Anyone ever have knocking with synthetic oil.

[Gl-boost]

I just recently switched to full synthetic(in my GL-10 turbo) and know when I start up from a dead cold start in the morning I hear a slight tick. I know these commonly get ticks but I din't remember it with regular oil. I am running 10-30 full castrol synthetic and did notice when putting the oil in at the change that it seems thinner than regular oil. It stops after a minute or less when it warms up a bit. I just wanted to know if anyone has experienced this.

[Subarian]

I have a similar problem running synthetic in my Isuzu Rodeo. The only thing I can figure is that the oil pump is too worn and the synthetic is too slick for me to get good oil pressure. There's a significant difference in oil pressure between the same grades of dino oil and synthetic.

[subbum]

I am no Mr. Mechanic, but I always heard that you shouldn't switch to synthetic oil after using regular motor oil in your engine. I can't remember the reasons why, but I remember someone lecturing me on the subject.

 

As far as the ticking......it seems to be an oil pressure issue but I have found that it may not be related to the oil pump/mickey mouse ear thing. I have a new oil pump and seals and my motor still ticks away when cold. Using 20W-50 solved it, but starting in the morning with that sludge was like churning butter. The Marvel Mystery Oil seems to work a bit, but I am cautious about using to many additives.

[jeffast]

the rule as i was told with synthetic was don't switch to it after a certain point like 100,000+miles and never never NEVER break an engine in on it

[operose]

the rule as i was told with synthetic was don't switch to it after a certain point like 100,000+miles

 

this "rule" as you call it, is a "myth" and has been hashed over MANY MANY times on the usmb.

 

http://www.bobistheoilguy.com

[mikeshoup]

the rule as i was told with synthetic was don't switch to it after a certain point like 100,000+miles and never never NEVER break an engine in on it

I've heard that before too. But, you usually just fill it up with dino oil, then after the next oil change, you're safe to switch to synthetic.

 

One of the reasons I've heard its not a good idea to switch to synthetic on high milage cars is because synthetics have stronger detergents, and you'll end up cleaning out all the gunk that's holding your seals together. You'll have oil leaks popping up everywhere.

 

You're also not supposed to mix synth and dino oil, so if you do switch, you want to run some sort of flushing product (usually just a strong detergent) through the engine and flush out all of the dino oil varnish and sludge.

[Subarian]

Most sythetics are completely compatible with petroleum oils.

[anthony walker]

aint no big thing homie, its jsut you gap in your comb chamer between rings. your computer is not adjusted information wise as to how to handle or your engine was not broke in with full syn. therefore it takes a few minutes for things to heat and expand to take care of the gap. remember always let warm up and cool down when using fully synth. rock on brother

[86subaru]

if you have oil leaks it will leak more ,

[Gl-boost]

whoa, had a long night of work yesterday and didn't get a chance to get on after.

 

I don't see why you can't mix synthetic with regular, they have synthetic blend oil thats not full syntec.

 

As for oil leaks I have had some before and have noticed them still, I amm still monitoring the oil level and watching it greatly.

 

So everythings ok then, I just was worried about that tick when cold but I let her warm up and cool down anyway, i don't like o boost on a cold engine and let her idel after driveing.

[bgd73]

10w30 synthetic maintains heavy weight longer than regular. For your exact prob in my car I chose 5w30 if using synthetic (castrol).

[4x4_Welder]

The only thing I have noticed with my car is that it burns WAY more oil running synthetic blend than straight dino oil. I mean, blue cloud until it warms up, constant oil smell, and burns better than a quart every 100 miles. Only burns about half that on regular oil.

Synthetic is ok in older engines, and if you take proper care of your engine you shouldn't worry. When I change my oil, I run Castrol GTX. I have taken apart engines of my own that were run on that exclusively, and the inside was bright and shiney after 30k, absolutely no buildup at all. Don't run Q-state or Penzoil, both will turn the inside of your engine orange with waxy residue.

[zyewdall]

Never noticed it on my subaru, but my truck does seem to knock more when cold on synthetic (It's a diesel too, so it always knocks to some extent, and I'm not sure how good a test this is, because I also switch between different diesel and biodiesel blends, and in general it knocks more on diesel, and quiets down alot on biodiesel). I can't think of any reason it would knock more on synthetic, unless it's not knocking, but cold piston slap that would normally be muffled by thick gooey dino oil when cold. Not sure if that makes any sense either...