What Synthetic Oil Do You Use?

I use two different oils regularly: Valvoline semi-synthetic, Mobil 1 synthetic. They both seem to work well.

dang im the only one using Valvoline MAX LIFE sythetic blend! ah pretty good oil, better than my old Mobil 1!!!

Mobil 1

Mobil 1 for all 4 cars in my household

I use Castrol and so far I am not disappointed.

Blog Carburado

ROYAL PURPLE!!! I fell in love with Royal Purple about 3 years ago. I first used it in my 1996 Chevy Blazer with about 125,000 miles on it. After I switched from conventional to synthetic, I gained an honest 1 mpg around town and 2 mpg on the freeway. I also love I only have to change it every 7500 miles. I just bought a mazdaspeed 3, so I’m either staying with Royal Purple or I might go with Redline since I’ve heard they design their oil for turboed cars. Anyways, go with Royal Purple, you won’t be let down.

Sorry in advance for the length….

Having been in the automotive service business over 40 years it’s save to say I have seen many good and bad reasons for various oils. It can be like arguing who’s the best politician or make of car but it’s very important to understand some very important but basics when discussing motor oils.

First of all, for most engines, synthetics are the best. (Not always) And indeed oil life can last considerably longer than conventional oils BUT keep in mind that during normal engine operation there are reasons why your oil is getting dirty and why it needs to be changed. As an engine cycles from hot to cold condensation forms just like it does in a bathroom window and ends up in the oil. And keep in mind if some oil did not get up to the top rings they would burn up, thus some oil has to burn in any engine. Anyone saying, “My engine don’t burn a drop of oil.” doesn’t have a clue what their talking about. For the same reason that oil has to get by the rings, fuel can just as easily get past and into the oil. Then there are alkaline’s that build up and other chemical issues that happen. It’s these build ups that replace the oil burnt while lubricating the upper rings that makes the oil level stay the same. Equally important is that these alkaline’s and carbon deposits become microscopic “grit” not at all unlike sand and as hard as metal filings. You don’t have to be a rocket scientist to realize what that is doing to bearings and machined surfaces within the engine. Another very important thing that oil needs to do is to “Suspend” contaminants that are in the oil. Many oils do not suspend all sediments, carbons, moisture and so they tend to lay on the bottom of your engine in the form of sludge even when you drain the oil. Mobil One is one of the best at suspending all of the above thus removing it all during a drain and refill. If you have ever seen engines torn apart this will become very evident. Paraffin base oils like non-synthetic Penzoil for example are really bad for this unless used in very cold climates like back east in the winter.

The bottom line is… While synthetic oils do in fact not break down or wear oil, there is still a need to change it so that the bad stuff suspended within the oil is removed. The more often you change your oil the longer the engine will last. If you follow recommended intervals on your average run of the mill car, there is no problem at all even with longer than normal intervals. On the other hand, if you are talking about race engines that is NOT the case.

For example, during a typical race season when we are racing/testing a full weekend at least once or twice a month for the entire year, most teams engines will run strong for about 65 hours which is usually just short of a full season thus requiring them to rebuild or at least have two engines for the season. But when I ran my motors (and I run them hard) using Mobil One and changing it after every weekend of racing, my engines lasted well over 150 hours. The fact is over 10 years this was the case and nobody could say my engines lasted longer because I didn’t push as hard especially considering we won the seasons championships every year that I ran. Like my grandmother used to say… The proof is in the pudding.

I used to do my own oil changes till some used motor oil spilled in the back of a newly-restored cherokee. Now I go to WalMart and have them replace the oil and use Mobil 1.
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My experience there is that they have more conscientious and skilled workers than Jiffy Screwed, and I can choose exactly what I want put into my car without hassle and without the counter guy trying to push unwanted products or procedures on me – and the OC costs a lot less than the other place, even with Mobil 1.

I use Mobile 1 when I do it myself. Costco sells cases for about $5.50/bottle, which is great if you need 10W30 or 5W30. The place I’ve been taking it to locally uses a 76 full synthetic, if I recall correctly. I don’t favor it, but I get my oil changed every 3,000 miles and with a coupon, a change there is only $19!

I use Amsoil mainly because its rated for more miles than mobil 1, even though i know mobil can go for more than 5000 easily. Plus it costs more and i got a bunch free from work this summer, so i figured what the hell. Its hard to find it at the local Napas and Autozones though.

I’ve been using Mobil 1 since I started driving, and my dad was using mobile 1 long before that. It’s never done us wrong, so why mess with a good thing?

Plus, I’m cheap and lazy, so in my daily driver, I’ll go 10k on a change with no issues at all.

I use Castrol 10-60 for my E39 M5. That seems to be the leading choice on the M5 forums.

I use Mobil 1 or Mobil 1 High Mileage only, period. Also, I never exceed 4000 miles between changes.