Oils aint oils

BillC · 17-04-2009, 11:22 AM

On my XR6 which has done 185,000 Ks. I am toying with the idea of putting full synthetic oil in on my next oil change. I have only done 5000 of the Km so I am unsure of its history as to what type of oil was used. I have bought engin flush so I intend to do that prior to the engin oil change.

In my younger days I recall hearing that if a car was on mineral oils for a long period and you change it to synthetic (or the other way around) you can cause damage to your engin.

Is this an urban myth ? Will it cause damage ? Is it worth changing ?

Mr Hardware · 17-04-2009, 11:42 AM

I have heard a similar thing too. I think the go is to go from mineral to semi-synth to syth, if you so desire.

GK · 17-04-2009, 02:26 PM

Quote:

Originally Posted by BillC

On my XR6 which has done 185,000 Ks. I am toying with the idea of putting full synthetic oil in on my next oil change. I have only done 5000 of the Km so I am unsure of its history as to what type of oil was used. I have bought engin flush so I intend to do that prior to the engin oil change.

In my younger days I recall hearing that if a car was on mineral oils for a long period and you change it to synthetic (or the other way around) you can cause damage to your engin.

Is this an urban myth ? Will it cause damage ? Is it worth changing ?

Urban Myth. You can use either mineral or synth oil as long as it's the right grade etc.

BillC · 17-04-2009, 03:01 PM

I googled mineral oil to synthetic oil and it mentioned in the discussion that older oils synthetic to mineral had different effects on seals and gaskets. So they said that if you changed from mineral to synthetic you would have problems with seals and gaskets leaking. They say that with the new oils this is no longer an issue.

I think I will change to synthetic this weekend.

Mr Hardware · 17-04-2009, 03:38 PM

oh ok, i'm glad my information was at least once right! semi-synth is the sweet spot however.

dreadly · 17-04-2009, 03:51 PM

Best oil is Ford 15w-40 ;) Try it first, pick up from ya local dealer

Mr Hardware · 17-04-2009, 04:04 PM

Yeah 15w40 is king for the AU I6.

Erich · 17-04-2009, 08:18 PM

I just use Magnatec - pretty sure thats the good stuff anyway - semi?

dreadly · 17-04-2009, 09:26 PM

Dont use magnatec

ams77 · 17-04-2009, 10:02 PM

why not magnatec, ford uses 10w-30 semi synthetic magnatec.

toolchick01 · 17-04-2009, 10:30 PM

I have found that in some cars, magnatec comes out like water when you do your oil change. And from memory 15w40 is recommended for AU's. BA's are 10w30.

dreadly · 17-04-2009, 11:12 PM

Like what toolchick01 said... it's comes out watery... and a weird colour.
Also the magnetic bonding stops any loose particals from falling into the sump, hense not coming out with your oil change. Ive tried it imo it wasnt good and i wont do it again. Always Ford 15w-40 it's awesome stuff been using it for 3yrs no dramas what so ever. ;)

Mainlube · 18-04-2009, 06:46 AM

One of the major things that will shorten the life of an older engine is sludge built up which can block the gaps in the oil rings and stop their ability to scavenge oil back to the sump off the bore.

This will give a symptom of a stuffed motor before it actually is.

At this mileage I would start flushing at each oil change and run the Edge 10w60, which is a PAO synthetic (not an ester that can effect seals)

Time to start using better and cleaner oils if you 100,000's more klms out of it.

I'm at the LS1 Nats at present, when back I'll post a paper on how to flush your car your self from front to back.

Cheers

Steve

Erich · 18-04-2009, 02:40 PM

Steve

Cheers - looking forward to it - also "recommendations" for a semi synth oil for an AU III with 72 - all stock atm

Mr Hardware · 18-04-2009, 05:00 PM

Castrol FMX 15W40 semi-synth is, i believe, the best AU I6 oil around. It's a damn shame you can't buy it over the counter, it's workshop only. So in that case Castrol GTX3 Modern Engine 15W-40 is the best.

Erich · 18-04-2009, 05:51 PM

Quote:

Originally Posted by Mr Hardware

So in that case Castrol GTX3 Modern Engine 15W-40 is the best.

Thankyou. Ive just got the car so it will be interesting to see how the oil drains next week. Will wait and see how Steves method of flushing compares to mine ;)

AUbigfoot · 18-04-2009, 06:38 PM

I'm also keen to see this write up. I'm sure it will be a great help to a topic that has so many answers!

Cheers!

Erich · 18-04-2009, 08:23 PM

anyone have anything solid on Magnatec not doing its job? Im a mechanic and thats not what I see

:

**SSD-85** · 18-04-2009, 09:31 PM

I am having the same predicament with my xr8, it's now due for it's first oil change since i bought it. And the last change had F@#kin magnatec put in it :(. I used to put gtx2 10w30 in my vct (since that was the oil type it said on the filler cap hehe), as for this, well i could just go with the recommendation again, but like BillC i am also wondering.....

GK · 19-04-2009, 12:01 AM

Quote:

Originally Posted by Erich

anyone have anything solid on Magnatec not doing its job? Im a mechanic and thats not what I see

:

My objections to Magnatec were that my engine was quite rattly. It also came out very watery.

GK

Erich · 19-04-2009, 12:33 AM

The new oil you changed to made a difference there? what are you using now?

Im always up to see what works

V8 EF Fairmont · 20-04-2009, 06:12 AM

Old man had an EF V8 Fairmont, used Magnatec religiously every oil change. Car blew a head gasket at 200,000kms and mechanic said that everything was like new inside. Thats been good enough for me to use it.

Also, I assume if you're using a flush, that will remove anything Magnatec holds in the engine?

BIGJB · 20-04-2009, 07:01 AM

I was a Magnatec fan for a long time but have now changed to Edge.
I have noticed that when you are giving the car a reasonable amount of stick
and holding high revs for a period of time Magnatec must become very very thin because
the oil pressure drops to a disturbingly low level. Hence the reason I no longer us it.

Mainlube · 20-04-2009, 08:35 AM

Quote:

Originally Posted by Erich

Steve

Cheers - looking forward to it - also "recommendations" for a semi synth oil for an AU III with 72 - all stock atm

Erich

Sorry I don't have much experience with semi synthetics so you may have to see what other posters say and suck and see.

Cheers

Steve

PS. I'll get that flushing paper up this week.

Erich · 20-04-2009, 08:38 AM

Steve - I happy to also at full synth as well - I eye always open they say ;)

Erich · 20-04-2009, 08:39 AM

Quote:

Originally Posted by 99GHIA

I have noticed that when you are giving the car a reasonable amount of stick and holding high revs for a period of time Magnatec must become very very thin because
the oil pressure drops to a disturbingly low level.

That is disturbing for sure - I think I will add an oil guage for a bit to monitor as this is a good point!! cheers

GK · 20-04-2009, 06:08 PM

Quote:

Originally Posted by Erich

The new oil you changed to made a difference there? what are you using now?

Im always up to see what works

Yep!

I tried Penrite HPR 10 Gas. That worked well. I've also given Pennzoil a very good run. That also worked well, but now my SuperCheap don't stock it.

I've decided to give the Shell Gas 15W/40 a run, as the Penrite was a little expensive, and I change the oil at 5,000 kay intervals.

GK

womble101 · 20-04-2009, 08:19 PM

The wife and I run full syn nulon oils in our 6 & 8. Never had a problem, the 6 has done 160K+ and the 8 105K

rob_liss_lms10 · 20-04-2009, 08:51 PM

I use Royal Purple 10x40, love it, comes out looking like previous oil I used to put in brand new after 5000k. Won't use anything else now.

ronwest · 20-04-2009, 10:49 PM

Tech Resources has an interesting comparison of semi-syn/syn oils:-

http://www.fordforums.com.au/vbporta...article&id=333