Synthetic engine oil

who's using it pros/cons of using synthetic oil.

Practically everyone is using synthetic. It is far superior to dyno oil in its lubricating abilities and does not break down over time like dyno oil. Only cons are that it is more expensive but for longer engine life it is very worth it. If you want to know which one to use, don't ask because you will get many different answers. Mobil 1, Amsoil, Royal Purple, Pennzoil, Quaker State and a host of others are excellent. Probably the number one on this board is Mobil 1.

Not good for high mileage vehicles that have been running dyno though, am i correct?

I'm at 309,000 miles all on conventional 10W30 Havoline. For my application I do not need synthetic.

Not good for high mileage vehicles that have been running dyno though, am i correct?

I would not convert to synthetic if you have a high mileage vehicle. Plus all of the engine gaskets and seals (valve cover, oil pan, rear main seal, etc) must be in good condition and not leaking.

IMO whether you use dino or synthetic is a matter of personal preference.

I feel synthetics are a waste of money. I have always used conventional oil and have never had an oil related failure in any vehicle I've owned. Most had well over 200k on the odometer when I got rid of them and were running good. The only thing I would consider running a synthetic in is a highly modded or high rpm application that gets hammered on every day. Many people swear by synthetics, and that is their personal choice. I'm not saying they are wrong, this is just my opinion based on my real world experience. Be careful too, because some synthetics are just dyno oil with molecular modifications. Since these molecules do not exist in nature, they can legally call them synthetic.

I feel synthetics are a waste of money. I have always used conventional oil and have never had an oil related failure in any vehicle I've owned. Most had well over 200k on the odometer when I got rid of them and were running good. The only thing I would consider running a synthetic in is a highly modded or high rpm application that gets hammered on every day. Many people swear by synthetics, and that is their personal choice. I'm not saying they are wrong, this is just my opinion based on my real world experience. Be careful too, because some synthetics are just dyno oil with molecular modifications. Since these molecules do not exist in nature, they can legally call them synthetic.
Agreed in basis, I live where it reaches -25 in the winter, the cranking rpms are distinctively different( faster) with Mobil 1 than dino under these conditions. On the other side of the coin I have also gone 200k on my last 3 cars with dino use year round, but recently on my 2 late model Gm cars/trucks ,I use Mobil 1 in the winter.

You do not put in synthetic oil in the newer engines or the lifters will rattle like crazy.Put in what is recomended,it will say on the oil cap or in the owner's manual.My neighbor's wife went through this,she was talked into putting synthetic in her 1998 or 1999 S10 and she did.The lifters rattled like crazy and the engine sounding like to blow up.She did drain the synthtic out and put in what is recomended,the lifters quieted right up.This is a true story by the way.

^^^Interesting story and no one doubts the veracity of it. But I don't know about that. I've been using Mobil 1 in my GTP for over 8 years since new. No problems. No lifter noises. The same in my Regal GS for 5 years since new. No problems.

However, I still run dino oil in my wife's Regal LS and my Alero GL2. I would think twice about using synthetic oil in a GM 3.4L but the 3800s take well to it.

A lot of GM dealerships recommend using synthetic oil and it will not void any warranty.

I have to agree with Bob on this one. Synthetic is no different in viscosity than dino oil. It lubricates better and will often quiet noisy internal parts such as lifters since the cleaning abilities remove any type of deposits inside the working parts of the lifters. If the lifters in that particular vehicle made that kind of racket then there had to be something else going on.

What would be considered the high mileage point?

What would be considered the high mileage point?

I believe oil industry standards indicate 75,000 miles and above. But I know people that made the switch with mileage above this figure so it is really hard to say. Probably more subjective than objective.

Companies like Mobil have new synthetic blend oil to cover cars with high mileage and recommends using the blend stuff. Mobil Drive Clean Plus is one such product.

Special consideration must be give to engines with higher mileage because your internal parts are worn and the seals are older versus cars with lower mileage.

I see (and agree with) your point on the cold weather start-up issue Max, as synthetics do flow thinner at extremely cold temps. And of course Bob, your GTP qualifies for the highly modified catagory. I also agree with the switching older engines to synthetic. Some have done it with no problems, but most develop leaks if the seals/gaskets are worn.

I see (and agree with) your point on the cold weather start-up issue Max, as synthetics do flow thinner at extremely cold temps. And of course Bob, your GTP qualifies for the highly modified catagory. I also agree with the switching older engines to synthetic. Some have done it with no problems, but most develop leaks if the seals/gaskets are worn.

You don't have to run synthetic to get leaks, you'll get that with dino oil sooner or later, specifically valve cover, oil pan and/or rear main seal.

Maybe Troy should just flip a coin. :lol:

or go eeny meeny miny Mobil!!!

Most people who develop leaks after switching to synthetic say they clear up after a few oil changes... supposedly has to do with the detergents in the synthetic cleaning away the crud that's plugging the hole, thus casing the leak, but then the gaskets re-swell with the new oil supply.

I switched to synthetic at 200,000km with a known oil leak, and so far it's been great for me.

Mine coin has already flipped! Bought some M1 yesterday 5qts for 22 + tax at wallyworld. Most of my gaskets have been replaced...valve covers, lower intake, UIM < not that is matters. My oil pan is already leaking so who cares :evillol: so its just the front seal and rear main. Going to give it a whirl on my next OC. hopefully my 3800 likes 5W30 and I don’t make a sight hole in my block :eek:. I figured on my short communt to work syn like Bob said would probably be better plus maybe I'll eek out 1 or 2 MPG :dunno:


Troy