Air Filters Replaced Too Frequently.

[George7941]

I installed a filter restriction gauge when I bought my Sierra truck, and, at 25k mi on the air filter element, the gauge still indicates no restriction. I will probably go 50k mi before I replace the air filter element . I trust the gauge and, if it says 'no restriction' then I see no need to replace the filter element. I tested the restriction gauge by applying 5in water column vacuum to it and the gauge registered 5in wc.

On MD trucks at work, I only replace the air filter elements when the restriction gauges indicate restriction and the trucks go 100k to 150k mi before needing a new filter element.

The gauge I used on the Sierra is Fram SP3539.

You will save money by avoiding needless filter replacements if you intall a restriction gauge. Also, everytime you remove the filter element, there is a risk of dirt falling in. The service manuals for the MD truck engines advise against opening the air filter box unless indicated so by the gauge.

I live in a big city. If I lived in the Canadian countryside I could probably go 75k mi on air filters because of cleaner air away from a big city.

 

[Billy_D]

I would change the air filter at the 30K mark. With all the salt they use during the winter to clear the roads, you should be changing it every year. Just my

 

[sciphi]

Neat! An air filter life monitor!

 

[George7941]

They use a lot of salt in Toronto and my present filter element has been on my truck for almost three years. I trust the Wix filter element to filter out the salt dust in the winter. Needless to say, use only high quality filter elements.

 

[RF Overlord]

Exactly how much restriction is "too" much? It would seem that for maximum efficiency, the AF should be replaced just before it becomes "too restrictive". Having said that, I like this idea and I'm seriously considering doing it on my daily driver, but I'd like to know whether the gauge has a "warning" area, like it goes yellow before going red, so I would know that the time to replace the filter is fast approaching.

Is there a one-size-fits-all standard for restriction? You mentioned the level of 5" wc...is that a common threshold, so if I replaced my AF at 4" I'd be good?...something like that?

 

[Bill in Utah]

Originally Posted By: sciphi
Neat! An air filter life monitor!


My 2000 Silverado (and Moms 2002) has them standard. My 2004 GMC does not.

I've got to get one installed. They are handy.

Any suggestions where to get one?

I agree that people are changing WAY too often. (sorta like oil!)

Thanks, Bill

PS: Looking around, looks like price for the Fram is around $30 and NAPA seems to be from $21 to $60. Close?

 

[Colt45ws]

I got mine from Ryder fleet supply. Mine goes up to 20". Probably too much. It has not even clicked for 6" yet though, with 14k on the filter.

 

[George7941]

Originally Posted By: RF Overlord
Exactly how much restriction is "too" much?


Diesel engine manufacturers recommend replacement at 20 to 25 in wc, depending on the manufacturer. For example, on a 1999 Cummins B engine, used on Dodge pickups, Cummins recommends replacement at 25in wc. On gasoline engines, max rcommended restriction is 15in wc.

I always err on the conservative side (engine oil change interval on my Sierra is 4 to 5k mi on dino and the OLM usually comes on at about 6k mi). On diesels, I change at 12 to 15in wc and on gasoline engines I change around 8in wc. I will be past 50k mi before the gauge registers 8in.

I bought my Fram gauge about ten years ago and I paid around forty dollars Cdn for it then. Things tend to be about 30% more expensive in Canada, so the 30$ sounds about right. The Fram unit is of good quality, it is still working well after ten years. You won't go wrong buying it.

These gauges are marked in inches of water column, in 5in increments. The flag moves continously between these markings, so you can extrapolate to get 8 in.

Air filter elements become more efficient (provides cleaner air) when they are somewhat loaded up. An element offering 5in restriction traps more particles than a new element because the pores have become slightly more restricted.

Atmospheric pressure is around 360in wc, so a 5in restriction is around 1.4% restriction. On a carbureted engine the mixture will richen a small amount from that restriction, but with fuel injected engines monitoring manifold pressure and mass air flow, I don't think this 1.4% restriction would have any effect at all on fuel in a fuel injected engine.

 

[Gary Allan]

These are available as NAPA/WIX numbers.

Wix - Part Nos: 24800, 24801, 24802, 24804

I'm not sure why, but they offer one of them as a kit with 10' of hose for remote viewing. I guess if a filter was buried somewhere it makes sense. I'd probably not look forward to servicing it if it required the kit.

One PSI is equal to 27.7 inches of water column

 

[wander2039]

Would be nice if the gauges was cheaper. 24800 looks like $55 and 24804 looks like $60 at OReilly's. Filters average 9 bucks don't know probably take 500k just to equal out. But then again doesn't filters "filter" better the longer their used?

 

[bustednutz]

Do you check the gauge with the engine running? Therefore you can see the actual air movement at engine speed.

 

[1 SX]

WE are going on 68K miles, (6 years) on the OEM air filter from honda.... I just took it out, hit it a couple of times, and put it back in.

 

[onion]

Good idea. I check these all the time on heavy trucks, but it hadn't really occurred to me to put one on my own vehicle. I'm gonna do that.

 

[mrsilv04]

Originally Posted By: Bill in Utah

My 2000 Silverado (and Moms 2002) has them standard. My 2004 GMC does not.

That's odd Bill... My 2004 Silverado has one.

I have the factory towing package (which I believe includes a HD air cleaner)... could that be why I have one?

 

[Colt45ws]

Originally Posted By: bustednutz
Do you check the gauge with the engine running? Therefore you can see the actual air movement at engine speed.

They ratchet, so they always record the highest restriction and you can check it at any time, on or off.

 

[Gary Allan]

Originally Posted By: Eric Smith
Would be nice if the gauges was cheaper. 24800 looks like $55 and 24804 looks like $60 at OReilly's. Filters average 9 bucks don't know probably take 500k just to equal out. But then again doesn't filters "filter" better the longer their used?


Check with fleetfilter.com Maybe they can cut a better deal

 

[George7941]

Originally Posted By: Gary Allan


I'm not sure why, but they offer one of them as a kit with 10' of hose for remote viewing. I guess if a filter was buried somewhere it makes sense. I'd probably not look forward to servicing it if it required the kit.



The remote kit is for mounting the gauge on the dash. Dash-mounted restriction gauges are an option on HD trucks.

 

[KrisZ]

Air filter gauges are nothing new and have been used in big rigs and heavy industry for a long time. Big fleet owners don't go by fuzzy warm feeling when maintenance in concerned, everything comes to dollars and cents.

I also like the transparent fuel filters that fill up as the load, when the level reaches the mark you change it out, no guess work and you know you're getting maximum performance for your money, No 3 month 3k OCI [censored] or 12 month on air filter.

 

[marvinlee]

Great question: "Exactly how much [air filter] restriction is "too" much?" There is no easy, or even correct, answer. Some factors include: 1) The engine's duty cycle. An engine running at constant RPM and near-full throttle cannot tolerate as much filter restriction as a consumer engine that very seldom operates at full power. An example of the former would be a commercial irrigation pump engine. Most cars would come closer to second example. The operator's preference is another factor. Some of us don't mind losing a percent or so of power at peak throttle, while many would. Much depends on whether one has a giant V8 engine with surplus power, or an underpowered car that needs every bit of its meager horsepower. My view is that car makers should design cars that monitor air filter restriction and integrated it with the vehicle's typical usage experience. Something of the sort is often done with oil change monitors and the air filter offers fewer engineering challenges. Millions of dollars are wasted every year in replacing fully functional filters. It is green to conserve.

 

[Mr_Joe]

Much depends on where you have been driving. Now if your 10 miles back on a dusty gravel road, that may be an issue. If you only get a little dust in a construction zone once in a while, that's 'light duty'. I usually go a little longer than the book may suggest.