lack of ZINC or ZDDP in today's oils and what that does to non roller cams. That is why I use a zinc additive in all the flat tapet cam engines I build with out it I know it just a short time before the cam and or lifter will fail.
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Tuesday, August 25th, 2009 AT 5:37 PM
Tiny
SERVICE WRITER
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ASE certification equals good test taker. Maybe more.

I have switched on mine. Switched to it for 30,000 then away from it since. No problems.

For the cost I don't recommend it. I do think it's better. But Budweiser works as good Guiness does.
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Wednesday, August 26th, 2009 AT 2:21 PM
Tiny
RACEFAN966
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There is no problems switching to and from synthetics. I have customers that do this with no problems. Now I did put Royal Purple in my car and did a dyno at the time and guess what 8hp gain so synthetic can make a difference in friction or there would be no gain. Just a thought.
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Wednesday, August 26th, 2009 AT 3:43 PM
Tiny
MMPRINCE4000
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Yes as racefan966 said, I have seen dyno results with the only difference was conventional oil to synthetic and it showed small HP gains, 9hp in a 383 Chevy smallblock.
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Thursday, August 27th, 2009 AT 12:54 PM
Tiny
SERVICE WRITER
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Cool stuff guys! Glad it came up.

Why is that?

I had a customer that had a 85 caprice and had always used syn. HE ended up with it at a demolition derby and the rad got knocked open, lost the coolant. He had kept going util he got hung up or something. Afterwards he had started it back up in the pits and wanted to see how long it would take to blow it up. I honestly can't remember how long but he had it full throttle for a fair amount of time and ended up having to shut it down by the track officials so it never blew.

I have heard that the engines do stay clean inside, but for the average person. Is it worth it?

On 100,000 miles there are possibly 33 old changes done and at an additional cost of $25 per change
comes out to $833. So they run it that long then switch over to conventional. Would that sound like good insurance?
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Thursday, August 27th, 2009 AT 10:45 PM
Tiny
RASMATAZ
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We should be learning and familiarizing the ( CAN ) diagnostics this is what's happening in lieu of liquid engineering technology,this is my 2cts.

Any fully qualified expert on it I'm willing to learn more on it the heck with the slippery stuffs.


http://www.2carpros.com/forum/automotive_pictures/12900_auto_networks_1.jpg



Good day Gentlemen

rasmatics at work
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Thursday, August 27th, 2009 AT 11:36 PM
Tiny
SERVICE WRITER
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Throw in Mode 6 too while your at it Raz! It's like reading bloody Greek.
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Friday, August 28th, 2009 AT 12:28 AM
Tiny
RASMATAZ
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That's right amigo its one of them and I'm getting bald trying to figure it out myself I think I need to go back to school to refresh my half watt PCM. But by the time it fully locks in place I'll be gone, right now am on borrowed time.
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Friday, August 28th, 2009 AT 12:32 AM
Tiny
KHLOW2008
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Hey Jess,

Nope, I don't think you are on borrowed time. If it is, how are you going to pay back?

Just take it as a bonus from above ;)

Don't know what mode 6 is and CAN = sardines.
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Friday, August 28th, 2009 AT 12:03 PM

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