Jump to content
Ultimate Subaru Message Board

Synthetic, does it really make a difference?


Recommended Posts

Is it just a rip-off or does it really make a difference in term of performance, fuel economy (saves gas) and all the claims they put out there? Need help as I'm going to waste another $50.00 to get about 10 qts. of Synthetic ATF Fluid for my tranny. Want to know I'm not just wasting money for nothing...

 

Thanks in advance...

Link to comment
Share on other sites

Well, the really nice thing is that it's more durable than dino oil, as in it doesn't really break down. You can go much longer between changes. I just switched to that Mobil 7500 mile semi-syn, and while I haven't noticed a performance difference, it was less than twice as much, and I'll be using it for twice as long.

 

These people are doing a study on synthetic oil.

Link to comment
Share on other sites

Studies, like the one done by Consumers Reports, have shown NO benefit to using synthetic engine oil over regular dino. Regular oil and filter changes, using any type of oil, are the most effective way to extend the life of your engine.

So, I do not use sythentic motor oil. BUT I do use synthetic ATF. Why? ATF gets MUCH hotter than engine oil. The superior thermal stability of synthetic oil actually has a benefit in the much hotter enviornment of the AT. Most people have seen burnt dino ATF, it turns brown and smells "burnt". But an engine will sieze way before it gets hot enough to burn even dino engine oil.

Also, I change my engine oil every 5,000 miles, but the ATF only every 30,000.

So so more expensive synthetic is much more cost effective in the AT. I've got money to spend, but not to burn.

Link to comment
Share on other sites

Thing is, did they do the research on a turbo charged engine? Probably just some V-6 with no real performance. The thing is it wont break down like dino oil does. If you change your oil ritualistically at 3000k then don't use syntheic. Also, I dont know if you know this but all the new turbo subs out there say nothing less then full synthetic, why? Inside the turbo the temp is extreme! With regular oil, when it runs inside the turbo to lub it up you have a good chance of coking the oil. <-- This is when it breaks down and sludges up. Take some coke or pepsi and pour it on to a got burner and it will carmalize = coking. With synthetic it has an extreamly higher coking threshold, allowing the turbo to run better and keeping that crap out of the engine or cloging your oil lines.

 

Also

 

Along with this you can run synthetic for a far long period in your engine due to less degredation.

 

Ask the WRC, F1 or the forbidden (forgive me for these words coming out of my mouth)Nascar:dead: what they run in their engines, they will tell you FULL SYNTHETIC!!!

Link to comment
Share on other sites

I would agree that there may be some benefit to using synthetic motor oil in a turbo engine. But the original poster was asking about synthetic ATF.

Anyway, I've owned a car with a turbo, and I know that one of the biggest problems is having the oil carbonize in the turbo bearing. That's why you have to "simmer" a turbo engine after a hard run. You want the engine, and especially the turbo unit, to have a chance to cool down.

So here's my question. If you shut down a hot turbo engine, without "simmering", is the sythetic oil tough enough so the oil WON'T carbonize in the turbo bearing?

Link to comment
Share on other sites

Is it just a rip-off or does it really make a difference in term of performance, fuel economy (saves gas) and all the claims they put out there? Need help as I'm going to waste another $50.00 to get about 10 qts. of Synthetic ATF Fluid for my tranny. Want to know I'm not just wasting money for nothing...

 

Thanks in advance...

 

I think the universial conclusion is that synthetic does have proven viscosity stability - this translate to less wear on cold engine startups and reduced breakdown during high temperture performance. Still, I have not seen conclusive studies that compare results of long term (say > 200K miles) uses between synthetic and conventional oils. In either case, regular oil/filter changes are the best protection. If you got the cash and it gives you a warm and fuzzy about engine maintenance - go synthetic

 

BTW, I personally have not seen any fuel economy gains on my 2005 XT after switching from conventional to Mobil-1 synthetic, but use it due to the temperture extremes here in MN (thats my warm(and cold) fuzzy weather reasoning for using it).

Link to comment
Share on other sites

I started converting to synthetic in 1981; engine oil, gear lube, even grease. It is worth the extra cost, especially if you stretch the service intervals. I would not go 7,500 miles on oil if I was using dino juice, but I have gone about 15k on Mobil 1 on all of my vehicles (outside of warantee) since 1981 and always go over 150k on my vehicles. Most recent high mileage car was a 1988 Saab 9000 with 250K miles. Totalled out, but using essentially no oil. Mobil 1 annual changes since 1k miles in 1989.

 

My 01 Legacy GT is getting it's last 7,500 mile change this weekend at 53k to meet the warantee requirements. After this, it's annual changes each spring.

 

Jack

Link to comment
Share on other sites

Thanks for all the replies, guys. I have concluded that I will get the Synthetic ATF for my tranny and change the screen/filter as a complete maintenance. Afterall, this is a new used tranny that I just put in, so I want to take good care of it from the start and see how long it would last. The last one I put on lasted only 4 years (7/01-7/05). Wow, that's a coincident, same month! Wouldn't you say so?

Link to comment
Share on other sites

...So here's my question. If you shut down a hot turbo engine, without "simmering", is the sythetic oil tough enough so the oil WON'T carbonize in the turbo bearing?

 

From what I am aware of there is no carbon in Full synthetic, preventing carbon buildup. I pulled this from the AMSOIL website. check it out!

 

Petroleum motor oil only has a film strength of about 400 psi where AMSOIL has a film strength of 3300 psi and does not break down, shear or loose viscosity under heat and stress. Petroleum motor oil breaks down under heat and stress and leaves carbon, varnish and sludge deposits in your engine and allows your critical engine components to wear much more rapidly. It's no wonder you have to change it every 3000 miles and your local quick lube or auto dealer can't wait to see you again to charge you more of your hard earned money!

 

The link...

http://members.cox.net/synthetic-motor-oil/

Link to comment
Share on other sites

From what I am aware of there is no carbon in Full synthetic, preventing carbon buildup. I pulled this from the AMSOIL website. check it out!

 

 

Thanks for your reply. However there is plenty of carbon in BOTH synthetic and dino motor oils. That's why they are called "hydrocarbon" compounds.

I'm surprised that you don't know about simmering a turbo since you own one.

The turbo uses a fan driven by exhaust gases to compress the air/fuel mixture on the intake side. As a result, the turo gets extremely hot. The oil running through the turbo bearing actually helps keep the bearing cool. If you shut the engine off without allowing it to cool, the stagnant oil trapped in the turbo unit will overheat and actually burn!!!!! The oil burns leaving a residue of hard carbon. This blocks the oil passage of the turo unit, and pal, you need a one!!!

A hydrocaron (HC) like oil or gasoline burns, combining with the oxygen (O2) in the atmosphere, and you end up with water (H2O) and carbon ©. You can see water vapor coming out of your tail pipe, and the tail pipe usually is covered with a black carbon soot. Know you know why.

Link to comment
Share on other sites

Thanks... I did know that but thank you for the info. This is the purpose of a turbo timer to HELP prevent the coking from happening. As does TRUE synthetic oil also. Coking starts at 300degF. AMSOIL claims their oil has extreamly protective at 306degF.

 

Got this from MOBILOIL.com.\/

Historically, conventional oils lack the performance of synthetic oils in the areas of low-temperature performance and high-temperature oxidation stability. Conventional motor oil is made up of an inconsistent mixture of long and short chains of carbon and hydrogen atoms. In the extreme heat of an engine, short-chain molecules can evaporate, and unstable molecules can oxidize and break down. Conventional oils also contain much greater amounts of impurities, such as sulfur, reactive and unstable hydrocarbons, and other undesirable contaminants that cannot be completely removed by conventional refining of crude oil.

 

Mobil 1 uses high-performance fluids, including polyalphaolefins (PAOs), along with a proprietary system of additives. Each Mobil 1 and Mobil 1 Extended Performance viscosity grade use a unique combination of synthetic fluids and selected additives in order to tailor the viscosity grade to its specific application.

Here is AMSOIL's recommended change cycle for their oil. INSANE!!!!

Service Life

In personal cars and light-duty trucks with non-turbocharged gasoline engines: Drain oil at 25,000 miles or one-year intervals, whichever comes first.

 

In turbocharged gasoline engines: Change oil at three times the engine manufacturer's recommended drain interval or six months, whichever comes first.

 

In high performance and racing engines: Change oil at intervals specified by used oil analysis.

 

 

http://www.harley-performance.com/amsoil-amo.html

 

 

My big argument is --- I will never put anything less then FULL SYNTHETIC in my turbocharged car.

Link to comment
Share on other sites

Well, went and bought 2 qts of Gear Oil and 10 qts of ATF for my tranny. Was gonna change it tonight but too tired after work. Dang, the ATF is expensive, $71.99 for the 10 qts bottle. The individual quart bottle is even more expensive ($7.99/qt). So, I saved $8.00 by buying the 10 qts bottle. I hope it'll make a difference as I spent $72.00 (AMSOIL Synthetic) vs. roughly $20.00 for conventional fluid.

Link to comment
Share on other sites

Thats awsome! Let me know how that stuff works!! I may be getting some for my cars. Expensive though. I guess if it lasts 3x longer then conventional and lower operating temp it would be worth it. Save your transmission some years.!

 

AMSOIL Synthetic ATF resists high temperature degradation three times longer than conventional ATFs do. It has been reported to reduce high operating temperatures up to 50° F. In fact, heat is such a non-issue for AMSOIL Synthetic ATF, it may be used as a fill-for-life fluid. It needs no replacement in normal operating conditions.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...