thinking about switching to synthetic blend, 133k miles

[horvath]

Hi,
My oil change is due and I have been thinking about switching to synthetic, but then I read about high mileage cars and synthetic oil and I'm not so sure...

Should I switch to a synthetic blend? If so which one? Mobil 1/Castrol? What weight should I use? (I live in Missouri).

If I switch to a synthetic blend should I do the next oil change after the first 1500 miles? Could I eventually switch into synthetic only?

[geoff5093]

Dont mean to steal your thread, but my car also has 133K and as far as I know has just been using cheapo oil. So I would like to know as well if it would be a good idea to switch to synthetic or not.

From what I heard in some other threads, Mobil 1 states that it can be used in high-mileage engines without causing oil leaks.

[GaryS]

The switch to synthetic should not cause any problems. There are old wives tales out there about synthetic causing leaks but to the best of my knowledge, there is no scientific basis for these arguements. If you choose to go to synthetic, use the oil as specified in your owner's manual. Going from memory here but my 97 V6 takes 5W-30 and I use it year round.

One can make the perfectly valid arguement that ANY QUALITY OIL in the proper weight will perform as well as any synthetic, as long as normal oil change intervals are followed. I use Mobil 1 synthetic (I like it because it has been around a long time) in all of my cars except my classic Corvette. Oth, I have advised my daughter to use standard dino oil in car, just to avoid the price penalty of synthetic. For me, the advantage to sythetics are higher shear strength which means it resists breaking down under extreme conditions. That said, I am a fairly sedate driver but I still use synthetics. Another advantage is the ability to go to the manufacturer's recommended oil change safely, imho. For instance, in my daughter's car with a 7500 mile oil change interval, I go to 3000 miles and change the oil. In my cars with synthetics, I go up to the oil change interval.


Imo, if you switch to synthetics, you can run to your standard oil change interval. There shouldn't be any reason to do a shortened interval just to flush out the old dino oil. I have read that oils from different manufacturers should be compatible with one another. So if you have residual dino oil left in the engine and put synthetics in there won't be any adverse effects..

[geoff5093]

The manual says to change every 7500, but I go every 5000 since 7.5K seems like a while to wait, and it's easier to remember when to change when you change it at 130k, 135k, etc.

[horvath]

My car doens't have any leaks right now. So basically going straight to synthetic is the best idea. No need for a precaution of a blend. Looks like I will switch to synthetic Mobil 1.

Although Mobil 1 states no danger of leaks, it is not a warranty or anything so we need to be careful.
Anybody else can comment?

[GaryS]

Originally Posted by horvath

My car doens't have any leaks right now. So basically going straight to synthetic is the best idea. No need for a precaution of a blend. Looks like I will switch to synthetic Mobil 1.

Although Mobil 1 states no danger of leaks, it is not a warranty or anything so we need to be careful.
Anybody else can comment?

http://www.quakerstate.com/pages/carcare/whattoknow.asp READ the myths.

http://www-d0.fnal.gov/~jkrane/cars/synth_survey.html LENGTHY but it gets to the point.

http://www.aircooled.net/gnrlsite/re...s/synthoil.htm

So, what is the point? Use whatever oil you are comfortable with. Switching back and forth between synthetic and dino oil is fine. Don't take my word for it. Read from the experts.

[keba]

One against synth in high mileage (with a caveat)

I have a96 LE 165K ,and recently I changed to walmart 10-30Synth from their 10-30 regular.

There was a slow leak the nest day.However. ..

I found out that the previous owner had cheaped out and used a gasket maker type oil pan gasket than the OEM cork or whatever,and it was leaking from there.

maybe OEm would not have leaked...also ,it was leaking only when the motor was running and warmed up,it stopped after the motor cooled down.

Will update after I change the gasket this weekend.

keba

[mandyfig]

Synthetics work as good as traditional oil. Depends on frequency of changing and driving habits. But if you can afford to spend on synthetics and you feel better, go ahead.

[triggerhappy007]

Originally Posted by mandyfig

Synthetics work as good as traditional oil. Depends on frequency of changing and driving habits. But if you can afford to spend on synthetics and you feel better, go ahead.

Don't most synthetics work better than traditional oil?

[blackedcoupeLE]

On a previous car I had that had 130K, I switched to synthetic oil, and approx. 4000 miles later I developed an oil leak (whether or not it had anything to due w/ the oil, I don't use synthetics anymore)

[GaryS]

Originally Posted by triggerhappy007

Don't most synthetics work better than traditional oil?

What do you mean by "better". Read the URLs I posted and I can tell you that if drive normally (again, what is normal?) dino based oil is fine. I suggest that if you pull trailers, drive like a bat out of hell, live in an Arizon-like climate, then I would be using sythetics. For the 90% of us, dino oil is fine and meets all of the manufacturers requirements as specified using th API cagegory. That is the "SL" rating you see on the side of the oil containter.

http://www.calsci.com/motorcycleinfo/API.html

Fwiw, as I recall, Consumer Reports did an oil analysis and ALL the oils performed well with no differentiation between dino and synthetics.

[horvath]

synthetic blend would be a safe compromise and also work better?

[bigbird]

with my old camry, i switched to synthetic from regular at about 105K miles. this was before i know anything about cars and it workrd but the seals leaked a little. as it was explained to me. when u use regular oil it breaks down the seals and gaskets. when u switch to synthetic, because the molecules are smaller in synthetic then regular, it will leak through the worn seals and gaskets a little. i never lost a large amount of oil but i did have a dirty engine.

[djarno]

^ same here....i switched to synthetic at 85K miles...im at 100K now....my camry is leaking a tiny bit of oil but its nothing big....

[RningOnFumes]

I'm at 135k now. Swithched at about 95k when I first got her. Leaks enough to dirty up the engine, not much more.