Guys, let's keep the focus on the help a member needs... . heck, even I still ask repetitive questions from time to time myself...
To be strictly accurate and fair, Gary is correct, we should make as much use of the search function(s) as possible but it does happen from time to time that you need to know the correct question (search criteria) to ask too...
OH... and inviting another member to meet half way on state border is a full 10 RWHP penalty...
,,,,not to mention the 10 male hairies that goes with it... not to mention a contravention of the site guidelines, and the chapter of "bomb thy neighbours truck" in Our Lady Of Acceleration's bible...
Besides, Gary is just uncommonly blunt, I'm sure No insult was intended.
MOverton, don't be shy in here... we're all pretty well nuts to start with... now, additives...
Some good one's have been mentioned but maybe you should be asking something a little more to the point... . in an indirect way... .
What should an additive do for my application/needs???
Well, our pumps are lubricated AND cooled SOLELY by fuel... . no oil, no other sources of lube or cooling are used, or rather, available.
(In no particular order, are my thoughts on additives ..... )
This means that under normal conditions our pumps need lubrication, in my opinion, beyond the lube properties of the fuel itself.
So, "lubricity" is a necessary feature to any additive we use.
Next, depending on climate you'll need some control over fuel gelling or thickening... so you want some "anti-gel" ability as needed.
The next item is detergent properties... . remember this WILL NOT make up for a dirty fuel filter or poor service intervals and bad fuel. The detergent will help keep your entire injection system clean, or at least cleaner.....
Since injection systems will, over time, begin to actually wear out due to high pressure fuel passing through them all the time you don't need deposits making things worse, or you'll end up with bad mileage, low power, lots of smoke and poor engine performance just to name a few things.
The next item is cetane rating(s). In our case cetane is the diesel version of octane (for gas).
If you are very very lucky you'll have fuel that is a true "premium" fuel. This is one of th lengthy topics that Gary may have been referring to. There is a difference between advertising premium and "TRUE" premium which I won't go into here.
Basically the higher the cetane rating of the fuel the better the entire system/truck will perform and run. Now, the cetane ratings on fuel can vary a huge amount from North to South, and East to West.
It's not uncommon to find cetane ratings of 42, 45, 46/7 ... . some as low as 40. This is made worse in winter when we get "winterized" fuel. It is really poor quality as reflected in idle speed/quality/smoke/mileage/general performance... .
Here are my recorded stats... . on winter fuel my mileage drops by approx. 1. 5 - 2. 25mpg, my idle drops about 75 - 80RPM and the idle quality is noticably poorer, I have more exhaust smoke as well.
All of this can be helped to one degree or another by using a cetane improver. Some will claim the cetane improvement will be (for example) between 5 - 8 points. Other's will claim 8 - 10 points and so forth.
There are other properties you will make use of in additives but those are the highlights... .
I have found that Stanadyne PF makes a noticable difference in my truck, particularly in winter like now. I loose idle speed due to fuel grade but gain most or all of it back with the use of cetane improvers like Stanadyne. They have other products that do other jobs or mulitiple roles as well (as noted above)
Howes I find is really more aimed at lubricity and detergent action... at least that's been my opinion when comparing it's use to Stanadyne PF. (I can get Howes for free and choose not to use it unless I'm stuck with no additive at all.
The other guys have mentioned other company additives for you to check out. Pick one and try it for a couple full tanks of fuel. Usually I suggest to a "first timer" to double up the dosage on the "normal" instructions then go to "as directed" on the second tank.
You should find some differences in idle, smoke, startup, power, etc... . pay close attention cause it can be subtle at times... .
Well, my meds have worn off and I'm going to stop now.....
pastor bob.....
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