Synthetic and Non-synthetic motor oil

[Victor_PR]

My car currently has Mobil 1 Synthetic oil in it. Since I have a pretty bad crank case leak, I have been refilling with the same type of oil. Until I can take the car for the leak repair , can I refill with normal non-synthetic oil? It is less expensive. I drive the car 80 miles a day.

Any thoughts?

Thanks!
Victor

[mr.vang]

throw in some thicker oil will also help with the leakage

[Victor_PR]

Could it be non-synthetic mixed with the synthetic that's already in the car?
Or do I need to do a complete oil change from synthetic to normal?

[DrJosh]

Do a complete oil change

[FLG]

Makes no difference but if you run the car its whole life on conventional and switch to synthetic the added detergents will usually clean any built up gunk around gaskets and cause leaks.

Sent from my Galaxy Nexus using Tapatalk 2

[mr.vang]

i have mixed synthetic and non-synthetic before and it doesn't seem to have any problem. some oil are half synthetic such as castro blend.

[jlevie]

Mixing synth and non-synth isn't a problem.

There is no advantage to running synthetic in an E30 and one disadvantage. The major advantage of synthetic is the slower rate of breakdown of the oil, allowing for longer oil/filer change intervals. An E30 should see the original change intervals, regardless of what oil you use. So the major advantage of synthetic is lost. The disadvantage is that these engines need high ZDDP content, which is very hard to find in a synthetic. Valvoline VR1 20w50 is the most readily available oil with reasonable ZDDP content. Brad Penn is better, but harder to find. Rotella T used to be good, but the word is that it's ZDDP has been reduced.

[Emre]

My car currently has Mobil 1 Synthetic oil in it. Since I have a pretty bad crank case leak, I have been refilling with the same type of oil. Until I can take the car for the leak repair , can I refill with normal non-synthetic oil? It is less expensive. I drive the car 80 miles a day.

You have no reason to worry. Synthetic and non-synthetic can be mixed without causing any problems at all.

Besides, Mobil 1 isn't really synthetic anyway: it uses a Group III (refined petroleum) base stock, as opposed to true synthetic motor oils based on Group IV (PAO) or Group V (usually, ester) stocks.

[stamar]

mobile 1 15 50 has enough zddp and it is a pao true synthetic

only mobil 1 5-30 and 10-30 are not true synthetics.

in fact its totally the opposite, almost all synthetics have enough zddp the oils that do not are all dino oil.


most 20-50 oils have enough zddp and all listed synthetics do.

at 1200 ppm mobil 1 15-50 is the perfect oil for an m20./

and of course there is the million mile ad where they used it.

still the same amount of zddp as the 80s.

valvoline full synthetic has more than enough zddp, and castrol edge.

whether or not your engine can keep oil clean long enough to have a longer oil change interval isnt known. even if you had the best oil in the world if your engine is worn it will get dirty too fast to matter.

mine makes it farther on full synthetic but not a lot.