Any advantage to small filter?

[farrarfan1]

I know the AC DElco PF47 and PF52 is interchangeable since I've owned 3 Luminas, 2 Blazers and I maintain my Mom's Buick Century. I accidentally discovered this several years ago by accident when I was changing the oil in my 96 Blazer(PF52) and 95 Lumina (PF47) at the same time and noticed they where same diameter.My 05 Uplander calls for the PF47 but there is plenty of room for the longer PF52, which was also the case on the other cars. I know the advantage to the larger one is that it allows slightly more oil to be in the engine and possibly more filter media.I know it's an excercise in futility to try to figure out why GM uses the smaller one when the larger one fits but there has to be a reason.There are numerous other applications for other makes that allow a larger filter than OEM recomends besides GM. Is there any advantage to using the smaller filter? As usual thanks in advance.

 

[Gary Allan]

For all we know it's a function of the manufacturing assembly process. Ford uses the lamest fittings on their oil cooler lines in the modular engines. It's simply because the assemblyline worker has to screw in one bolt in the process. Maybe the assembly process requires this clearance at that time, but not after the engine is installed. I doubt the reason is the few fractional pennies that one filter may cost over another in the production of the filter ...but who knows??

 

[Hootbro]

If GM can get by with a cheaper and smaller filter, they will. I remeber reading a few years ago about how GM saved 5-8 million dollars per year by not painting the metal ash trays they installed in cars at that time in the 1970's and 1980's. So a few pennies saved on each car can add up over time.

Hootbro

 

[labman]

I see no reason to slam GM for for what is a common practice elsewhere too. I think it is a combination of the space issue and minimal requirements for oil filters. Besides, many of the smaller filters pack the media in much tighter and may be using a higher quality media. Does anybody have any real proof a PF 52 is better than a PF 47? Or more expensive to manufacture? Filter guy??

There was plenty of room for the PF 52 I substituted for the PF 47 on the Quad 4 in my Grand Am. However, not all the Quad 4 applications may have had room. It would be easier to specify the PF 47 for all of them, than to figure out where it could, and could not be used.

quote:

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Originally posted by Hootbro:
If GM can get by with a cheaper and smaller filter, they will. I remeber reading a few years ago about how GM saved 5-8 million dollars per year by not painting the metal ash trays they installed in cars at that time in the 1970's and 1980's. So a few pennies saved on each car can add up over time.

Hootbro

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[farrarfan1]

Thanks labman, that's kinda the same thinking I had. I don't know if cost is an issue because on the retail level the 52 and 47 cost the same as does the Fram and Purolator versions.Don't know if that is the same for manufacturers cost at the assembly line.You probably phrased it better than I did by asking does the PF52 provide any real advantage over the smaller one.I guess it's really not that big of an issue since they are both readily available.

 

[Hootbro]

quote:

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Originally posted by farrarfan1:
Thanks labman, that's kinda the same thinking I had. I don't know if cost is an issue because on the retail level the 52 and 47 cost the same as does the Fram and Purolator versions.......

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Anything that takes more material to make will cost more. Might not be passed on to the consumer but the manufactuer will be paying more for the material. When I go to wall mart and look at a ST6607 filter that is real small and a ST8 (FL1A) that is quite larger for the same price, it is not rocket science that Walmart has Champ averaging the price across a broad spectrum of filters with most going for $2.07. Only the very large Diesel filters and the Ecotec cartridge filters are priced higher I am sure due to cost that can not be spread out amongst the other sizes.

Hootbro

 

[Gary Allan]

This is where Mel could shed some light. I tend to think that the cost of a filter is mainly in the process and not in the material ... within certain limits. I think that the cost/fatigue time on the machinery ..the electricity to run the line, the personnel to man the line makes the $50 more in sheet metal and media per 50,000 unit run a non-factor. That is, the fixed costs are so far ahead of the variable costs that it isn't worth mentioning. I naturally could be FOS in this opinion. I would think any real economy would be in the terms of "one (smaller) size fits all".

 

[Larry the Cable Guy]

quote:

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Originally posted by Gary Allan:
I tend to think that the cost of a filter is mainly in the process and not in the material ... within certain limits. I think that the cost/fatigue time on the machinery ..the electricity to run the line, the personnel to man the line makes the $50 more in sheet metal and media per 50,000 unit run a non-factor. That is, the fixed costs are so far ahead of the variable costs that it isn't worth mentioning. I naturally could be FOS in this opinion. I would think any real economy would be in the terms of "one (smaller) size fits all".

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Gary - I agree with your thoughts on this. Heck, it could even be that "one LARGER size fits all" makes economic sense at the manufacturing level.

Steve

 

[T-Keith]

The larger filter is usually recomended when the have space, both will work fine and the difference in media probably changes more between brands then sizes. In some applications I would not use the longer filter, like 3800s in W-bodies and older H-bodies.

-T

 

[labman]

Good point on different brands. I have read posts where somebody was going to use a big empty orange can in place of a quality OEM filter. Still, I figure the PF 47 could be using a more expensive media, and actually cost more to manufacture. How fast does a pleating machine run? Do more pleats take longer to make?

At retail, the one price fits all, likely maintains sanity and customers upset about a filter behind the wrong price. When my Grand Am was new, I think the number was 1227 instead of 47, and I had to argue with the cashier at K-mart that it was on sale for $2 too. Been easier then if I knew I could just buy a PF 52. Later AC changed their part numbers, and PF 47 was easier to find, but our K-Mart closed, and nobody stocked the PF 1177 that replaced the PF 9 for my truck.