Regular vs. Synthetic

Juniorverse · #1 (**permalink**) 03-26-08, 01:31 AM

O.K., so my barely moved (2 K in the last 10 months) '03 CTS (39,000 k) is starting to get a little long in the tooth and I was wondering when I should make the jump to synthetic oil. I think I read somewhere that higher mileage engines run better/last longer with synthetic oil. I just don't want to start $60.00 oil changes too soon. Or should I just stick with regular oil altogether?

Discuss....

Thanks!

ABCF · #2 (**permalink**) 03-26-08, 01:52 AM

with new vehicles i start using it at about 6000 miles or at my second oil change. imo 39k is not high mileage your car is just nicely broken in.

C&C · #3 (**permalink**) 03-26-08, 06:21 AM

You don't really need to switch to synthetic; it's your choice. I would consider switching if you live in extreme conditions. Synthetics do your engine good when it regularly has to deal with extreme cold or heat. If your engine isn't stressed by these type conditions regularly, regular dino oil will do just fine.

As for switching after break-in, that's not really a requirement; quite a few engines come factory filled with synthetic. (Synthetic isn't any more slippery than conventional oil, it just resists viscosity break down better.)

kramcard6 · #4 (**permalink**) 03-26-08, 08:23 AM

I run Synthetic in my Corvette but not in the CTS! It's a waste of money in the CTS, Like C&C said, unless your drving the PISS out of your CTS it's not worth it!

iwa100 · #5 (**permalink**) 03-26-08, 12:31 PM

As soon as I bought the car I switched over to sythetic. I can really notice the difference in the way the car drives though between regular and sythetic. Regular makes it seem sluggish as opposed to conventional oil.

Chief_AT · #6 (**permalink**) 03-27-08, 09:52 AM

When I had a VW station wagon - years ago - I drained the fossil oil and filled with Mobil 1. About ten seconds after started the engine, I had to run to the engine and lower the idle speed setting - the engine was revving over 1k rpm. When I sold the VW, I replaced the Mobil 1 with fossil oil, and had to raise the idle speed setting so that the engine would run. That Mobil 1 definitely had an immediate effect on engine speed, and it had to be related to reduced friction.

C&C · #7 (**permalink**) 03-27-08, 12:23 PM

Quote:

Originally Posted by iwa100

As soon as I bought the car I switched over to sythetic. I can really notice the difference in the way the car drives though between regular and sythetic. Regular makes it seem sluggish as opposed to conventional oil.

Quote:

Originally Posted by Chief_AT

When I had a VW station wagon - years ago - I drained the fossil oil and filled with Mobil 1. About ten seconds after started the engine, I had to run to the engine and lower the idle speed setting - the engine was revving over 1k rpm. When I sold the VW, I replaced the Mobil 1 with fossil oil, and had to raise the idle speed setting so that the engine would run. That Mobil 1 definitely had an immediate effect on engine speed, and it had to be related to reduced friction.

Unless you changed the viscosity of the oil (substantially), when switching, I'm calling B.S. on both these posts. Synthetic is no more slippery than conventional.

nickc50310 · #8 (**permalink**) 03-27-08, 12:42 PM

I hope youre not running convential in your STS.

tommy compton · #9 (**permalink**) 03-27-08, 12:56 PM

sythetic always, it's just better.

philly88 · #10 (**permalink**) 03-27-08, 01:36 PM

I use regular in my SUV and change it often. I only use the synthetic in the CTS, which is recommended by the way in the manual. I'm in northern ontario, plenty cold up here and when its -30 its good to have that oil flowing as quick as possible.
That being said, I change the oil in my SUV EVERY 3,000 km no matter what the carputer says. In the CTS I'm waiting until I get to 20% engine oil life which I'm almost there and I get about 5,000km out of it before changing.