I can't help but jump in here on the topic of oil & oil filter quality. There is a lot of misconception expressed here.
The two big factors in the quality of oil is the base stock and the additive package. Base stocks are labeled according to their nature.
Group I is petroleum that has only undergone fractional distillation to end up with molecule size of a certain range so the oil has the right viscosity (thickness). Very little of this is used today to make motor oil.
Group II has had additional processing to remove more impurities and perhaps some larger molecules cracked down to smaller sizes. It tends to be more uniform than Group I. There is also Group II+ that goes through a hydrowash process to gain still more uniformity and remove impurities. Group II+ is water clear and is sometimes called "pure base" or even "isosyn base". It was developed by Chevron and used by Pennzoil and others. Much of today's engine oil base stocks are mostly Group II or Group II+.
Group III continues the same general process as Group II+, but to a much higher level. Most of today's "synthetic" oils are Group III based. As to if it really is synthetic or not depends on how you define "synthetic". There was a disagreement between Mobil and Castrol as to is Group III really was synthetic or not. It was settled by some sort of petroleum advertising committee. In the US, Group III can be called synthetic. In much of the reast of the world it cannot.
Group IV is a specific chemical that is made synthetically. I can never get the name straight, but it is either PAO or POA.
Group V is a sort of left over category. If it is synthetic and not Group IV, it is Group V. These are usually Esters.
Mobil 1 is mostly Group IV.
Red Line is mostly Group V.
Most of Amsoil's product line is Group IV although at least one of them is Group III.
Most of Valvoline Synthetic is Group III.
Castrol Syntec is Group III.
Castrol Edge is mostly Group IV (interesting, since Castrol claims their Syntec is better than Mobil 1).
Pennzoil Synthetic is Group III although when Pennzoil Platinum was first introduced it was a new molecule that was very nearly the same as Group IV, but since it wasn't Group IV is was actually categorized as Group V. It was only out a few months before it was switched to Group III. Prior Pennzoil Synthetic was Group IV.
Wal Mart's house brand synthetic is Group III.
Enough of the base stocks.
The additive package needs to be tailored to each oil depending on the base stock. The additive package adds detergents, dispersant, pour point depressants, viscosity index improvers and more, depending on the needs.
Depending on where the base stock came from, the collection of molecules that make it up are a bit different. Their ability to dissolve solids (such as carbon) and their ability to mix as well as how well they pour at cold temperatures and even how much they thin out as they get hot varies considerably. The additive package tries to compensate for all that as much as possible. With the right additive package, even Group I base stocks can perform as well as an average Group II.
All the individual groups have their own advantages and disadvantages. Overall, the one with the greatest temperature range is Group IV. It will handle extreme heat or cold better than any of the others.
Group III is much cheaper to produce, and with the right additive package it will perform nearly (but not quite) as well as Group IV.
Back to the non-synthetics. Most are Group II or Group II+. Today's conventional oils well perform very nearly as well as today's synthetic oils. Over the last few decades, the gap in performance between synthetic and non-synthetic has narrowed greatly. They are driven to it by the American Petroleum Institute's (API) ever tightening specifications. The current one is API SM. They will not handle the extreme temperatures as well and they will not hold up in use as long. Changed at the right frequency and away from extreme temperatures, they will keep and engine just as clean and prevent just as much wear as synthetic. Today's oils will easily go 5,000 miles between oil changes and properly maintained engines will run easily past 200,000 miles.
So in summary, today's non-synthetics and synthetics greatly exceed the need. It doesn't really matter which one is best, they all exceed the need.
In my opinion, Mobil 1 is the best, but I buy what is on sale.
Now on to filters. Fram is very poorly made. Take one apart and compare it to any other filter on the market and you will probably never use one again. However, it probably marginally meets the need at least most of the time.
Some of the more expensive Frams are reasonably good filters, but I still avoid them.
The other big filter maker in the US at this time is Purolator. Beside their own brands, they make filters for Bosch and Motorcraft and probably others. The standard Purolator is much better made than Fram. Purolator also makes the Pure One, which is an exceptional filter and a great value. Most Bosch filters are nearly the same as Pur One filters. Although Motorcraft filters are made by Purolator, they are different than those with the Purolator label. Motorcraft tends to use better filter media. They are probably close to but not quite as good as a Pure One.
Champion Laboratories makes filters for many other labels, including STP. I don't very often see it under their own name. Their run of the mill filter is similar to Purolator. I don't like them quite as well, but they are still head and shoulders above the standard Fram. Champion also makes premium filters for Mobil (Mobil 1), K&N, and Castrol (Castrol Edge). These are all excellent filters, but I agree with others that have said that they at $6.00 filters in $12.00 boxes. They are not that much different from Pure One or Bosch.
I hope this helps.
