Changing to synthetic oil query...

[Gards]

I'm sure this has been covered at some point but this forum is HUGE and would probarly take me ages to find the info I'm after.

Anyway I read a few months ago on a car forum that if your car has been using a particular type of oil, say a mineral based oil, you should stick with it and not change to synthetic as it is not compataible. Is this true, what does it depend on? What about if you do an engine flush?

I just bought a 97 Suzuki Swift GTI with 110000k's on the clock. I don't have the service history but its recent service had 15W/40 Castrol GTX3 put in which I think is labelled as being semi-synthetic from memory. When I go to change my oil I want to switch over to Castrol Magnatec 10w/40 which we all now is not a "real" synthetic. Would this be safe for my engine? Should I still do an engine flush? What about if I weant to change to a real synthetic like Redline? Does anyone have some good links to how to effectively and safely perform an engine flush?

I appreciate any input.

 

[wavinwayne]

Gards,

First off,

to BITOG.

1. "If your car has been using a particular type of oil, say a mineral based oil, you should stick with it and not change to synthetic as it is not compataible." - COMPLETE & TOTAL MTYH.

2. "What about if you do an engine flush?" - Short anwer is: "DON'T USE ENGINE FLUSHES!!!" They can quickly break up large pieces of crud, which can clog your oil pump pickup screen, thus starving your engine of oil & killing it.

If you want to "flush" the engine before switching to synthetic, just do several short OCI's with conventional oil. Then make the switch to synthetic.

The one exception to the "DON"T USE ENGINE FLUSHES" rule is Auto-RX. It seems to work very well for almost everyone who uses it. Do a search & you'll find tons of info on it.

 

[Gards]

Ok thanks alot for that info wayne, and for the big warm welcome.

I'm happy to be apart of this community and thankful such a useful and needed resource exists.

So it should be fine switching straight over from the GTX3 to the Magnatec without a flush (oil change method or Auto-RX)?

I myself imagine it would but don't want to take any chances with my sweet little engine and would rather ask the question than regret a mistake.

Cheers

 

[mikemc]

Wayne is right, this myth that you can't switch to syn in an engine that has always used dino is just that, a myth. The exception would be an engine that is already leaking oil. If I were to switch to syn, I would use Mobil1 since its one of the few true synthetics (group 4), that way I know what I'm getting for my money. One safe way to 'flush' the engine is to do a couple of short intervals with the synthetic.

 

[Triple_Se7en]

Using "full bottle" engine flushes on filthy, small crankcases (3.5 qts - example) will cause problems. However, if your engine is not a disaster & is a typical 4.5 quart variety, using half-bottle flushes works fine. Been doing it for 30-somehing years.... no problems & alot cheaper than Auto-Rx.

 

[Blue99]

I like the practice of running a short OCI, 500 to 1000 mi, with a 15w40 HDEO, in any higher mileage vehicle to insure the rings are free.

The high solvency & TBN of an HDEO will work on the ring pack & help free up deposits.

On the subject of switching to synthetics, here's a Link to Quaker State FAQ's for some additional reading.

 

[e30cabrio]

I have a 1990 325ic with 63k orig miles. by nature the M20 engine has noisy valves and as I am getting up in miles I felt I needed to look at the oil I was using (I have used GTX 10-40 since I bought the car in August of 1990) I called BMWNA and was told to use Mobil 1 5-30 even though I live where the temperature is never below 60 and often above 90. I contacted Mobil and was told 10-30 so I bought 5-30 since I will continue to change the oil every 3k as before. I now have even noisier valves and am concerned that I should have gone with 15-40 like I thought in the first place. I would really appreciate the benefit of you oil gurus intelligence as I am very confused. Thanks.

 

[lewk]

this situation you describe is not an abberation cabrio. I bought a used astro van w/129xxx mi.(4.3 ltr vortec)that was using 20w50.previous owner was from henderson, near las vegas. I expermented with st. 30w,5w30,10w30,15w40,and mobil 1 10w30, easily the worst thing I could have done to this van. It took a engine that consumed a marginal amount of oil (no top off between 4k oci) to a 1 qt or less between changes. the engine has a tick, tap,racket, noise that was never present prior to using the mobil 1.GREAT oil for the right application but I PERSONALLY feel one should only use pao type synthetics if operating at extremes in an environment,(racing,commercial,temp, etc) and entertain the IDEA of long drain intervals. uoa to determine fluid condition and finally by-pass filtration are a must. 15w40 may be a better bet than synthetics but i'd suggest you closely monitor your fuel mileage. if you see a dramatic change all other things being equal, follow the mfgr,s recomendation .

 

[Gards]

Do I really need to do an engine flush if I'm switching oils? My engine seems to be in good nic, fairly quiet, no leaks, doesn't seem to burn oil, idles fine, goes hard.

Btw thanks for that site Blue99, it's great!

[ May 30, 2005, 11:53 PM: Message edited by: Gards ]

 

[DaveJ]

I would say you don't need to do a flush. Just add your new brand and change it and the filter way sooner the first time then go to your normal OCI. I only do a flush on a dirty looking engine right after I buy it. Then one load of Delo400 for 1000 miles, change the filter and dump the oil. Then new Delo 400 @ 10,000 OCI. It works for me. DaveJ

 

[Steve S]

Why change?

 

[bighead]

I've heard M1 0w-40 cleans pretty good too. You could use that for a few OCI's.

 

[Gards]

quote:

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Originally posted by Steve S:
Why change?

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I decided im not going change to synthetic, im just going to change over to Castrol Maganatec because of its lower startup viscosity and better startup protection over the GTX3.

 

[Gards]

quote:

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Originally posted by DaveJ:
I would say you don't need to do a flush. Just add your new brand and change it and the filter way sooner the first time then go to your normal OCI.

---

Is the sooner oil/filter change still required or recommended if Im just switching to Castrol magnatec, not synthetic? I ask because I don't want to spend money on extra oil ect if I don't really have to.

I've been planning to do a compatability test on the 2 oils when I change btw.

 

[e30cabrio]

Thanks for the info, now I am more confused. I switched to Synthetic because BMW said I should, if it is not going to help though I see no reason to spend 4.00+ per quart when I can use 2.00 Castrol. What is magnatec? should I look at that.

I am getting a headache from this! lol

Thanks

While I am thinking about oil what about a 97 Acura 3.0 CL with 40k? it's almost time for a change there and also I have a 2004 Passat V6 which is at 3k & ready for it's first change. AAAUUUUUGGGGHHHH!

LOL

 

[Losiho]

quote:

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Originally posted by e30cabrio:
What is magnatec? should I look at that.

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Magnatec is known as Castrol Start Up in the North American market.

 

[21Rouge]

quote:

---

Originally posted by mikemc:

Wayne is right, this myth that you can't switch to syn in an engine that has always used dino is just that, a myth. The exception would be an engine that is already leaking oil. If I were to switch to syn, I would use Mobil1 since its one of the few true synthetics (group 4), that way I know what I'm getting for my money.

---

Dont tell my wife that I now read this site!

I need some reassurance here. Is it a myth that replacing the factory oil too soon with a synthetic can cause problems? Here is my story:

I have had a new '05 5 speed Pontiac Vibe (Toyota 1.8 engine) for about three weeks. The plan was to replace the factory oil with
Mobile 1 5W30 Supersyn. After approximately 1100 km (650 miles) (at that point there had been no noticeable oil consumption...looking at the dipstick) I couldnt wait anymore

and did the switch. What is the current thinking regarding such 'maintenance'?

 

[Bryanccfshr]

quote:

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Originally posted by Boxgrover:

quote:

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Originally posted by mikemc:

Wayne is right, this myth that you can't switch to syn in an engine that has always used dino is just that, a myth. The exception would be an engine that is already leaking oil. If I were to switch to syn, I would use Mobil1 since its one of the few true synthetics (group 4), that way I know what I'm getting for my money.

---

Dont tell my wife that I now read this site!

I need some reassurance here. Is it a myth that replacing the factory oil too soon with a synthetic can cause problems? Here is my story:

I have had a new '05 5 speed Pontiac Vibe (Toyota 1.8 engine) for about three weeks. The plan was to replace the factory oil with
Mobile 1 5W30 Supersyn. After approximately 1100 km (650 miles) (at that point there had been no noticeable oil consumption...looking at the dipstick) I couldnt wait anymore

and did the switch. What is the current thinking regarding such 'maintenance'?

---

You did no harm. You could have run the factory fill longer. But all is good in that 1.8l engine. Actually the engine is probably 99% broken in by that mileage anyway and synthetic will not hinder break in.(I would just run factory recomended OCI's for a couple of intervals if you forsee getting into the extended OCI game).


Nice car. BTW.

 

[21Rouge]

quote:

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Originally posted by Bryanccfshr:

quote:

---

Originally posted by Boxgrover:
I need some reassurance here. Is it a myth that replacing the factory oil too soon with a synthetic can cause problems?

I have had a new '05 5 speed Pontiac Vibe (Toyota 1.8 engine) for about three weeks.

---

You did no harm. You could have run the factory fill longer. But all is good in that 1.8l engine. Actually the engine is probably 99% broken in by that mileage anyway and synthetic will not hinder break in.(I would just run factory recomended OCI's for a couple of intervals if you forsee getting into the extended OCI game).

Nice car. BTW.

---

I appreciate the reply. Thanks.

I dont plan on extending the OCI...5k km I suspect.

I think the Vibe is unique in the GM lineup. The very intelligent use of space and the Toyota heritage sealed the deal for me.

 

[Bryanccfshr]

quote:

---

Originally posted by Boxgrover:

quote:

---

Originally posted by Bryanccfshr:

quote:

---

Originally posted by Boxgrover:
I need some reassurance here. Is it a myth that replacing the factory oil too soon with a synthetic can cause problems?

I have had a new '05 5 speed Pontiac Vibe (Toyota 1.8 engine) for about three weeks.

---

You did no harm. You could have run the factory fill longer. But all is good in that 1.8l engine. Actually the engine is probably 99% broken in by that mileage anyway and synthetic will not hinder break in.(I would just run factory recomended OCI's for a couple of intervals if you forsee getting into the extended OCI game).

Nice car. BTW.

---

I appreciate the reply. Thanks.

I dont plan on extending the OCI...5k km I suspect.

I think the Vibe is unique in the GM lineup. The very intelligent use of space and the Toyota heritage sealed the deal for me.

---

Yep, it is differnt from the rest of GM, It's a Toyota Matrix with a Pontiac fascia. But indeed the utility of the design is great.