Switching to synthetic questions.answers

So if anyone hasn't seen my other post..I'm doing an engine swap. A SC series II from a Pontiac 100xxx miles and have no clue if itwas running conventional. Blend. Or synthetic... I know I want to run synthetic as innebraska we havepretty hellish winters and I know the pour temp and viscosity at these temps is a lot better... like four fold.. my question is..
Can I just switch to full synthetic after my engine is put back together... some people I know said "it depends on theengine" "you'll throw a rod BC the engine isn't used to full synthetic" "I need to do an oil change every 1000 miles for 5000 miles " "you need to gradually switch and run a blend for 3 oil changes" what is the truth here or who is right... ivebeen on bobistheoilguy.com and that just left me with more questions than answers. Does anyone know with these engines... can I just switch to full synthetic or do I have to break it in? Anyone do this before? Or know about switching from conventional and thebenefits of synthetic?

wee-one wrote:

So if anyone hasn't seen my other post..I'm doing an engine swap. A SC series II from a Pontiac 100xxx miles and have no clue if itwas running conventional. Blend. Or synthetic... I know I want to run synthetic as innebraska we havepretty hellish winters and I know the pour temp and viscosity at these temps is a lot better... like four fold.. my question is..
Can I just switch to full synthetic after my engine is put back together... some people I know said "it depends on theengine" "you'll throw a rod BC the engine isn't used to full synthetic" "I need to do an oil change every 1000 miles for 5000 miles " "you need to gradually switch and run a blend for 3 oil changes" what is the truth here or who is right... ivebeen on bobistheoilguy.com and that just left me with more questions than answers. Does anyone know with these engines... can I just switch to full synthetic or do I have to break it in? Anyone do this before? Or know about switching from conventional and thebenefits of synthetic?

don't know what you "should" do -- here is my thinking.

There is no way to tell, because you don't know the operating history or characteristic of the engine you are swapping in. Theoretically there's no problem switching t synthetic.

Just the same, when you have that pontiac engine out consider replacing the seals, they are easy to get to when the engine is out. That way you won't have oil leaking past the external seals. And consider replacing the oil pan and valve cover gaskets. If the car was ever jacked up by its oil pan that gasket will leak (it's sort of a crushing type). Easy to do while it's out of the car.

Albertj



A good synthetic (Mobil 1, for instance) would not be the proximal cause of a problem if the engine is sound.

A synthetic that is really modified dino oil (WalMart, Pennzoil, Valvoline) would not

Anything you hear or anything anyone has told you about switching to Synthetic oil is a lie, a myth, a farce, etc etc. You can put 2 quarts synthetic and 2-1/2 quarts conventional if you want to, it won't hurt a thing.

You can run full synthetic, then switch back to conventional if you want to. As long as the weight of the oil is same, it doesn't matter. The whole "gradually work it to synthetic" is absolute nonsense. The person who told you that needs to be educated.......

Abaddon wrote:

Anything you hear or anything anyone has told you about switching to Synthetic oil is a lie, a myth, a farce, etc etc. You can put 2 quarts synthetic and 2-1/2 quarts conventional if you want to, it won't hurt a thing.

You can run full synthetic, then switch back to conventional if you want to. As long as the weight of the oil is same, it doesn't matter. The whole "gradually work it to synthetic" is absolute nonsense. The person who told you that needs to be educated.......

I fully back up everything stated.

my riv has been using dyno oil its entire life (180k miles), 100k of that with increased boost...and i drive it like i stole it.
i burn+leak maybe 1/3 if a qt between changes(3k miles)

If you really want to know whats in the oil send a sample to Blackstone for analysis. they can tell you what it is.
then maybe after driving the car 6mo or so send another analysis to see if you have any unusual wear or are leaking anything.

Abaddon wrote:

Anything you hear or anything anyone has told you about switching to Synthetic oil is a lie, a myth, a farce, etc etc. You can put 2 quarts synthetic and 2-1/2 quarts conventional if you want to, it won't hurt a thing.

You can run full synthetic, then switch back to conventional if you want to. As long as the weight of the oil is same, it doesn't matter. The whole "gradually work it to synthetic" is absolute nonsense. The person who told you that needs to be educated.......

X2, there is more nonsense out there about synthetic oil than anything else. By law, all motor oil must be compatible. Synthetic oil, is oil. Oil that is engineered with the best molecular structure. Synthetic oil flows better at all temperatures, and keeps it's viscosity better at higher temperatures. Synthetic oil will live at temperatures that would turn conventional oils to sludge. Because it flows better, you MAY notice more seepage past seals and gaskets. You can go back and forth between synthetic and conventional oils, or mix them if you want, with no adverse effects at all.

Cool. Good... because another thing I heard is that it might foam up... thus preventing proper lubrication of the main bearings....

Oh... and I am replacing every gasket except the head gaskets... it'll just cost too much in labor... and I've also read that synthetic will leak for the first couple thousand miles but nothing too drastic.. and if it persists it just means the seals and gaskets are bad to begin with....
I know in cold starts it is ALOT better for the engine and battery since this is where 90% of engine where comes from where there is virtually no upper engine lube at all.... plus synthetics will travel much quicker to these areas...

Well... I'm just gonna do the switch then and to be safe do an oil change at 5k miles.. I'm using Pennzoil ultra with the hyper cleaning... what Ferrari fills their cars with in the factory.. what chiltren racing uses in NASCAR.. and close to all formula one cars.... it is also supposed to increase HP due to decreased sludge.. proper cylinder lubrication.. and quicker valve timing... not to mention it will properly lube the timing chain... I've done quite a bit of research on this and it is up there with ansoil...

For what it's worth, here's my experience:

- When I first bought the car, I used dino oil;
- Then I used Mobil 1 7500-mile syn-blend a couple times;
- Most recently I used Castrol's latest and greatest 'Edge' (which of COURSE, has already been reformulated...)
- I've had no issues with seals/leakage.

I have to wonder about that Edge's first formulation, because:
- My recent oil analysis showed higher than normal wear, with some indication of coolant contamination, but,
- My coolant recovery tank is moving an an undetectable rate;
- At 60 degrees, this full-syn 10-30 pours like straight 30-weight... and this seems to be born out by the fact that (unlike the usual claims,) my oil consumption this last time was the lowest I've seen - about 0.8 quarts in 4,000 miles instead of the usual 1.25 quarts...