Oil filters are getting tiny
 

I was looking at a couple of late model cars the other day, a new MINI and an Audi A3 were a couple, and noticed that, while looking under the hood, the oil filters are tiny! As in the size of a can of tomato paste. Is this all in the name of weight savings and cost? I can't imagine filter technology has leaped forward any great amount in recent years.

Even on a late model BMW 128i, the 3.0 liter engine (bigger than my 2.5 liter 325i) has a shrunken oil filter. Bigger engine, smaller filter.

I was changing the oil in my wife's saabaru and the new oil filter I got was smaller than the one I removed. The numbers were correct, it was just a little smaller. There isn't a space constraint, so it seems a larger filter would be more effective.

Early Miata has a tiny oil filter, but just about everything on an early Miata is tiny.

Maybe Mazda was a trend setter back in 1990.

It seems that oil filters are going the way of pre-packaged food or household goods, the package keeps getting smaller, but the price remains the same or goes up. My oil filter on my Diesel 7.3 L Ford, is honestly a foot long, and about 5-6" thick. You need to pour two quarts of oil into it before installing, and it is always a mess to replace (oil running down wrist).

I'm sure that it is a weight issue for the automaker, because every ounce they can save off the final weight means better fuel economy, and probably a slight bit cheaper.
This is why most new suspesion components no longer have steel inner or outer tubes,while many have gone to composite (melted plastic molded beads) torque rods, and motor mounts.

I'm no conspiracy theorist...

But, as the pieces of the puzzle fall in place, a picture begins to emerge...

-Manufacturers are starting to pipe up that they don't want gear-heads tinkering
-It seems almost every car on the road needs a timing chain at 100k
-Oil change intervals are dramatically longer
-Cars are running much hotter (MIL's 535 runs at 260 with 15k oil chg int)
-Silly things like oil filters are being minimized

I believe, something like a baby-sized oil filter, is just a small indication that auto manufacturers are purposefully building cars to not last, with shorter projected life spans, and high maintenance costs...the new car sale income stream is not profit heavy.

Odd. Just replaced the filter on my e350 v10 (6.8l?), and the filter was really small too... Must be a new trend...

I don't see this as conspiracy theory. It makes good business sense for the auto makers.

If the filter can flow more than enough to keep up with the oil pump along with viscosity changes, why go larger?

When was the last time you had the impression that your filter was really clogged with material when you changed it?

Even on my Jeep's old 4.0 I've gotten into the habit of changing the filter every other oil change because the destructive analysis of the filters over the 15 yrs I've owned it has indicated that there isn't much material at all at the normal oil change intervals.

Snythetic oils last longer, therefore they manage wear in the engine better. This decreases material in the oil. Less material beign filtered out, the less surface area of filter needed to maintain flow.

on toyota cars, i kinda think the oil filter gasket diameter and the thread pattern are all the same throughout their vehicles. so, i you have lots of room you can go up in size. i run a XXXXXXXDX..i dont know the numbers, but i do look for the "D" which is a larger filter. i remember my truck needed a different letter which is a smaller unit.

my wife's suburu filter is tiny.

Yeah, but you can put the filter from a Mazda Millenia on it instead, and it is about twice the size. There have been people that report better oil pressure with the larger filter.

My sentiments exactly. They charge the same, for a lower cost to manufacture item = more profit

A smaller filter, despite my lack of exact knowledge, likely filters less efficiently than a larger capacity one. Increasing internal engine wear faster...again, higher profits for more regular repairs.

If you can't see the point I'm making...idk.

Not being a MechE I'm just using some knowledge I gained through osmosis, but I think you've got the gist of it. I'll take a shot at it...

Filter efficacy is a balance of element surface area, particle size, and flow rate. The greater the surface area of the filter element, the smaller the particle size you can filter out at the same fluid flow rate. Getting more surface area either requires a larger filter body to fit more material or more convolutions in the element, meaning a thinner/stronger element material.

I haven't heard of any staggering breakthroughs in filter element material lately (but then again I'm nobody). Still, it's a fair bet they're letting larger particles through to maintain the same flow rate through the smaller filter. More particles = shortened engine life.

Maybe we need Lubey to chime in. :)

Don't really agree with all of this statement. The element material itself controls the size of the particle allowed to pass, not the surface area of the element. increasing flow rate is not going to give you better particulate isolation IMO. I do agree with the surface area affects on flow rate and the restriction due to the size of the filter..

To comment on Toby's post, I'd expect the introduction of a larger volume filter for the same overall oil capacity would result in lower oil pressure unless the spec filter was to restrictive in the first place.

Right. In order to maintain the same flow rate with a different element that provides a smaller particle size pass-through, you need to increase the surface area of the element.

I thought that's what I said, but sorry if I wasn't clear.

Toyota moved to smaller filters starting way back with the 22R engines (possibly RE). They followed suit with the 1FZ engines also. Both of those families still last forever. I don't think it is a conspiracy - I think it's better engine design. Look at weights, change intervals, all kinds of stuff - what was "cutting edge" back in the '70s is chuckled at now...

Oh yeah, wholeheartedly agree with this..SmileWavy

You've nailed what can be the danger in the idea that just going with a larger filter is going to be mo betta. Sacrificing filtration for flow is bad juju.

To the Toyota point above, my Sequoia 4.7 has a surprisingly small filter. But it does a very good job. I change dino Valvoline every 10k and oil analysis comes back with excellent filter performance. I only run quality filters like Purolator and Motorcraft.

You guys are a pile of old curmudgeons. There is no big conspiracy here - just optimization. The engines are running a LOT cleaner than what they used to. A lot less crap fills the filter. You cannot compare the requirements for a diesel truck filter from a 7.3 V8 with a filter on a modern gasoline engine.

I really like what has happened in automotive engineering. It finally isn't moving at snails pace. Back in the day the cars stayed the same with different sheet metal. VW for example. How long did they make the bug? 30+ years with the same tech. Even the hot cars. Corvette? Early 1960s C2=C3 all the way to the 80s. The biggest innovation you got was H.E.I. and then finally FI ...

G

Modern engines don't dirty up filters unless the engine is damaged and eating itself up, and by then a filter won't help.

And cars went from $3000 to $40,000 .......