Differences in synthetic oil quality?

There are differences in oils, synthetic or not. Generally an API rated SM oil will be fine, although some very good good oils are not API rated. However, I feel uncomfortable going to some off brands as I worry about there continuing quality control. ExxonMobil has in Mobil 1 a very fine oil that has proven consistent performance over many years.

Rumple

 

Without getting your feathers ruffled, may I ask, can you point to any independent evidence that Mobil1 is a better product than other motor oils?

Or is it only its consistency that impresses you? That is not a small thing, but even if that is a good reason to stay with Mobil 1: what evidence is there that other motor oils are not consistent in their quality?

There is lots of evidence that consumers believe when something is expensive it is of high quality. I think Mobil1 benefits from being one of the highest price synthetic oils available to consumers, and the fact that Mobil1 is well known only helps ExxonMobil sell it.

Is there an independent source (SAE chemists, anyone?) that compares currently available synthetic oils, for use in the Prius?

 

He didnt actually say that mobil1 was better than other synthetics.

I dont usually use full synthetic oils unless they are on sale (like the pennzoil platinum $15 rebate offer) and Im upto 212,000 miles. I think changing the oil regularly is more important than the brand you use.

BTW i normally use the semisynthetic valvoline at walmart for $12/5 quarts.

 

It has been proven time and time again that Synthetics are much better then Conventional oil. As far as between brands I agree you are going to be paying for some of the brand and advertising schemes, but the largest differences are going to be in the additive and cleaning formulations inside. I have learned that the European standards are a better indicator on the quality of oil you are buying. For this reason I look for the ACEA rating
ACEA categories

A / B – Petrol and diesel engine oils.
(A =petrol engines and B =light duty diesel engines)

A1 / B1
Oils intended for use in petrol and diesel car and light commercial vehicles specifically capable of using low friction, low viscosity oils with high temperature / high shear characteristics.

A3 / B3
For use in high performance petrol and diesel cars and light commercials where extended drain intervals are specified by the vehicle manufacturer and / or for year-round use of low viscosity oils and / or for use in severe operating conditions as defined by the vehicle manufacturer.

A3 / B4
For use in high performance petrol and direct injection diesel engines. Also suitable for applications described under B3.

A5 / B5
For use at extended oil change intervals in high performance car and light commercial petrol and diesel engines designed for low viscosity oils.

 

As Morpheusx says, go by performance spec and not label. A couple years ago I copied advice from a G2 Prius driving engineer (author unfortunately since lost, but thanks!) that I have followed since. 90% of the time I buy Pennzoil Platinum synthetic, since it tends to go on sale, but Germany sourced Castrol syntec is an excellent choice too. When the post quoted below was written, mobil1 had been cheapened down to a lesser quality than competitors, but I think it has since become a tier I oil again. I don't buy it because it is poor value (expensive for equal quality), and I tend to hold grudges against manufacturers who play marketing games like Mobil did by trying to sell a cheapened product once brand name recognition was gained. fwiw, I change oil and filter every six months, which is about 7 - 10k miles. Car is close to 100k miles now with no oil loss between changes. I *should* have my oil checked, but so many other people have shown that the interval is fine that I have been lazy. I'll get around to it ...

 

I've been using Mobil 1 "Extended Performance" 5w30 - it costs a few dollars more then the regular Mobil 1 but meets the higher requirements. And with recent rebates and sales have consistently been a good deal in my area.

 

Mobil 1 specs on their website are contradictory. This page says GF4 and A1, but does not mention A5. The product page says GF4, A1, and A5. Mobil 1 EP says all three.

Who knows ? I think the EP formulation meets our requirement for A1,A5, and GF4, but am unsure about the previous M1 stuff. I usually end up paying about 2$/qt for the Pennzoil A1/A5/GF4 synthetic, although my last purchase was 1$/qt.

Addendum: I just looked at the bottle of my Pennzoil platinum, which says A5/GF4 but not A1 ! Makes me think Pennzoil has pulled a Mobil, and downgraded the spec. I'll have to check further.

 

More info than you ever thought you wanted about oil here: Welcome

 

I just came back from that site. I find a bunch of opinions, but have yet to read something akin to a sticky that summarizes best practices.

Help ?

 

I fail to see what is wrong with the ACEA A3/B3,B4 oils. Too thick for the Prius? I even ran Esso XD-3 15W-40 one summer in my Prius, the only downside was I perhaps lost 2 mpg, but that could have been due to the very windy summer we had

In summer, running Mobil 1 0W-20, Mobil 1 0W-20, or Castrol Syntec 0W-30 (The made in Germany version), no difference in fuel economy. All had good used oil analysis reports

 

I'm always amazed when I read these oil threads about how little people say they pay for synthetic oil. In my area, I have trouble finding regular Mobil1 for less than $7.00 per quart. 0w20 or 5w20 is usually more and you can almost never find it. I've looked at Strauss, Pep boys, Auto Zone, Kmart...

 

I get my oil two ways first I go the website for both Autozone and Advance Autoparts (the two major parts chains in my area) you can view their Store circular flyers online and they both usually have both a conventional oil deal 5 quarts + filter usually about $14 and then buried on the last page they usually they have a synthetic oil deal with 5 quarts + filter for $29. From there I decide which of the synthetic deals comes with a quality filter usually one of them will be a Mobil 1 or K&N, but sometimes its crap like Fram or Bosch. Other times I just go to Wal-mart and buy the 5 quart jug of M-1 EP for about $25 and then go a good filter at the parts store.

 

I got a 5qt jug of pennzoil plainum 5-30 for $20, then noticed a $15 rebate is going on. For a different car, but that's cheap.

Bosch filters are excellent, since they bought Purolator. It's essentially a Pureone now. I would use them exclusively, except I have a stash of Japan and Thai made Densos. I bought an M1 filter at WM, it looks identical to the $3 Supertech except for red anti drain valve, so took it back. Even the box claims are the same. They are both made by Champion, like Bosch was previously. For the Prius application, the Bosch looks like a great filter to me, 99.9% efficiency, spiral center tube, silicone valve.

 

Yes, I also found this at Walmart a couple of weeks ago. Limit of two jugs per household address, not sure whether the promotion is continuing into September.