What kind do you use and how often?

Stanadyne Performance Formula about every other tank.

I use redline diesel fuel catalyst. Every tank.

Seafoam about every 2 months

Another voter for Stanadyne Performance Formula...been using the stuff for 13 years and no problems and I have 4 diesel vehicles...

Has anyone noticed any mileage improvement with additives?

Be careful with the additives, some of the newer model, designed to run on ultra low sulfur hwy diesel wont like some of the additives.

I tried using Lucas additive in my 2008 Chevy and it put a code for the exhaust filter cleaning. Ran all the diesel out and it stopped. Put some more in and it did the same thing. No more additive for me. I also put a K&N air filter in it and it put it in limp mode. Called K&N and they said some diesels have very sensitive sensors and the oil out of their filter will cause false readings. Took it out and put the chevy one back in and was good to go.

This bulletin is from 2003 I believe. This is how Standyne references it:

GM Approval of Stanadyne Performance Formula�
�Information on Diesel Fuel Additives�, GM Bulletin # 03-06-04-017; March 13, 2003
General Motors has recently issued the above bulletin concerning the use of diesel fuel additives.
In this bulletin, GM recommends both Stanadyne and Racor diesel fuel additives for use in GM
diesel engines to help address the problems associated with water in fuel. The bulletin refers to
two different �technologies� to help remove water: Demulsification (a proven technology used by
Stanadyne and Racor); and Emulsification (adopted by many other brands, often using alcohol).
Both Stanadyne and Racor additives deal with water in fuel by demulsifying, or coalescing it
(making the water form larger droplets), which enable a Fuel Filter/Water Separator to more
effectively remove the water properly. GM is adamant that water should not reach the pump or
injectors in their diesel engines, especially the Duramax engine. Water can cause serious damage
to any diesel fuel system, including rust, excessive wear, microbial contamination etc.
However, IT SHOULD NOT BE INFERRED THAT THE STANADYNE AND RACOR
ADDITIVES ARE THE SAME OR EQUAL - THEY ARE NOT!
Information on the features and benefits of Stanadyne Performance Formula� and Racor
Conditioner Plus can be obtained from literature or various web sites.
Stanadyne Performance Formula� is a multi function, all season product. It is engineered and
designed to deal with any fuel related problems including * Cold weather waxing & pour point *
Cetane * Lubricity * Water (demulsifier & anti-freeze) * Cleaner * Corrosion Inhibitor * Anti-
Oxidant.
Racor Conditioner Plus+ states that it addresses fuel related problems such as, *Cetane *
Lubricity * Water (demulsifier) * Cleaner * Stabilizer * It does not address cold weather problems
or corrosion/oxidization.
For cold weather operation Racor suggests adding Racor Winter Plus+. A Racor user will have to
add and mix both Racor products in order to get benefits approaching Stanadyne Performance
Formula. Even then, the improvement to performance may not be the same, as the Racor product
has less active cetane improver than Stanadyne Performance Formula.
Summary:
Clearly, the most comprehensive, multi-function diesel fuel additive available is Stanadyne
Performance Formula. It is the only additive that addresses virtually any diesel fuel-related
problem with one product, and is the only one that is:
�� Made by a fuel injection equipment manufacturer.
�� Approved by several OEMs.
�� Proven to perform best in independent testing.
For more information, or to request literature, please call Stanadyne Power Products Division,
1 800 842 2496, or visit our website at www.stanadyne.com

I use BG products 244 and Diesel Oil Additive on my truck religiously

i use a can of seafoam every 10,000 miles and a few ounces of 2-cycle pennzoil outboard oil that i also put in my mercury every other tank... seafoam cleans everything up and the oil lubricates the injectors. never had any problems and i recommend this to all the owners of diesels that come through my shop......dont know about dpf stuff, as my 2010 duramax is not fitted with one......do not try oil with dpf in place!

Lucas oil

Howe's when I fill up my 5.9 Cummins. When I change the diesel filter annually, I fill the canister up with Seafoam.

ATF. Half gallon every other fill up.
1.5 mpg improvement since I started doing this.

1992 dodge. Old diesels like ATF.

I use the fuel and oil additive got 567000 miles without a problem. The guys at International Harvester told me to use this stuff years ago.

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