New filter - high restriction?

[Mark Rinker]

Running OEM paper filters in both the Dmax'es. Yesterday I notice that truck #5s restriction meter is nearly to the red. Check mileage and its got < than 5K on the filter. Filter is fine. Truck is stock LB7. Other truck is LLY, never seen the restriction gauge even move between air filter replacements.

Bad gauges? I was thinking about switching the two and see what happens...

[Onebigcanuck]

If you have the new one that was n/c from GM. it does filter down to a smaller microns than the previous one. I would think that would restrict the fuel flow somewhat.

[dieseldummy]

Has the air box been modded? Before I modded mine as per JK's instructions it would suck the filter minder in stock. Now it doesn't budge a bit even with the VA on.

[Kennedy]

Yep, if you have the ducts into the inner fender it will do this. Especially if you have a power adder being used.

[killerbee]

This will probably be John's worst dream seeing me post here. Sorry, I just need another home for my forum fix for awhile.

I just thought I would ask: is it possible you have the wrong paper element? There are 2 that look almost identical, but one has about 30% fewer pleats (gasser) and surface area.

edit: muffed up my first post by asking the mod a stupid question. Uggg.

[Mark Rinker]

Hey Killerbee...(one of my favorite vintage SNL skits with Belushi)

It could bee! Local Goodyear dealer did the service this time. I'll have to compare that element to the OEM GM element.

[killerbee]

I did notice, an obvious thing that sets them apart, is the d-max element has several glue strips across it, presumably to keep the pleats from collapsing, and for rigidity, under high air loads.

If you have the glue strips, you have the right part. Absent the glue strips, it could be possible what happens is that the pleats lay over on themselves, as the d-max pulls 2-3x the air of the gas element. .

I looked at what I had in the garage, and I have actually come up with 3 delco elements that will fit the housing.

a1519c has fewest pleats
a1518c has more pleats, but no glue strip
a1618c is what you need, has the glue.

[jbplock]

I did notice, an obvious thing that sets them apart, is the d-max element has several glue strips across it, presumably to keep the pleats from collapsing, and for rigidity, under high air loads. ... a1618c is what you need, has the glue.

Killerbee,

Good point! .. When first looking for a source to buy AC filters online I found a vendor that was selling "AC Duramax Air Filters" at very low price .. A closer look revealed that they were the A1518C.. I sent them an email informing them that it was the wrong part but they didn't change their ad .. buyer beware...

Here’s a Motor Age article on the subject ... Duramax diesel engine air filter (http://www.findarticles.com/p/articles/mi_m3102/is_8_124/ai_n15402640)

:)

[Pewter Max]

On my 01 I used to have that problem with the factory Phone Book , every time I pulled my 5er I would notice that the "Suckometer" would be in the yellow - I changed to an Amsoil filter and I haven't had that problem since .
If you notice - the gauge is downwind from the filter so I don't think the number of holes in the box has any thing to do with it getting sucked in . Here's my $.02

83000 miles and still going Strong !!

[Kennedy]

I'd suggest the Uni foam element and the air box mods on my Tech Tips.

Are you running LPG on the 01?

Are you still ducted into the inner fender?

[Mark Rinker]

Not quite yet on the LPG, JK. The intake is bone stock '01 LB7 variety, including fender air.

The digital boost/pyro gauge and LPG install will be completed next week with a little luck. Will check the filter when I stop by the shop Monday to see if its the correct filter.

Once I have established a stock baseline of boost levels and EGTs with the new digital guages, I'll be testing out-of-the-box MSD settings and effects on boost and EGTs. A few weeks of pulling in 'stock MSD' trim will follow, with lots of data being captured.

One of the obvious mods this truck will need is boost increased in proportion to additional fuel and a free flowing filter element. I'll likely be following your recommendation, JK.

[SoTxPollock]

killerbee is correct, it has to have the glue strips that act as stiffeners to keep the pleats from collapsing under high air load. I noticed my gauge moving toward the center, so I pulled the filter and it was full of bugs etc. vacuumed it out with a shop vac from the dirty side put it back in and the gauge didn't move after that. You may not have much dirt in 5K miles, but other critters can plug it up real fast.

[Mark Rinker]

I had a filter FULL of bees last summer. Not sure if it was from one swarm, or a sunny drive past lots of alfalfa fields, but there were 30+ honeybees dead and stuck in the pleats...

[SoTxPollock]

Right after I got my truck, wife and I were headed for a church picknic in a town about 40 miles away. I'm out enjoying the morning, almost no traffic and all of a sudden I couldn't see through the windshield. I thought some oil fitting or hose had popped loose and covered my windshield with oil. I pulled over and behold bees everywhere. The front hood and grill were packed. Got out paper towel and wiped off a spot big enough to see through and proceded to the nearest car wash and yes the air filter has some there too. At least I know I'm not the only one. If they were killer bees I probably slowed down the migration north for a few months. There were just thousands of them.
Final comment on filtration. If your going with the serious power adders it needs all the air it can get, I'd listen to Kennedy. I don't know of anyone who has dynoed more torque and horsepower than he.