You can sure add a lot to yor fuel bill by additives.........depending on your driving habits, this may be significant or minor (miles driven). In my case I have just topped the 350,000 mark (01 Dodge) and use additives on a rare occassion.....like maybe 5-10% of the time - and then only if I suspect the fuel may be suspect - very small local out of the way place that doesn' look like they sell much diesel - and I have to have fuel. This has occurred when travelling south of the border - or way north - I mean Way North...... Otherwise - I think a waste......
01 Dodge 4x4 CC - Twins - EDM 4.0 injectors - AFE Megacannon-Magnaflow-FASS-CAM-Ported-ATS Manifold-Head Studs-Triple Disc-full gauges - Edge Drag Comp - No DRUGS or Water - Bombed - 557 HP, 1135 ft lb latest dyno (Jan 05)