I just purchased a WRX yesterday with 29K miles. I have no idea if the car has been switched to synthetic oil yet. My question is should I make the switch and is there any problems with making the switch after 29k miles, Thanks.

Scott

 

You will have no problem switching to Syth. at your milage. i recomend Mobil1.


-PJ

 

You will have no problems switching to Synthetic oil at this time, when your changing your motor oil, it would be a further benefit to change your tranny and rear diff along with the motor oil. I recommend Mobil1, however; if you want something to talk about, you can use Redline or Modul. After you make the change, your initial feelings will probably positive, but, give it a few days and your car will feel smoother and more powerful, because it will be.

 

Sundance,
How often should you change the lube in the tranny and diff.? also, what are the two other lubes that you were talking about?

 

just wanted to clarify something sundance said. use mobil 1 in your engine, NOT in your rear diff. or tranny. those both take 80/90 gear oil. those don't need to be changed as often as motor oil, but checking them on a regular basis is a good idea. redline is a high performance oil, also royale purple. they are crazy $$ though. stick w/ mobil1 unless racing, or have lots of cash to spend.


-PJ

 

Just to clarify my original post, synthetic motor oil can last through 6,000 miles between oil changes, however; it depends on how you drive and where. If you are constantly shifting at above 4000 rpms, I would and do change it every three thousand miles. Tranny and rear diff require GL-5 gear oil, which translates into 75w90 and is clearly printed on the container. I change tranny and rear diff every 1,500 miles. Just like in anything, there are differing opinions on which oil is best. Some say Redline, others Modul and yet others say Mobil1. The reason I use Mobil1 is that the company is huge and spends an enormous amount of money on R & D, it works real well and its easy to get.

 

There are differing opinions on synthetic oils. As soon as I find the research I will post the papers here ( if I can find the white papers again) as for synthetic gear oil, I run Mobil1 75-90 in the trans and diff. The trans and diff are a 30,000 mile change. If you drive real hard and mash the gears, 15,000 is acceptable, but not required.

As for Motor Oil, Opinions are like @$$holes, everyone has one. Here is mine. Synthetic oils take longer to break down, so they are exceptional for people who aren't timely on their oil changes. If you change oil every 3000 on the dime, then for all purposes in MY opinion its a waste of money. If you change oil every 4500 or so then invest the extra in the synthetic. However, synthetic carries contaminates just like any other oil. What I do know, comming from an air cooled VW past is that Synthetic oils hold heat and remain hotter longer than convetional oil. Gene Berg, a very well known VW performance engineer has lots of documentation on this matter, of course air cooled engines need every ounce of cooling they can get and synthetic is not a viable option. I prefer to use Kendall GT1 10-30 I pay about $2 a quart and change it every 3000 miles. Kendall has proved to work quite well and is one of the few good conventional oils out there. Kendall and a Purolator oil filter keep my oil pretty between changes. People can say what they want, but this combo got me 216,000 miles out of a VW engine without a rebuild, the average oil temp was 210 with 230 not uncommon in the hot California air. This engine was still running well when I sold the vehicle.

One more thing I'd like to add, the type of driving you do matters as well. Are you a stop and go around town guy? Lots of engine starting? The thinner Synthetic has an advantage, be it marginal it does. For long commutes then again I FEEL it's a waste of money. What I can say is stay away from Penzoil, Quaker State, and Castrol. I have torn apart many engines running these oils and after they get hot, they look like gelatinous goo.

As I say again this is MY opinion. Please read my disclaimer.
(standard disclaimer): "Any advice you take from me is YOUR RESPONSIBILITY. I have stupid ideas that will probably ruin your stuff, set your house on fire, bring the FCC to your door, ruin your crops, and send famine and pestilence across the land. And as the operator, it is YOUR RESPONSIBILITY to not take the word of some raving lunatic on the web with funny colored hair, and find things out for yourself. Your mileage will vary. I'm probably lying. You have been warned."

 

http://www.petronomics.com/syn_pet.htm . Look at this link it's titled:
SYNTHETIC
or
PETROLIUM-BASED LUBRICANTS?


One thing most people do not take into consideration is where is the article coming from and who is benefitting from its statements. For this reason, Avoid any information written by Redline, Mobil, Amsoil, or any other Company with a stake in their statements. The article above is not for automotive use, but still factors the same reasoning on some keynotes. Other are entirely different.

If you have or know of someone who has a subscription to Lubricants World, they are the source I found my initial white papers at. Unfortunately my neighbor who was an engineer passed and I no longer have access to this info. I swear I'll find it though.

This link here http://www.1st-in-synthetics.com/newsletter_1000.htm is very biased as they should be, they sell synthetic oil. Read what they have to say about the "right" to call an oil synthetic. Interesting.