2nd fuel filter on Dmax

Roofer · January 22, 2004

What do you Dmax guys think about the systems for 2 micron filters along with the stock fuel filter? I really think that if the stock system is good enough for GM to warranty it, it is good enough for me. Why should we have to spend an extra $200 or so for something it should already have, if in fact it NEEDS it? What do you think?

clk7711 · January 22, 2004

I think its a good idea. Other manufactures like Cat, Cummins, John Deere all have secondary filtration. With the new Bosch fuel systems on the Dmax and new Cummins, fuel pressures can reach 23,000 psi. If I had a duramax I would strongly consider additional filtration, if I was planning to keep it after warranty. I'd hate to see the bill to replace all 8 injectors on a Dmax when the warranty runs out.

Here are some interesting facts I read in a Stanadyne brochure.

The naked eye cannot see particles smaller than 40 microns.
A grain of sand is approximately 100 microns.
A human hair is approximately 70 microns.
A single grain of talcum powder is 10 microns.

Secondary filtration is done at the 2 micron level.

At those high pressures, it wouldn't take much to destory an injector.

JayMan · January 22, 2004

I have Racor filters on the bulk tanks and Racor's on the commercial equipment. When you change the element, what you see caught in the pleats will scare the bejeezus out of you.

Yeah, love to ruin a bunch of $$$ Cummins injectors.

Not sure where you'd find the room to mount a Racor or other filter on the Duramax.

Roofer · January 23, 2004

Racor makes the filter that the Dmax uses. I read that Racor is developing a 2nd filter system. There are a few others on the market as well.

Thanks for the comparisons clk7711.

Supposedly the Racor stock filter is 4 micron, but been tested only to reach the 10 micron level.

Jay P · January 23, 2004

I have one on mine from Kennedy Diesel. Not to hard to put on. I put it before the factory filter so the dealer can't claim I let junk get to the injectors from adding the filter.

Jay

4x4man · January 23, 2004

I added a CAT pre oem fuel filter on my truck, bought as a kit from nicktane.com. To me $200 is a lot better than $4-6 grand after warranty. I have had mine on for about 6,000 miles and no problems. I gained a good 2mpg on my trip to Vegas over the holidays with the cat filter, then the same trip just 6 months prior without. I think it was worth it!

Bob

LARSONEM · January 23, 2004

Check out this website below. There is a ton of information and discussion under Duramax Diesel Engines regarding additional filtration.

The Diesel Place

JayMan · January 24, 2004

On my commercial equipment and the bulk tanks, I've had the best luck with two stage filteration: the first stage takes out the water and gunk to about 20micron, the second stage down to about 4 micron.

The first stage has a clear bowl and the Racor does a good job of getting most of the water and the larger solids out of suspension before it hits the element pleats.

BlackSilver · January 24, 2004

I added a CAT pre oem fuel filter on my truck, bought as a kit from nicktane.com. ..... I gained a good 2mpg on my trip to Vegas over the holidays with the cat filter, then the same trip just 6 months prior without. I think it was worth it!

Awwwww, c'mon!

An additional fuel filter raised your MPG? Do you realize how silly that makes you sound!

crashdummy · January 28, 2004

Can't say that it has improved mileage, but I also installed a Nicktane pre OM fuel filter on my new truck. Quality kit and relatively easy installation. If it helps the injector longevity, it is well worth it.

4x4man · January 29, 2004

I added a CAT pre oem fuel filter on my truck, bought as a kit from nicktane.com. ..... I gained a good 2mpg on my trip to Vegas over the holidays with the cat filter, then the same trip just 6 months prior without. I think it was worth it!

Awwwww, c'mon!

An additional fuel filter raised your MPG? Do you realize how silly that makes you sound!

Yes, I am saying the 2 micron fuel filter increased my highway mileage 2mpg ON THAT TRIP. I fueled up at the same stations as I did on the previous trip. I haven't changed anything on the truck since that trip except for the filter, what other reason could it have been?? I don't see how that makes me sound silly when numerous other people have found similar results. But maybe then we are liars

If you really care, do some research and read all of the findings. It has been found that most people who have added secondary filtration to their dmax's have received smoother and quieter running engines as well as a mpg boost. Don't believe me, I don't care. This isn't snake oil or an addition of a tornado or something....

Bob