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Worth It??? Syntec vs Castrol 10W30


remoblades
07-09-2004, 10:37 AM
I have a '97 GC TSi V8. During my last oil change, I was told that my engine needs to be flushed due to the color and thickness of the oil. Is it worth it to use Syntec Blend as opposed to Regular oil for the next oil change? Will I see and feel results? I love this truck and I want to take care of my baby.Help.

JDPascal
07-09-2004, 01:59 PM
hi remoblades

Perodic flushing of the engine is worthwile. If you are changing the oil every 3000 miles like you should, a flush once a year should be lots.

Syntec is a good oil though not as good a value for the money as Mobile 1. They are close to the same price but different in composition as the mobile 1 oil is a full synthetic and the Syntec is a hydrotreated oil that is allowed to be advertized as a synthetic (as I understand it)

I am using the Mobil 1 10/30 in my JGC 5.2 and my Cougar 3.8 it works very well.

JD

YtseJam454
07-09-2004, 08:45 PM
If you change your oil every 3k I don't see why you would need to flush it. Flushing it only wastes oil. And Although Synthetics are far superior think of it like this. You have 2 buckets of oil. 1 has synthetic 1 has conventional. Now along comes a thunderstorm and fills the buckets with water and leaves and dirt. Is the synthetic better still even though it's contaminated? Are the contaminents not there anymore because it's synthetic? Are byproducts of combiustion not going to make it into the crankase b/c of synthetic? Why waste your money on synthetic unless you've got $$ to burn. You still need to dump it every 3k to get rid of those contaminents. The oil itself isn't what breaksdown very easily, it's all that crap that makes it inot the crankase. :2cents:

JDPascal
07-10-2004, 12:20 AM
If you change your oil every 3k I don't see why you would need to flush it. Flushing it only wastes oil. And Although Synthetics are far superior think of it like this. You have 2 buckets of oil. 1 has synthetic 1 has conventional. Now along comes a thunderstorm and fills the buckets with water and leaves and dirt. Is the synthetic better still even though it's contaminated? Are the contaminents not there anymore because it's synthetic? Are byproducts of combiustion not going to make it into the crankase b/c of synthetic? Why waste your money on synthetic unless you've got $$ to burn. You still need to dump it every 3k to get rid of those contaminents. The oil itself isn't what breaksdown very easily, it's all that crap that makes it inot the crankase. :2cents:


While I can agree with you on almost all points you have made, I still believe that the composition of synthetic oil is superior and gives better protection to an engine.

I'm not sure how using a flush wastes oil. The flushing additive is used with existing oil just before the old oil is drained out.

Especially on startup it has better flow characteristics and reaches the bearings far faster than conventional oils.

synthetic oils also have better heat resistance and less oxidation/thickening due to heat and usually the additive package is stronger in synthetics.

All things being equal a synthetic will give better service, especially when used from new in an engine.


But you are right about wasting your money if you are going to leave your engine open like a bucket and let unnecessary contamination into it through unserviced aircleaners, dirty fuel and other openings that should be sealed up and serviced.

The additives are there to deal with the normal combustion byproducts and the oil does need to be changed though extended drain intervals are possible. Extended drains should be monitored by oil analysis if pushed beyond about 5000 miles.

I guess the ones who would be wasting their money on the best oil are the ones using throwaway engines.

The cost/benefit of synthetic oil versus dino oil is something everyone has to decide for themselves. :2cents: :2cents:

by the way - how do you know the oil additives are used up and the contamination levels are max'd out at 3k - do you drive a chev?? :rolleyes: :rofl:

YtseJam454
07-10-2004, 06:12 AM
In my opinion flushing can do more harm then good. If you flush you may loosen sludge or carbon and where does it end up? In the oil pump pick up screen. I've replaced many of engines because of people doing this. When I remove the oil pan I find the screen packed and restircted and the explanation for oil starvation.

No one knows just how contaminated their oil is @ 3k but it's accepted as a known good value for general dumpings. I find with all of my vehicles except for my Nissan, the oil just looks and smells like it needs to go. My Nissan looks like I just changed it every 3k but I do it anyway.

remoblades
07-10-2004, 02:54 PM
Thank you both for the information. However I'm still somewhat undecided. You bth have very valid points and provided tons of info. I believe that a flush once a year can only help not hurt. And what I've been told is that syntec resists heat at a much higher level than dino oil. I've just been informed that Syntec Blend is also on the market.How does that compare?

I ask these questions because I absolutely fullheartedly LOVE my 5.2L V8. I was told by my mechanic that the engine shud be flushed because adding clean oil to a filthy engine makes no sense: The oil will get contaminated with sludge in no time. I assume thats correct..No one takes a shower and hops in a dirty bed, right?

YtseJam454
07-10-2004, 08:29 PM
Well lotsa people do :grinno: The Flush your oil thing is the latest in upsells. Sludge should not form unless you do not change your oil or already have a problem. There are much better ways to spend your $$ to keep that engine from dying too early. Mine has 231,000 original miles and doesn't use a drop of oil and if you pulled my rocker cover off you'd think the engine had 10,000 miles on it. I've never used Synthetic in my Jeep either.

bobby95
07-12-2004, 10:19 AM
If you hang around car guys much you know that this topic is debated almost as much as the "Regular Unleaded vs Premium" issue. I don't know if there is a black and white answer to your question. It has more to do with what your looking for than anything else. Both of these guys had excellent answers. While I think no one will argue that synthetic oil is superior to dino oil, if oil changes are done regularly I don't think your engine is going to run any cleaner or better with synthetic than it will with dino oil. I mean people have been getting outstanding service out of their vehicles for many, many years before synthetic came along. But I will tell you why I recently switched to Mobil 1. Suppose your $3.00 thermostat goes bad and sticks closed and your temp sensor is also bad (just happened to me). Before you realize you have a problem your engine is so hot your oil pressure has dropped considerably and your motor is knocking like you know what. If I would have had synthetic oil in it it would have tolerated the high temps much better. So you could think of it as insurance. Anyway, that's my two cents worth. Good luck.

remoblades
07-12-2004, 10:31 AM
Insurance is good enough for me. I'll take it. What's with this Mobile 1? Is it a synthtic oil and is it the best? Many people use it.

How do you feel about an engine flush once a yr Bobby?

In terms or Premium vs Regular Unleaded, I use Regular cause thats what I can afford. I'm assuming Regular doesn't hurt a '97 GC. Is gas grade that serious? Premium is almost a pack of cigs!!

bobby95
07-12-2004, 03:52 PM
Yeah, Mobil 1 is synthetic and I've just started using it so I can't give you a personal opinion but at least with the guys I know it has a good reputation. I used Castrol before (dino oil) but was really disappointed when it broke down so soon when my JGC ran hot. As for engine flush, I've never done it but I will say that both the arguments above are very convincing, but its just something I've never done. As far as Regular vs Premium, in my opinion Premium is a waste of money because modern engines advance the timing when needed anyway, eliminating the need for higher octane fuel. This is not only my opinion but also Road & Track, Motor Trend, etc. But I wouldn't be surprised if someone didn't post right away that I'm an idiot for using Regular. It's just one of those things that's not going to hurt you either way. Good luck.

YtseJam454
07-12-2004, 04:40 PM
You're not an idiot. In fact Regular combusts more readily at lower temperatures and that's about it. The only good reason for running premium grade fuels is to resist detonation caused by higher compression ratios. Compression ignition engines (Diesels) only compress air and then a fine mist of high pressure oil is sprayed into the combustion chamber where it ignites due to the high temperatures of the air being compressed. 70°F air can reach temps of over 1000°'s F by compressing it. If you compressed air mixed with fuel that didn't resist ignition at lower temps it would self ignite as the air fuel mixture is compressed. The result would be an explosion in the combustion chamber followed by another flame front created when the spark plug fires. Detonation will destroy an engine by literally tearing it apart internally. Companies want you to believe higher octane fuels are cleaner, better, and will give your car more power but that's just false.

As far as the computer being able to compensate for it that's not entirely true either. The advance curve and base ignition timing is set by a base setting if it uses a distributor manually. On a DIS system The PCM will not retard the timing until spark knock is detected through the Knock Sensor. At that point it's engine performance that is suffering because something is wrong. Spark knock is not a normal condition nor is retarding the timing for the sake of using cheap gas. If the engine was designed to run on premium fuels then they should still be used. Sorry for the long post.

broncoguy75048
07-12-2004, 06:24 PM
There is a lot of interesting (and technical) oil and lubricants info on bobistheoilguy.com. I have spent many an hour on there, and still don't know as much about oil as they seem to.

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