Originally Posted by armyrgr
SpynTec Hubs? Explain brother. And yes we do. - SFC Eddie 6th RTB Florida Phase instructor last 3 years. Headed to Alaska in Aug for my PSG time.
The modern solid axle and IFS trucks come with unit bearings. While not bad, they are strong and require no service, they force the front wheels to turn the axle shafts, ring/pinion/ and front driveshaft even when in 2 wheel drive. Several manufacturers (my choice was spyntec) make old school hub conversion to allow you to disconnect the front hubs therefor only spinning the wheel/tire, not the whole front end.
The water/meth is a bit of a jump of the gun. Most tuners will require 93 octane for the greatest gains. Here in Cali 93 octane is rare. Running the Water/meth will allow me to run the 93 octane tune while still using 89 octane fuel. Plus the computer will begin to sense the extra fuel over a few cycles and cut back on the injector pulse using less fuel. Hence better MPG.
Keep in mind, none of these mods are cheap (Hubs $1700, Water/Meth $600, Tuner $450), but if you plan to keep your truck for a long time, or plan to lift it (larger wheels and tires) they help you maintain your fuel economy.
Example is I am running 35" Cooper STTs and am getting 12.5mpg mixed daily and 15-17mpg freeway (weather/traffic dependent).
If you look close you can see that my hubs can be locked or set to free