According to my diesel mechanic, the low sulfur diesel is bad for the gaskets (or something with the engine). And too fix the sulfur issue, the additives will improve that issue. Haven't done any research on it myself.
The additives do boost my daily driving by 1mpg and 1.5 on the interstae. I can use one jug on about 4 tanks of fuel. So lets do the numbers, My base mpg w/out any additive is 14.5mpg for a 30 gal tank=435miles till my next fill-up. Now w/additives, 15.5mpg for a 30gal tank=465miles till next fill-up. Then keep in consideration that that jug lasts 4 tanks. Thats an extra 120 miles with additive. So say 120miles (I wouldnt have gotten by not adding additives)/14.5mpg=8.28 extra gallons the additives gave me. Then 8.28gal x 2.89 per gallon=$23.92. I couldn't find walmart or anyone else's price for an 80 oz jug on google shopping search, but some of the online stores had it from $13-$15.
So the stuff pays for itself and gives you a better running engine.
Now for the numbers on the Fich fuel catalyst....
Supposedly these unit lasts 250,000
So with my 14.5mpg, thats 17,241.379 (2.89 per gal x 17,241.37=$49,826.49) gallons of diesel throught that 250,000.
If the fitch fuel catalyst bumped it to 15mpg, that will be 16,666.666 gallons of diesel through out the 250,000. That's 574.713 less gallons (574.713x2.89=$1660.92)
And if it just does 1.5mpg increase...thats 1,616.379 less gallons (1,616.37x2.89=$4,671.30...For a $450 product.
Just seen your post BIG JOE. Is there anyway to tell if this would dry out the gaskets an o-rings? Too many "probablies" and "mights" have been posted.